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TRANSPORT & INFRASTRUCTURE

DESIGN

ROXHILL East Midlands Gateway

Strategic Rail Freight Interchange

HIGHWAY IMRPOVEMENTS GEOMETRIC DESIGN STRATEGY RECORD

BWB Consulting Ltd Registered in England 5265863

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TRANSPORT &

INFRASTRUCTURE DESIGN East Midlands Gateway

Strategic Rail Freight Interchange

HIGHWAY IMPROVEMENTS

GEOMETRIC DESIGN STRATEGY RECORD

Birmingham Livery Place, 35 Livery Street, Colmore Business District Birmingham, B3 2PB +44 (0)121 233 3322

Leeds Whitehall Waterfront, 2 Riverside Way Leeds LS1 4EH +44 (0)113 233 8000 London 15 Weller Street

London, SE1 1QU

+44 (0)20 7234 9122 Manchester 4th Floor Carvers Warehouse, 77 Dale Street Manchester, M1 2HG

+44 (0)161 233 4260 Nottingham 5TH Floor, Waterfront House, Station Street Nottingham,NG2 3DQ +44 (0)115 9241100

www.bwbconsulting.com

PROJECT NUMBER: NTH2058 REPORT REFERENCE: NTH2058 DRT

VERSION DATE AUTHOR CHECK APPROVE COMMENTS

1 11.04.2014 S. Hilditch D. Mackrory D. Mackrory Issued with departure applications

2 23.07.2014 S. Hilditch S. Dunhill D. Mackrory Amended to reflect latest scheme design

EAST MIDLANDS GATEWAY STRATEGIC RAIL FREIGHT INTERCHANGE

GEOMETRICAL DESIGN STRATEGY REPORT

NTH209 GDSR REVISION 2

CONTENTS

1.0 INTRODUCTION .................................................................................................. 5

Introduction .......................................................................................................... 5

Overview of the Scheme ......................................................................................... 5

2.0 GEOMETRIC DESIGN STANDARDS ....................................................................... 8

Existing situation ................................................................................................... 8

Standards used ..................................................................................................... 8

3.0 HORIZONTAL DESIGN OF LINKS ....................................................................... 10

A50 EB to M1 SB interchange link .......................................................................... 10

A50EB to M1 J24 interchange link .......................................................................... 13

M1SB to J24 interchange link ................................................................................ 14

Extension to existing M1SB to A50WB interchange link ............................................. 17

Improvements to existing M1 J24 to A50 WB interchange link ................................... 17

Widening of M1 SB between J24A merge and J24 merge .......................................... 19

Improvement to M1 J24 SB merge slip road ............................................................ 21

A453 Northbound (South of J24) ........................................................................... 22

A453 Southbound (South of J24) ........................................................................... 23

A6 Kegworth Bypass ............................................................................................ 24

4.0 SIGHT DISTANCE ON LINKS ............................................................................. 28


A50 EB to M1 J24 interchange link ......................................................................... 28

M1 SB to J24 interchange link ............................................................................... 28

Extension to existing M1 SB to A50 WB interchange link ........................................... 29

Improvements to existing M1 J24 to A50 WB interchange link ................................... 29






5.0 VERTICAL ALIGNMENT OF LINKS ...................................................................... 33


A50EB to M1 J24 interchange link .......................................................................... 34

M1SB to M1 J24 interchange link ........................................................................... 34

Extension to existing M1SB to A50WB interchange link ............................................. 35

Improvements to existing M1 J24 to A50WB interchange link .................................... 35






6.0 CROSS SECTION OF LINKS ............................................................................... 41

A50 EB to M1 SB interchange link (IL2C and IL1A) .................................................. 41

A50 EB to M1 J24 interchange link (IL1C) ............................................................... 42

M1 SB to J24 interchange link (IL1A and IL2C) ........................................................ 42

Extension to existing M1 SB to A50 WB interchange link (IL2A) ................................. 42

Improvements to existing M1 J24 to A50WB interchange link (IL2C) .......................... 43

Widening of M1 SB between J24A merge and J24 merge (D4M for SB) ....................... 44

Improvement to M1 J24 SB merge slip road (MG1A) ................................................ 46

A453 (South of J24) ............................................................................................. 46

A6 Kegworth Bypass (S2) ..................................................................................... 46

7.0 M1 JUNCTION 24 ROUNDABOUT ....................................................................... 48

General Layout .................................................................................................... 48

A50 to A453 NB SLTL ........................................................................................... 49




A453 NB to A50 SLTL ........................................................................................... 50

Abnormal Load Bay .............................................................................................. 52

8.0 A453 DEVELOPMENT ACCESS / A6 KEGWORTH BYPASS JUNCTION .................. 53

9.0 A6 KEGWORTH BYPASS JUNCTIONS AND FEATURES ........................................ 54

Overtaking opportunities ...................................................................................... 54

Ashby Road Junction ............................................................................................ 54

Whatton Road Junction ......................................................................................... 54

Farm access points .............................................................................................. 55

Non-motorised user (NMU) crossing points ............................................................. 55

A6 London Road roundabout ................................................................................. 55

10.0 MOTORWAY SIGNALLING AND SIGNAGE .......................................................... 58

M1 Southbound ................................................................................................... 58

A50 Eastbound .................................................................................................... 63

11.0 SUMMARY OF DEPARTURES .............................................................................. 64

12.0 REFERENCES ..................................................................................................... 69

Figures 3.1 to 3.4 – TD22/06 Merge and Diverge Assessments .................................. 70

Appendix A – Scheme layout drawings ....................................................................... 71

Appendix B – Long section drawings .......................................................................... 72

Appendix C – Cross section drawings ......................................................................... 73




1.0 INTRODUCTION

Introduction

1.1 BWB Consulting have been appointed by Roxhill to undertake the design of the major

improvement to M1 Junctions 24 and 24A (“the Scheme”) that is associated with their

Strategic Rail Freight Interchange (SRFI) known as East Midlands Gateway (EMG). The

location of the scheme is shown on Figure 1.1.

1.2 The M1, A50 and A453 are part of the strategic trunk road network that is maintained

and operated by the Highways Agency (HA) on behalf of the Secretary of State for

Transport.

1.3 The report is based on the following information:

Highways Agency design standards listed in Chapter 2 below

Topographical survey information prepared by Greenhatch

OS mapping, aerial photos and Google Streetview

Various site visit carried out during 2012 to 2014

1.4 The purpose of this report is to confirm the strategy for the geometric design for the new

slip roads. The strategy is prepared in accordance with IAN149/11 “Existing Motorway

Minimum Requirements” paras 1.13-1.16. Although only the M1 is classed as an existing

motorway, the DSR will cover the entire J24 and J24A improvement scheme, A453 site

access junction and the A6 Kegworth Bypass, as it serves to create a useful auditable

record of design decisions that have been made.

1.5 For each aspect of geometric design this report will describe the proposed geometry.

Where relaxations are proposed then a justification will be provided. Where departures

from standard are required, these will be highlighted and cross referenced to the formal

departure applications.

1.6 This report does not include analysis of the local highway works that are to be designed

in accordance with the 6Cs design guide.

Overview of the Scheme

1.7 The purpose of the Scheme is to provide sufficient capacity on the highway network to

facilitate the development of the SRFI. The Scheme will:

Provide a ‘free-flow’ link from the A50 Eastbound to the M1 Southbound through

construction of a new merge onto the M1 at J24A. This has consequential changes to

the M1 J24 SB diverge slip road.

Improve the capacity of the M1 J24 roundabout with removal of the A50EB to M1SB

traffic and construction of segregated left turn lane from the A453NB to A50WB

Further improve the capacity of the M1 J24 roundabout with signalisation of the

A453SB approach.

Remove four existing conflicts on the A50 between J24 and J24A (Church Street

junction, Main Street junction, the Hilton Hotel access and a field access).

Provide a southern bypass for Kegworth.

Provide a new junction on the A453 between J24 and J23A to serve the Kegworth

Bypass and the SRFI development.

1.1 The scheme will involve the construction of and alteration to the following links:

A50 EB to M1 SB interchange link

A50 EB to M1 J24 interchange link




M1 SB to J24 interchange link

Extension to existing M1 SB to A50 WB interchange link

Improvements to existing M1 J24 to A50 WB interchange link

Widening of M1 SB between J24A merge and J24 merge

Improvement to M1 J24 SB merge slip road

A453 Northbound (south of J24)

A453 Southbound (south of J24)

A6 Kegworth Bypass

1.8 Refer to Figure 1 for the site location plan. The drawings contained at Appendix A

show the scheme layouts.




Figure 1.1 Location plan

EMG SRFI SITE

M1 J24 / J24A

IMPROVEMENT

A6 KEGWORTH

BYPASS & SITE

ACCESS




2.0 GEOMETRIC DESIGN STANDARDS

Existing situation

2.1 The M1 north of J24 is a dual 3 lane rural motorway and has a 120kph design speed,

south of J24 (to J23A) it is a dual 4 lane rural motorway and again has a 120kph design

speed.

2.2 The A50 west of J24A is a dual 3 lane all purpose road up to J2 (the A6 Derby Spur), and

has a 120kph design speed.

2.3 Between J24 and J24A the A50 north / west bound is effectively a 2 lane rural all-

purpose road with 70mph speed limit and 120kph design speed. South / east bound it is

effectively a 2 lane rural all-purpose interchange link with 50mph speed limit and 85kph

design speed.

2.4 The A453 north of J24 is currently a 2 lane rural single all purpose road with 100kph

design speed but is in the process of being widened to a dual 2 lane rural all purpose

road with 120kph design speed. This is due to open in mid 2015 and is assumed to be

fully open before this Scheme is constructed.

2.5 The A453 south of J24 is a dual 2 lane all purpose road with 120kph design speed.

2.6 The existing roundabout at J24 is currently being amended as part of the ‘Pinch Point’

funding programme. These works are due to be completed by early 2015 and are

assumed to be completed before this Scheme is constructed.

2.7 The M1, A50 and J24 roundabout have street lighting that is on during all hours of

darkness. The A453 is not lit apart from its immediate approaches to J24.

2.8 The A6 through Kegworth is a single carriageway of varying standard, and south of

Kegworth is a rural dual carriageway until just north of Hathern.

Standards used

2.9 The Scheme layout does not include any managed motorway technology and will thus be

designed in accordance with the following standards:

TA46/97 “Traffic flow ranges for use in the assessment of new rural roads”

TA91/05 “Provision for Non-motorised Users”

TD9/93 “Highway Link Design”

TD16/07 “Geometric Design of Roundabouts”

TD18/85 “Criteria for the Use of Gantries for Traffic Signs and Matrix Traffic Signals

on Trunk Roads and Trunk Road Motorways”

TD22/06 “Layout of Grade Separated Junctions”

TD27/05 “Cross-Sections and Headrooms”

TD41/95 “Vehicular Access to All-Purpose Trunk Roads”

TD42/95 “Geometric Design of Major/Minor Priority Junctions”

TD46/05 “Motorway Signalling”

TD50/04 “The Geometric Layout of Signal-Controlled Junctions and Signalised

Roundabouts”

TD51/03 “Segregated Left Turn Lanes and Subsidiary Deflection Islands at

Roundabouts”

TD69/07 “The Location and Layout of Lay-bys and Rest Areas”

IAN149/11 “Existing Motorway Minimum Requirements”




2.10 The A6 Kegworth Bypass will be designed to the above standards and an assessment of

the bypass is included in this report. However, other local roads will be designed to the

6Cs design guide that is used by Leicestershire County Council (LCC), the local highway

authority. Analysis of the roads designed to the 6Cs standard is not included in this

report.

2.11 The use of the above standards is described in detail in the following chapters.




3.0 HORIZONTAL DESIGN OF LINKS

3.1 The interchange links roads consist of various elements, the link itself and the upstream

or downstream diverge or merge. Each element of each interchange link is analysed

below.


3.2 The link commences at the eastern end of the dual 3 lane all-purpose A50 at the back of

the nose of the diverge of the A50EB to M1NB interchange link. This diverge is

unaffected by the Scheme, but is a Diverge Layout C (lane drop) and it generally meets

the requirements of TD22/06 with the exception of a lack of near straight on the A50 EB

to M1 NB interchange link downstream of the diverge nose. However, as this link is

unaffected by the Scheme a departure is not required.

3.3 The link will be an all-purpose road until the proposed fork, downstream of which it will

be under motorway regulations.

3.4 The design speed for this link is 85kph which is derived from TD22/06 Table 4/1.

Horizontal alignment

3.5 The following table summarises the horizontal alignment elements for the interchange

link. The details of any junction features including merges and diverges are itemised

separately below.

Chainage Element Standard

Proposed Design

Details Relaxations /

Departures

59.533-

102.292m

Transition

curve to

right hand

curve

~85m length

transition curve

designed to 120kph

design speed

(TD22/06 para 4.6)

~43m length

transition

curve to

1440m radius

Relaxation of q to 0.6m

permitted by TD9/93

para 3.16 due to

geometrical constraints

102.292-

276.539m

Right hand

curve

510m desirable min

radius 1440m radius None

276.539-

319.298m

Transition to

straight

No curve needed as

radius is 1440m for

85kph design speed

None

proposed None

319.298-

515.465m Straight None

455.883-

526.983m

Quarry

access

junction

See below See below

515.465-

639.865m

Transition

curve to

right hand

curve

~244m length

transition curve

~122m length

transition

curve


permitted by TD9/93

para 3.16 due to






Proposed Design


Departures

639.865-

828.687m

Right hand

curve

510m desirable min

radius 180m radius

3 steps below desirable

minimum is a permitted

relaxation. Required in

order to provide

junction within overall

land and existing

highway constraints.

However, this

relaxation in

conjunction with the

relaxation for stopping

sight distance noted in

chapter 4 is a

departure from

standard and is dealt

with by departure

application EMG4.

828.687-

953.088m

Transition to

straight

~244m length

transition curve

~122m length

transition

curve


permitted by TD9/93

para 3.16 due to


953.088-

980.006m

Transition to

left hand

curve

~54m length

transition curve

~27m length

transition

curve


permitted by TD9/93

para 3.16 due to


Fork to

develop A50

EB to M1 J24

IL

See below See below

Downstream of the fork the interchange link is under motorway regulations

980.006-

1315.859m

Left hand

curve

510m desirable min


1315.859-

1391.600m Near straight

1020m min radius

over 115m length

Transition

from 810m to

3000m radius

Best fit curve complies

with near straight

requirements

1391.600-

1555.447m

Merge to M1

SB See below See below

Quarry access junction

3.6 The private means of access is designed to TD41/95 which permits direct vehicular

access to all purpose roads of design speed of 85kph or less. The direct access is located

on a straight as noted in the above table. The quarry access is only for vehicles

travelling eastbound on the interchange link and is an access only, with the egress sited

at J24. An egress at this location is not proposed due to the weaving length with the

downstream fork.




3.7 Due to the fact that the quarry access will, by its nature, serve a significant number of

HGVs, and the flow on the main carriageway being significantly greater than 7000 AADT,

it is considered important that an auxiliary lane be provided to allow deceleration to take

place off the main carriageway. It is therefore proposed to design the quarry access in

accordance with TD42/95.

3.8 The provision of an auxiliary lane is proposed for the reasons stated above and follows

the advice given in TD42/95 para 7.56. The 2D geometrical design elements of the

access are summarised in the table below.

Element Standard

Proposed Design


Departures

Direct taper

length 15m 15m None

Deceleration

length 55m 55m None

Fork for A50EB to M1J24 Interchange link

3.9 For the diverge of the A50EB to M1J24 interchange link from the A50EB to M1SB

interchange link, due to the balance of traffic flows, a single lane fork is considered to be

the most appropriate design. Forks are permitted within interchanges and should be

designed to TD22/06 para 4.31. TD22/06 Figure 4/7 gives the appropriate layout.

3.10 The 2D geometrical design elements of the fork are given in the table below.

Element Standard

Proposed Design


Departures

Hardened offside verge

start taper length 40m 40m None

Nose length 40m 40m None

Minimum Nose ratio 1:12 1:8

1:8 is permitted and is

required to allow

downstream

hardshoulder width with

40m nose length, it is

not considered to give

an excessive angle at

the fork.

Hardened offside verge

end taper length 40m 40m None

M1 J24A SB merge

3.11 Traffic flows have been applied to TD22/06 Figure 2/3MW and Layout B or F is required

in the AM or PM peak hour accordingly. The flows are shown on Figure 3.1 of this

report.




3.12 Due to the downstream weaving section, full details of which are given below, 4 lanes are

required downstream of this merge and as such a lane gain is required. Therefore from

TD22/06 Figure 2/3MW, Layout F would be appropriate. However, it is not possible to

construct a Layout F merge within the existing constraints as it would require

reconstruction of the existing bridge at M1 J24. IAN149/11 para 3.3.3 permits Layout E

to be substituted for Layout F as a relaxation. Due to the aforementioned constraints, a

Layout E merge is thus proposed for the Scheme. Note that this will require the

upstream link to have a single lane and this is dealt with in the Cross Sections chapter,

below.

3.13 The 2D geometrical design elements of the Layout E merge are given in the table below.

As this is a new slip road on an existing motorway, IAN149/11 is the relevant design

standard. The near straight is provided as shown above.

Element Standard

Proposed Design


Departures




required to allow

upstream hardshoulder

width with 115m nose

length, it is not

considered to give an

excessive angle at the

merge.

3.14 The location of the merge is upstream from the merge for J24. As such, TD22/06 para

4.30 and Figure 4/5 apply (this is not amended by IAN149/11). This requires a

minimum distance of 3.75V m between the tips of noses for successive merges, where V

is the design speed. The M1 SB design speed is 120kph and therefore a minimum

distance of 450m is required. A distance of 830m is proposed for the Scheme.

3.15 Downstream of the merge the widening of the M1 SB to 4 lanes is assessed under the

paragraph “Widening of M1 SB between J24A merge and J24 merge (D4M for SB)” of this

report. This includes the weaving assessment.

A50EB to M1 J24 interchange link

3.16 This link commences at the end of the fork from the A50EB so M1SB interchange link and

continues to the merge with the M1SB to J24 interchange link. It will be an all-purpose

road throughout.


3.18 The location of the merge with the M1 SB to J24 interchange link is downstream from the

fork from the A50 EB to M1 SB interchange link. As such, TD22/06 para 4.30 and Figure

4/5 apply. This requires a minimum distance of 3.75V m between the tips of noses for

successive merges, where V is the design speed. The interchange link design speed is

85kph and therefore a minimum distance of 319m is required. A distance of 369m is

proposed for the Scheme.







separately below.


Proposed Design


Departures

432.259 –

528.138m

Transition

curve to

straight

(from radius

used at fork)

~172m length

transition curve

≥86m length

transition

curve


permitted by TD9/93

para 3.16 due to


528.138-


Merge with

M1 SB to J24

IL

See below for M1 SB

to J24 IL

See below for

M1 SB to J24

IL

M1SB to J24 interchange link

3.20 This link commences at relocated M1 J24 southbound diverge and continues to the J24

roundabout. It is under motorway regulations until the merge with the A50EB to J24

interchange link and is all-purpose road downstream of this point.





separately below.


Proposed Design


Departures

M1 J24 SB

diverge See below See below

0-


1020m radius over

80m length

1020m radius

over 80m

length

None

116.761-

227.162m

Left hand

curve

510m desirable min


227.162-

257.901m

Transition

curve to

straight

~43m length transition

curve

~30m length

transition

curve

Relaxation of q to

0.42m permitted by

TD9/93 para 3.16 due

to geometrical

constraints





Proposed Design


Departures

257.901-

319.379m

Transition

curve to

right hand

curve


curve

~61m length

transition

curve

Relaxation of q to

0.42m permitted by


to geometrical

constraints

319.379-

544.981m

Right hand

curve

510m desirable min


Merge with

A50 EB to

J24 IL

See below See below

Downstream of the merge the interchange link is an all purpose road

544.981-

606.460m

Transition

curve to

straight


curve

~61m length

transition

curve

Relaxation of q to

0.42m permitted by


to geometrical

constraints

606.460-

667.939m

Transition

curve to left

hand curve


curve

~61m length

transition

curve

Relaxation of q to

0.42m permitted by


to geometrical

constraints

667.939-

752.037m

Left hand

curve

510m desirable min


753.686-

815.165m

Transition

curve to

straight


curve

~61m length

transition

curve

Relaxation of q to

0.42m permitted by


to geometrical

constraints

815.165-

918.227m Straight

M1 J24 SB diverge

3.23 Traffic flows have been applied to TD22/06 Figure 2/5MW and Layout A is required. The

flows are shown on Figure 3.2 of this report.

3.24 The location of the diverge is downstream from the diverge for J24A. As such, TD22/06

para 4.30 and Figure 4/5 apply (this is not amended by IAN149/11). This requires a

minimum distance of 3.75V m between the tips of noses for successive diverges, where V

is the design speed. The M1 SB design speed is 120kph and therefore a minimum

distance of 450m is required. A distance of 620m is proposed for the Scheme.

3.25 Likewise, TD22/06 requires the same distance between the tips of noses for the M1 J24

SB diverge and M1 J24A SB merge. A distance of 678m is proposed for the Scheme.




3.26 The 2D geometrical design elements of the Layout A diverge are given in the table below.

As this is a new slip road on an existing motorway, IAN149/11 is the relevant design

standard. The near straight is provided as shown in the table above.

Element Standard

Proposed Design


Departures

Diverge taper 170m 170m None


Minimum Nose ratio 1:15 1:15 None

M1SB to J24 IL / A50EB to J24 IL merge

3.27 Traffic flows have been applied to TD22/06 Figure 2/3AP and Layout E is required. The

flows are shown on Figure 3.3 of this report. Due to the link becoming all–purpose road

south of the merge, the all-purpose diagram has been used – which is considered to be

more onerous than the motorway diagram.

3.28 The 2D geometrical design elements of the Layout E merge are given in the table below.

Element Standard

Proposed Design


Departures

Nose length within

interchange 75m 75m None

Minimum Nose ratio

within interchange 1:25 1:11.5

1:11.5 is permitted and

is required to allow


width with 75m nose

length, it is not



merge.

Weaving length downstream of interchange link merge

3.29 There is a weaving section on the interchange link between the merge of the M1SB to

J24 IL / A50 EB to J24 IL, and the downstream signalised roundabout.

3.30 The minimum weaving distance for all-purpose roads, as defined by TD22/06 para 4.36

and 4.38, is 1km.

3.31 Based on TD22/06 Figure 4/10, the actual weaving distance proposed, Lact, is 447m.

This is a departure from standard and is dealt with by departure application EMG6.

Full justification is provided in the departure application together with proposed

mitigation measures. The principal reason for this departure is that there is insufficient

space for a longer weaving distance to be provided.

3.32 We note that, although it does not apply to this situation as it is not an existing

motorway, IAN149/11 permits the minimum weaving length to be reduced to the upper




graph in TD22/06 Figure 4.14 (IAN149/11 para 3.4.11). For comparison purposes if this

graph were followed then it would give a minimum weaving length of 250m.

Extension to existing M1SB to A50WB interchange link

3.33 The existing M1SB to A50WB interchange link runs from J24A to the existing roundabout

with the A50. This existing roundabout will be removed as part of the Scheme and thus

this existing interchange link will be extended to meet the M1 J24 to A50WB interchange

link at the existing merge on the A50, just west of the existing roundabout.

3.34 As the existing M1SB to A50WB interchange link is under motorway regulations, the

motorway regulations will be extended to the end of the link as it would be confusing for

drivers if the route standard were to change part way along the link.

3.35 The extension will run from the end of the existing link and will have a 85kph design

speed as required by TD22/06 Table 4/1. Note that the existing link, upstream of the

roundabout, has a 70kph design speed for much of its length as there is a 40mph speed

restriction in place on the existing loop.


3.36 The following table summarises the horizontal alignment elements for the extension of

the interchange link. The details of any junction features including merges and diverges

are itemised separately below.


Proposed Design


Departures

0-


Transition

curve to left

hand curve

No curve needed as

radius is 1440m for

85kph design speed

None

proposed None

130.668-

421.431m

Left hand

curve

510m desirable min


Transition

curve to

straight

No curve needed as

radius is 1440m for

85kph design speed

None

proposed None

3.37 Downstream of the above, the interchange link will use the existing A50 westbound

mainline up to the point where it meets the M1 J24 to A50WB interchange link at the

existing merge. This short section of existing A50 mainline meets the geometrical

standards for this interchange link, with the exception of cross section which is dealt with

below.


3.38 The Scheme will improve the existing M1 J24 to A50 WB interchange link through

removal of the following existing conflicts:

A50 / Church Lane junction

A50 / Direct farm access

A50 / Hilton Hotel private access




A50 / Main Street junction

3.39 These conflicts exist as a result of the history of this section of road as it was the A6 for

many years. As a result of the Scheme there will be no intermediate junctions or direct

accesses between M1 J24 and the downstream merge with the M1 SB to A50 WB

interchange link.

Segregated left turn lane (SLTL) from A453 northbound

3.40 The geometry of this SLTL is dealt with in a separate chapter below.


3.41 The following table summarises the horizontal alignment elements for the improved

interchange link. The proposed alignment follows the existing alignment as noted below.


Proposed Design (existing where

noted)


Departures

Segregated

left turn lane

from A453

See below See below

62.032-

332.372m

Right hand

curve

510m desirable

minimum radius

340m

(existing)

Between 1 and 2 steps

below desirable

minimum – permitted

relaxation due to

alignment constraints.

However, this

relaxation in

conjunction with the

relaxation for stopping

sight distance noted in

chapter 4 is a

departure from


with by departure

application EMG13.

332.372-

461.419m

Transition

curve to

straight

~129m length

transition curve

~129m length

transition

curve

(existing)

None

461.419-


463.827-

585.706m

Transition

curve to left

hand curve

~122m length

transition curve

~122m length

transition

curve

(existing)

None

585.706-

618.793m

Left hand

curve

510m desirable min

radius

360m radius

(existing)

1 step below desirable

min radius – permitted

relaxation due to

alignment constraints





Proposed Design (existing where

noted)


Departures

618.793-

740.671m

Transition

curve to

straight

~122m length

transition curve

~122m length

transition

curve

(existing)

None

740.671-


861.121-

982.999m

Transition

curve to left

hand curve

~122m length

transition curve

~122m length

transition

curve

(existing)

None

982.999-

1238.992m

Left hand

curve

510m desirable min

radius

360m radius

(existing)


min radius – permitted

relaxation due to

alignment constraints

1238.992-

1348.32m

Transition to

left hand

curve with

radius >

1440m

~122m length

transition curve

~122m length

transition

curve

(existing)

None

3.42 As can be seen from the above, the horizontal alignment of the existing interchange link

is generally considered to be acceptable but there is a need for one departure from

standard.


3.43 As noted above, the Scheme will include widening of the M1 Southbound to 4 lanes

between the new merge at J24A and the existing merge at J24. From this point south

the existing motorway is already 4 lanes as far as the diverge for J23A.

3.44 The widening is required as a result of the weaving assessment as discussed below.


3.45 The horizontal alignment of the M1 southbound between the J24A merge and J24 merge

is a long sweeping right hand curve of radius greater than 2880m, which is the minimum

radius that does require elimination of adverse camber or transitions for a 120kph design

speed. As such, no further consideration of the general horizontal alignment is required

M1 J24A SB merge

3.46 The geometry of the M1 J24A SB merge is dealt with above.

M1 J24 SB merge

3.47 Traffic flows have been applied to TD22/06 Figure 2/3MW and the flows plot within

Layouts E (AM) and B (PM), but are both close the boundary with Layout A. The flows

are shown on Figure 3.4 of this report.




3.48 As there will be four lanes upstream, layout E is discounted. Following TD22/06 para

2.29, careful consideration has been given to the flows as to the choice between Layouts

B and A. As the merge is at a point where the mainline gradient is uphill and steeper

than 3%, Layout B is considered appropriate. Note that the criteria of TD22/06 para

4.29(ii) are not met to mean Layout B must be provided, but the gradient is a

consideration in the selection of Layout B for this element of the Scheme.

3.49 For junction capacity reasons, 2 lanes are required to leave the J24 circulatory

carriageway onto the J24 SB merge slip road. A reduction taper will therefore be

required in order for the Layout B merge to be provided, this is assessed in the cross

section chapter below.

3.50 Under TD22/06 para 4.23 the length of the auxiliary lane has been reviewed. The peak

hour traffic flows will be less than 85% of the capacity of this four lane section of

motorway, as such no lengthening is proposed.

3.51 Likewise, under TD22/06 para 4.25 the termination point of the auxiliary lane has been

reviewed. The uphill gradient does not require a climbing lane and, whilst the gradient is

steeper than 2%, the %HGV is less than 10% and the crest is significantly beyond 500m

past the end of the standard auxiliary lane. As such the termination point of the auxiliary

lane is considered to be correct.

3.52 The 2D geometrical design elements of the Layout B merge are given in the table below.

As this is an amended slip road on an existing motorway, IAN149/11 is the relevant

design standard. The near straight is provided as shown referenced below for the M1 J24

SB merge slip road.

Element Standard

Proposed Design


Departures




required to allow


width with 115m nose

length, it is not



merge.

Auxiliary lane length 230m 230m None

Taper length 75m 75m None

Weaving length – J24A to J23A

3.53 The weaving distance between the proposed merge at J24A and existing diverge at J23A,

Lact, will be 2.5km. This is greater than the desirable minimum weaving distance of 2km

under TD22/06 para 4.35 which is the relevant standard for new schemes. However,

weaving calculation is required between the J24A merge and J23A diverge in accordance

with TD22/06 para 2.71.

3.54 The weaving equation (TD22/06 para 2.71) requires 3.87 lanes to be provided in the AM

peak hour, and 4.12 in the PM peak hour. Using these figures and following TD22/06

para 2.72 it is considered that 4 lanes is appropriate between J24A and J23A. As such,




the Scheme includes 4 lanes between the proposed J24A merge and existing J24 merge,

as four lanes already exist between the merge at J24 and diverge at J23A.

Weaving length – J24 to J23A

3.55 An assessment of the weaving length is required between the new merge at J24A,

altered merge at J24 and the downstream diverge at J23A.

3.56 The existing weaving length between the J24 merge and J23 diverge, Lact, is ~1.37km

which is measured in accordance with TD22/06 Figure 4/13 (the existing J24 merge is

Layout F1, the existing J23A diverge is Layout D1).

3.57 IAN149/11 para 3.4.10 states that where Lact is less than 2km, the existing distances

between preceding merge nose top and succeeding diverge nose tip must be maintained.

3.58 As noted above, the existing J24 Layout F1 merge is proposed to be amended to a

Layout B merge. When it is amended the existing nose does not need to be altered and

therefore the criterion set out in IAN149/11 para 3.4.10 is met. However, the weaving

length will be amended because the distance is calculated differently for Layout B

merges. The revised distance, Lactaltd, will be 1.46km an increase of some 90m.

Furthermore the J24 merge will carry less traffic than existing. Therefore the Scheme is

considered to have benefits in provision of increased weaving distances on the M1

southbound.

3.59 It is noted that the minimum weaving distance calculated using IAN149/11 para 3.4.11 is

~500m, and both existing and amended distances are greater than this figure.

3.60 Thus, as the weaving distance between the amended J24 merge and downstream J23A

diverge complies with IAN149, a departure is not required.

Combined weaving length – J24A & J24 to J23A

3.61 The combined effect of the merge at J24A followed by J24, in advance of the J23A

diverge is a situation, as far as weaving is concerned, that is not covered by existing

standards.

3.62 From a review of the VISSIM model, it is considered that a substantial majority of drivers

merging at J24A will have completed their merge onto the M1 prior to the merge at J24.

This being the case, then the J24A merging traffic can be counted as being on the M1

mainline prior to the J24 merge, and no further weaving calculations are necessary.


3.63 With the construction of the Scheme, in particular the free flow A50 EB to M1 SB link, the

existing J24 SB merge will have a reduction in traffic flow over the existing situation and

will therefore be amended to be a single lane. The merge will be Layout B for the

reasons stated above.

3.64 The slip road will have a 70kph design speed in accordance with TD22/06 Table 4/1.


Proposed Design


Departures

0 –






Proposed Design


Departures

Transition

curve to left

hand curve

No curve needed for

radius ≥ 1020m for

70kph design speed

None

proposed None

106.456 -

286.915m

Left hand

curve

360m desirable

minimum radius 1990m None

286.915 -


1020m radius over

115m

> 1020m

radius for over

115m

None

Merge with

M1 SB See above See above

M1 J24 SB merge

3.65 The merge is assessed above under the M1 widening paragraph.

A453 Northbound (South of J24)

3.66 The A453 northbound between J23A and J24 will be amended due to the construction of

the proposed development access / A6 Kegworth bypass junction. The approach to J24

will also be amended with the construction of the segregated left turn lane (SLTL) to the

M1 J24 – A50WB IL.

3.67 The A453 between a point south of the proposed junction, and J24, will have a 50mph

speed limit and the design speed is therefore taken to be 85kph unless stated otherwise

below.

3.68 The following table assess the horizontal alignment of the A453 that is affected by the

scheme. It does not include the SLTL as this is dealt with separately.


Proposed Design


Departures

0-

163.463m

Right hand

curve

1020m desirable

minimum radius

(120kph design speed

changes to 85kph

towards end of the

curve)

2450m None

Transition

curve to

straight

No curve needed for

radius ≥ 1440m for

85kph design speed

None

proposed None

163.463 -






Proposed Design


Departures

281.209 –

600.352m

Proposed

development

access / A6

Kegworth

Bypass

junction

TD50/04 Refer to separate assessment for the

junction design

600.352 –

795.228m

Left hand

curve

510m desirable


795.228 –

830.775m

Transition

curve to left

hand curve

~62m Transition

length

≥31m

Transition

Length


permitted by TD9/93

para 3.16 due to


830.775m

–

1355.362m

Existing

horizontal

alignment

retained

No changes to existing geometry

1355.362

–

1512.474m

Right hand

curve

510m desirable

minimum radius 220m

Between 2 and 3 steps

below desirable

minimum. This is a

permitted relaxation

under TD9/93 para 3.4

Segregated

left turn lane

to A50 WB


SLTL design

Lay-bys

3.69 The existing lay-by close to J24 will be removed as part of the Scheme. It is noted that

this existing lay-by does not conform to the requirements of TD69/07.

3.70 The existing lay-by close to J23A will be retained as part of the Scheme. This is currently

less than 450m from J23A and approx 450m from the Ashby Road junction. Its

proximity to J23A does not conform to the requirements of TD69/07 but this is

unaffected by the Scheme. It will be more than 450m from the proposed A453 /

development access / Kegworth Bypass junction.

A453 Southbound (South of J24)

3.71 The A453 southbound between J24 and J23A will be amended due to the construction of

the proposed development access / A6 Kegworth bypass junction. The exit from J24 will

also be amended with the removal of the third lane that is currently being constructed as

part of the pinch point scheme.

3.72 The A453 between J24 and a point south of the proposed junction will have a 50mph

speed limit and the design speed is therefore taken to be 85kph unless stated otherwise

below.

3.73 The following table assess the horizontal alignment of the A453 that is affected by the

scheme.





Proposed Design


Departures

Existing

horizontal

alignment

retained

No changes to existing geometry

0 –

111.733m

Left hand

curve

510m desirable


111.733 –

471.046m

Proposed

development

access / A6

Kegworth

Bypass

junction


junction design

471.046 -

521.702m

Right hand

curve

510m desirable


521.702 –

593.870m

Transition

curve to left

hand curve

~61m transition length

curve

≥61m

transition

length curve

None

Existing

horizontal

alignment

retained

Note design speed

changes to 120kph No changes to existing geometry

Lay-bys

3.74 The existing lay-by south of J24 will be retained as part of the scheme. TD69/07 para

3.7 requires a lay-by to be 3.75Vm away from a junction or access, where V is the

design speed. As the design speed will be 85kph, the lay-by will need to be 318.75m

away from both J24 and the proposed junction. Assuming the distance is measured from

the start or end of the lay-by taper, for the upstream and downstream respectively, then

the proposed distances are:

Upstream: 372m between exit from J24 roundabout and start of lay-by taper

Downstream: 471m between end of lay-by taper and private means of access (which

is just before the proposed junction)

3.75 It is therefore confirmed that retention of the existing lay-by would not require a

departure from TD69/07. Any signage related to the proposed junction will be provided

after the lay-by to comply with TD69/07 para 3.7.

3.76 The existing lay-by close to J23A will be retained as part of the Scheme. This is currently

less than 450m from J23A and approx 450m from the Ashby Road junction. Its

proximity to J23A does not conform to the requirements of TD69/07 but this is

unaffected by the Scheme. It will be more than 450m from the proposed A453 /

development access / Kegworth Bypass junction.

A6 Kegworth Bypass

3.77 The bypass will run from the A453 west of the M1, by the existing A453 / Ashby Road

junction, to the existing A6. The designs of the junctions are assessed separately.




3.78 The link will be all purpose single carriageway (S2). In accordance with TD9/93 para

1.6, the design speed has been determined by calculating the layout constraint (Lc) and

alignment constraint (Ac). These have been calculated using the methodology contained

in TD9 and are:

Lc: 21

Ac: 10.9

3.79 Using the above factors, a design speed of 100A (100kph Band A) for the link has been

determined using TD9/93 Figure 1.



link. The details of any junction features are itemised separately below. The elements

are analysed heading east.


Proposed Design


Departures

0-246.171m Straight None

162.967m Ashby Road

junction TD42/95

See junction

assessment

below

246.171- 386.259m

Transition

curve to

right hand

curve

~140m length

transition curve

~140m

length

transition

curve

None

386.259-578.365m Right hand

curve

720m desirable

min radius 510m radius

1 step below

desirable min radius

– permitted

relaxation due to

alignment

constraints

575.400-648.409m Transition to

straight

~140m length

transition curve

~70m length

transition

curve

Relaxation of q to

0.6m permitted by

TD9/93 para 3.16

due to geometrical

constraints

648.409-718.453m

Transition

curve to left

hand curve

~140m length

transition curve

~70m length

transition

curve

Relaxation of q to

0.6m permitted by

TD9/93 para 3.16

due to geometrical

constraints

732.536m

Whatton

Road

junction

TD42/95

See junction

assessment

below





Proposed Design


Departures

718.453-911.668m Left hand

curve

720m desirable


1 step below


– permitted

relaxation due to

alignment

constraints


straight

~140m length

transition curve

~70m length

transition

curve

Relaxation of q to

0.6m permitted by

TD9/93 para 3.16

due to geometrical

constraints

981.712-1055.866 Straight None

1055.866-1125.910m

Transition

curve to left

hand curve

~140m length

transition curve

~70m length

transition

curve

Relaxation of q to

0.6m permitted by

TD9/93 para 3.16

due to geometrical

constraints

1125.910-1505.950m Left hand

curve

720m desirable


1 step below


– permitted

relaxation due to

alignment

constraints


straight

~140m length

transition curve

~70m length

transition

curve

Relaxation of q to

0.6m permitted by

TD9/93 para 3.16

due to geometrical

constraints

1575.994-1675.223m

Transition

curve to

right hand

curve

~198m length

transition curve

~99m length

transition

curve

Relaxation of q to

0.6m permitted by

TD9/93 para 3.16

due to geometrical

constraints

1675.223-1683.440m Right hand

curve

720m desirable


2 step below


– permitted

relaxation due to

alignment

constraints

1683.440-


1723.135

London

Road

roundabout

TD16/07

See junction

assessment

below




3.81 Note that relaxations in horizontal alignment are permitted on the immediate approaches

to junctions. TD9/93 para 1.26 only places this restriction on stopping sight distance and

vertical curvature.

3.82 The horizontal alignment does not have any radii in Band C of TD9/93 Figure 24 and the

radii used are considered to be non-overtaking sections.




4.0 SIGHT DISTANCE ON LINKS

4.1 The stopping sight distance is assessed for each of the links identified above. Note that

visibility to traffic signals or roundabout give way lines are assessed separately.


4.2 As noted in chapter 3 above, the design speed is 85kph and thus the desirable minimum

stopping sight distance is 160m as per TD9/93 Table 3. The stopping sight distance

along the link is assessed in the table below. Under TD22/06 para 4.17, from the back of

the M1 SB merge nose the mainline stopping sight distance applies which is 295m.

Chainage

Junction

features within

length

Proposed

SSD Relaxations / Departures

0-

Immediate

approach to

quarry access

junction

≥160m None

455.908-

697.150m None

≥160 to

high object

Min 90m to

low object

2 steps below desirable minimum SSD

is permitted under TD9/93 para 2.8.

However, this relaxation in conjunction

with the relaxation for horizontal

alignment radius noted in chapter 3 is a

departure from standard and is dealt

with by departure application EMG4.

- back of

merge nose

Immediate

approach to fork

and immediate

approach to M1

SB merge

≥160m None

Nose Merge ≥295m None

A50 EB to M1 J24 interchange link



along the link is assessed in the table below.

Chainage

Junction

features within

length

Proposed


0-End

Immediate

approach to

merge with M1

SB to J24 IL

≥160m None

M1 SB to J24 interchange link







Chainage

Junction

features within

length

Proposed


0-End

Immediate

approach to

merge with A50

EB to J24 IL

Immediate

approach to

signalised

roundabout

≥160m None

Extension to existing M1 SB to A50 WB interchange link




Chainage

Junction

features within

length

Proposed


0-End

Immediate

approach to

merge with M1

J24 to A50 WB IL

≥160m None





Chainage

Junction

features within

length

Proposed


0-

441.419m

End of

segregated left

turn lane

120m

1 step below desirable minimum SSD is

permitted under TD9/93 para 2.8.

However, this relaxation in conjunction

with the relaxation for horizontal

alignment radius noted in chapter 3 is a



441.419 –

845.049m None ≥160m None

845.049 –

1419.051m None 120m


permitted under TD9/93 para 2.8. Co-

incident with 1 step below desirable

minimum radius for horizontal

alignment which is considered to be an

acceptable combination of relaxations.




Chainage

Junction

features within

length

Proposed


1419.051 -

End

Immediate

approach to

merge with M1

SB to A50 WB IL

≥160m None


4.7 The design speed of the M1 SB is 120kph and thus the desirable minimum stopping sight

distance is 295m.

4.8 A stopping sight distance of greater than or equal to 295m is already provided on Lane 3

of the existing motorway through Junction 24. This will be maintained as part of the

Scheme. As such there are no relaxations or departures from standard required for

visibility on the M1 southbound as a result of the Scheme.




along the link is assessed in the table below. Under TD22/06 para 4.17, from the back of

the merge nose the mainline stopping sight distance applies which is 295m.

Chainage

Junction

features within

length

Proposed


0 – back of

nose

Immediate

approach to

merge with M1

SB

≥120m None

Nose Merge ≥295m None


4.10 As noted in Chapter 3 above the link will have a design speed of 85kph and the desirable

minimum stopping sight distance is 160m.

Chainage

Junction

features within

length

Proposed


0 –

378.553m

Immediate

approach to

proposed signal

junction

≥160m None

476.204 –





Chainage

Junction

features within

length

Proposed


1272.474 –

1512.474m

Immediate

approach to J24

roundabout and

SLTL

160m None


4.11 As noted in Chapter 3 above the link will have a design speed of 85kph and the desirable

minimum stopping sight distance is 160m.

Chainage

Junction

features within

length

Proposed


0 –


116.300 –

356.300m

Immediate

approach to

proposed

junction

≥160m None

A6 Kegworth Bypass

4.12 As noted in Chapter 3 above the link will be all purpose single carriageway (S2) with a

design speed of 100kph.

4.13 The stopping sight distance in the eastbound direction of the link is assessed in the table

below.

Chainage

Junction

features within

length

Proposed


0-

155.135m

Immediate

approach to

Ashby Road

junction

See vertical alignment assessment

155.135 –


413.036 -

735.536m

Immediate

approach to

Whatton Road

junction

≥215m None

735.536-





Chainage

Junction

features within

length

Proposed


1066.293-

1400.635m None ≥160m


permitted under TD9/93 para 2.8. Co-

incident with 1 step below desirable

minimum radius for horizontal

alignment which is considered to be an

acceptable combination of relaxations.

1400.635-

1723.135m

Immediate

approach to

London Road

roundabout

≥215m None

4.14 The stopping sight distance in the westbound direction of the link is assessed in the table

below.

Chainage

Junction

features within

length

Proposed


1723.135-

168.135m

Immediate

approach to

Whatton Road

junction

≥215m None

168.135-

0m

Immediate

approach to

A453 and Ashby

Road junctions.

See vertical alignment assessment




5.0 VERTICAL ALIGNMENT OF LINKS

5.1 The vertical alignment is assessed for each interchange link as noted below. The design

standards are taken to be TD9/93 and TD22/06 for all links, as amended by IAN149/11

for existing motorways.

5.2 Drawings showing the proposed longsections of the links can be found at Appendix B.


5.3 As noted above the design speed for the interchange link is 85kph.

Chainage

Vertical

alignment

feature

Junction

features in

section

Minimum

Standard

Proposed

Design

Relaxations /

Departures

238.784 –

320.962m Sag curve 20 KF 201 KF None

320.962-

717.581m

Crest

curve

Immediate

approach to

quarry access

55 KF 55 KF None

717.581 –

833.813m Sag curve

Immediate

approach to

fork

20 KF 20 KF None

833.813 –

1001.687m Grade

Immediate

approach to

fork

0.5% to 4% 0.8%

(uphill) None

1001.687

–

1073.576m

Sag curve 20 KF 20 KF None

1073.576

–

1206.766m

Crest

curve 55 KF 30 KF


minimum is permitted

relaxation, this is due

to alignment constrains

of this link passing over

the M1 SB to J24 IL

1206.766

–

1398.403m

Crest

curve

Immediate

approach to

M1 SB merge

55 KF 55 KF None

1398.403

–

1486.520m

Sag curve

Immediate

approach to

M1 SB merge

20 KF 20 KF None




A50EB to M1 J24 interchange link


Chainage

Vertical

alignment

feature

Junction

features in

section

Minimum

Standard*

Proposed

Design

Relaxations /

Departures

378.608 –

586.111m

Crest

curve

Immediate

approach to

merge with

M1 SB to J24

IL

55 KF 55 KF None

586.111 –

640.842m Sag curve

Immediate

approach to

merge with

M1 SB to J24

IL

20 KF 20 KF None

M1SB to M1 J24 interchange link


Chainage

Vertical

alignment

feature

Junction

features in

section

Minimum

Standard

Proposed

Design

Relaxations /

Departures

174.342m –

341.718m Grade 0.5 – 6%

0.5%

(downhill) None

341.718 –

388.128m Sag curve

Immediate

approach to

merge with

A50 EB to

J24 IL

20 KF 20 KF None

388.128 –

493.205m

Crest

curve 55 KF 55 KF None

493.205 –

529.673m Sag curve 20 KF ≥20 KF None

529.673 –

586.707m Grade 0.5 – 6%

1.6%

(uphill) None

586.707 –

684.891m

Crest


684.891 –


752.037 –

918.227m Grade

Immediate

approach to

J24

roundabout

0.5 – 4% 3%

(uphill) None




Extension to existing M1SB to A50WB interchange link


Chainage

Vertical

alignment

feature

Junction

features in

section

Minimum

Standard*

Proposed

Design

Relaxations /

Departures

0-

140.016m

Crest

curve 55 KF 52 KF

Just below desirable

minimum due to

alignment passing over

existing structure,

permitted relaxation.

140.016 –


222.648-

338.363m

Crest


338.363-

476.622m Sag curve

Immediate

approach to

merge with

M1 J24 to A50

WB IL

20 KF 26 KF None

Improvements to existing M1 J24 to A50WB interchange link

5.7 The vertical alignment of this interchange link is dictated by the existing alignment.

There are no prominent crest curves or steep gradients on this alignment.

5.8 Based on the above it is considered that there are no relaxations or departures.


5.9 The M1 southbound alignment will be retained as existing and has a sag curve through

Junction 24 followed by an uphill gradient of approx 3%. The widening of the M1

proposed as part of the Scheme will not include any significant alterations to the vertical

alignment. No existing departures from standard have been identified in relation to

vertical alignment.


5.10 The improvement to the existing slip road will not include any significant changes to the

vertical alignment. No existing departures from standard have been identified in relation

to vertical alignment.





5.11 As noted in Chapter 3 above the link will have a design speed of 85kph.

Chainage

Vertical

alignment

feature

Junction

features in

section

Minimum

Standard

Proposed

Design

Relaxations /

Departures

15.471 –

182.572m

Crest

curve

Immediate

approach to

proposed

junction

55 KF 182 KF None

182.572 –

476.204m Grade

Proposed

junction 0.5-4% 0.5% None

476.204 –

701.307m

Crest

curve None 55 KF 30 KF


minimum Crest K

value. This is a



701.307 –

769.270m Grade None 0.5-4% 8%

Permitted relaxation

under TD9/93 para 4.2.

See detailed

explanation for this

under the A453

Southbound

assessment, below.

769.270 –

836.323m Sag curve None 20 KF 20 KF None

5.12 North of the above, the existing vertical alignment is retained until the roundabout at M1

J24.


5.13 As noted in Chapter 3 above the link will have a design speed of 85kph.

5.14 North of the below, the existing vertical alignment is retained from the roundabout at M1

J24.

Chainage

Vertical

alignment

feature

Junction

features in

section

Minimum

Standard

Proposed

Design

Relaxations /

Departures

0 –


66.996 –

115.219m Grade None 0.5-4% 8%

Permitted relaxation

under TD9/93 para 4.2.

See detailed

explanation for this

below.




Chainage

Vertical

alignment

feature

Junction

features in

section

Minimum

Standard

Proposed

Design

Relaxations /

Departures

115.219 –

230.898m

Crest

curve

Immediate

approach to

proposed

junction

55 KF 30 KF


minimum Crest K

value. This is a



but is not permitted on

an immediate approach

to a junction under

TD9/93 para 1.26. This

is a departure from


with by Departure

EMG9.

230.898 –

407.223m

Crest

curve

Immediate

approach to

proposed

junction

55 KF 55 KF None

407.223 –

462.529m Grade

Proposed

junction 0.5-4% 0.94% None

462.529 –


526.718 –

581.304m Grade None 0.5-4% 1.58% None

5.15 An 8% gradient is proposed for approx 50m on the A453 between the proposed junction

and the existing Junction 24 roundabout. The reason for this is to enable the proposed

junction, which has to tie in to the A6 Kegworth Bypass that will bridge the M1 close to

the junction, to be on a relatively level plane. This is essential to avoid adverse camber

being created at certain points around the junction.

5.16 An 8% gradient is permitted as a relaxation but, as stated in TD9/93 para 4.2, increasing

the gradient above 4% can have an adverse effect on the capacity. The A453

Southbound (i.e. uphill) design flows in the AM and PM peaks are 879vph and 604vph

respectively. The standard capacity for a single lane on an all purpose dual carriageway

is 1600vph, and as the design flows are significantly less than 1600vph, it is not

considered that the 8% would have a detrimental effect on capacity.

A6 Kegworth Bypass

5.17 The design speed is 100kph as noted above and the proposed geometry is assessed as

follows:




Chainage Vertical alignment feature

Junction

features in section - Eastbound

Junction

features in section - Westbound

Minimum

Standard*

Proposed

Design Relaxations / Departures

0 –

320.842m

Crest

curve

Immediate

approach to

Ashby Road

Immediate

approach to

A453

signalised

junction

and Ashby

Road

100 KF 55 KF


minimum crest curve is

permitted under TD9/93

para 4.9 but not on

immediate approach to

junction (TD9/93 para

1.26). A departure from

standard is therefore

required, which is

departure EMG17. This is

explained in detail below.

320.842-

485.608m Sag curve

Immediate

approach to

(but not

including)

Whatton

Road (N)

Immediate

approach to

Ashby Road

junction

26 KF 20 KF

1 step below absolute

minimum sag curve is

permitted but not on



1.26). Co-incident with 1

step below desirable

minimum radius which is

not a permitted

combination under TD9/93

para 1.24. A departure

from standard is

therefore required, which

is departure EMG18. This

is explained in detail

below.

485.608-

1344.655

m

Crest

curve

Immediate

approach to

Whatton

Road (N)

and (S)

Immediate

approach to

Whatton

Road (N)

and (S)

100 KF 100 KF None

1344.655-

1630.238

m

Grade

Immediate

approach to

(but not

including)

London

Road

roundabout

None 0.5-6% 5.2% None




Chainage

Vertical

alignment feature

Junction

features in section - Eastbound

Junction

features in section - Westbound

Minimum

Standard*

Proposed

Design Relaxations / Departures

1630.238-

1694.238

m

Sag curve

Immediate

approach to

(but not

including)

London

Road

roundabout

None 26 KF 20 KF


minimum crest curve is

permitted under TD9/93

para 4.9 but not on



1.26). A departure from

standard is therefore

required, which is

departure EMG19. This

is explained in detail

below.

1694.238-

1723.135

m

Grade

Immediate

approach to

London

Road

roundabout

None 0.4-6% 2% None

Departure EMG17

5.18 A 1 step reduction in Crest K value, from 100 to 55 is proposed. This is on the

immediate approach to a junction and a departure is sought from TD9/93 para 1.26.

This is in order to minimise the height of the embankment to the south west of

Kegworth. The effect of this reduction in Crest K value would be that the object height,

visible at 215m, is 1.05m. This would mean that any vehicle exiting the Ashby Road

junction would be clearly visible to drivers on the Kegworth Bypass at the required

stopping sight distance and vice versa. Queuing traffic on the approach to the A453

signalised junction would also be visible.

5.19 In order to mitigate this departure, a 50mph speed limit is proposed on the bypass

between the A453 signalised junction (which will have a 50mph limit) and to the east of

the Ashby Road junction. This will have the effect of reducing the design speed to 85kph

on this section of the bypass. This is not considered to have a detrimental effect on the

operation of the bypass as it is only proposed close to the A453 junction.

Departure EMG18

5.20 Departure EMG18 is sought in order to minimise the height of the embankment to the

south west of Kegworth. It is therefore sought on environmental grounds. The sag

curve with KF of 20 is not used within the junction itself but is on the immediate

approach to the Whatton Road (N) junction as defined by TD9/93 para 1.26a. The

reduction in sag curve KF is not considered to affect visibility.

5.21 No mitigation is considered necessary as sight lines are not affected.

Departure EMG19

5.22 Departure EMG19 is sought in order to minimise the depth of the cutting and gradient on

the bypass to the south of Kegworth. The sag curve with KF of 20 is not used within the

junction itself but is on the immediate approach to the A6 London Road roundabout as

defined by TD9/93 para 1.26a. The reduction in sag curve KF is not considered to affect

visibility.




5.23 No mitigation is considered necessary as sight lines are not affected.




6.0 CROSS SECTION OF LINKS

6.1 The cross section is assessed for each of the links identified in chapter 3 above.

A50 EB to M1 SB interchange link (IL2C and IL1A)

6.2 The standard cross sections for the interchange link have been determined in accordance

with TD22/06 para 3.4 based on the traffic flows. As the interchange link changes

standard at the fork to the A50 EB to J24 interchange link, the cross section will change

at this point. As noted above, south of the fork motorway regulations will apply and this

will also affect the cross section.

6.3 The traffic flow on the interchange link between the fork and the M1 merge has been

assessed and, following TD22/06 para 3.4, the required section is IL2A. However, due to

the location of the upstream fork and downstream Layout E merge, there is insufficient

length for a 2 lane interchange link to be provided followed by a merge on the link itself,

prior to the merge with the M1. Therefore the proposed cross section is IL1A which

requires a departure from standard and is dealt with by departure application EMG5.

6.4 The details of the cross sections for the interchange link are given in TD27/05 Figures 4-

1b and 4-3c and are summarised as follows:

Section Verge

(m)

Hardshoulder /

hardstrip (m)

Lane 1

(m)

Lane 2

(m)

Hardstrip

(m)

Verge

(m)

IL2C 2.0 1.0 3.65* 3.65* 1.0 2.5

IL2A 1.5 3.3 3.65* 3.65* 1.0 2.0

IL1A 1.5 3.3 3.7 0.7 2.3

* may be reduced to 3.5m in accordance with TD9/93 3.14 where criteria therein apply

6.5 The cross section for the interchange link is analysed below:

Chainage Required

section

Proposed

section Relaxations / Departures

0–

287.244m IL2C IL2C None

287.244-

515.465m IL2C

See drawing

NTH/209/SK65

Reduction in NMU route width over

structure and reduction in offside verge

width mean that the cross section

requires a departure from standard

and is dealt with by departure

application EMG1.

515.465-

973.683m IL2C IL2C None

1014.616 –

1438.907m IL2A IL1A

requires a departure from standard

and is dealt with by departure

application EMG5




A50 EB to M1 J24 interchange link (IL1C)

6.6 The proposed cross sections for the interchange link have been determined in accordance

with TD22/06 para 3.4 based on the traffic flows and the required section is IL1C. The

details of the cross section for the interchange link ia given in TD27/05 4-3c and are

summarised as follows:

Section Verge

(m)

Hardshoulder /

hardstrip (m)

Lane 1

(m)

Lane 2

(m)

Hardstrip

(m)

Verge

(m)

IL1C 2.0 3.3 3.7 0.7 2.8

6.7 Cross section IL1C is provided in accordance with TD27/05 for the entire length of the

interchange link.

M1 SB to J24 interchange link (IL1A and IL2C)


with TD22/06 para 3.4 based on the traffic flows. As the interchange link changes

standard at the merge with the A50 EB to J24 interchange link, the cross section will

change at this point. As noted above, north of the merge motorway regulations will

apply and this will also affect the cross section.

6.9 The details of the cross sections for the interchange link are given in TD27/05 Figures 4-

1b and 4-3c and are summarised as follows:

Section Verge

(m)

Hardshoulder /

hardstrip (m)

Lane 1

(m)

Lane 2

(m)

Hardstrip

(m)

Verge

(m)

IL2C 2.0 1.0 3.65* 3.65* 1.0 2.5

IL1A 1.5 3.3 3.7 0.7 2.3



Chainage Required

section

Proposed


0 –

(diverge to

merge)

IL1A IL1A None

(merge to

junction

approach)

IL2C IL2C None

6.11 On the immediate approach to the Junction 24 roundabout, three lanes are provided and

these are designed in accordance with the relevant junction standards.

Extension to existing M1 SB to A50 WB interchange link (IL2A)

6.12 The existing interchange link has a cross section of IL2A with the exception of the length

over the Warren Lane bridge up to the J24A roundabout, which has a cross section that




complies with the paved width of IL2C. This is an existing departure that is affected by

the scheme.

6.13 As noted above the interchange link will be under motorway regulations throughout its

length.

6.14 As the interchange link is greater than 1km a single lane interchange link is not

permitted (TD22/06 para 4.3), hence the correct cross section is IL2A. The details of the

cross section of the interchange link is given in TD27/05 Figures 4-1b and is summarised

as follows

Section Verge

(m)

Hardshoulder /

hardstrip (m)

Lane 1

(m)

Lane 2

(m)

Hardstrip

(m)

Verge

(m)

IL2A 1.5 3.3 3.65* 3.65* 1.0 2.0


Chainage Required

section

Proposed


0–

223.929m IL2A

See drawing

NTH/209/SK65

Reduction in hardshoulder width, offside

verge width and verge width mean that

the cross section requires a departure

from standard and is dealt with by

departure application EMG2.

223.929-

386.593m IL2A IL2A None

386.593-

476.622m IL2A

See drawing

NTH/209/SK102

Reduction in hardshoulder width means

that the cross section requires a



6.16 As this is an existing motorway IAN149/11 applies. However, chapter 4 which deals with

cross sections, does not affect the standards for interchange links (para 4.1.2). As such,

para 4.7.3 which states that lengths of discontinuous hardshoulder must be limited to

30% of the relevant link length, does not apply to this interchange link. For reference,

the total link length is 1.6km of which 595m has a discontinuous hardshoulder, which is

37%. It is considered that the discontinuities are adequately addressed by departures

EMG2 and EMG3 noted above.

Improvements to existing M1 J24 to A50WB interchange link (IL2C)

6.17 The existing interchange link has a standard cross section that would meet D2UAP (dual

2 lane urban all-purpose road), but it is a rural all purpose road. One carriageway of the

D2UAP cross section does not meet the requirements which, as the link is longer than

1km, should be IL2C based on TD22/06 para 4.3.

6.18 The Scheme will improve the interchange link through removal of four junctions or direct

accesses as noted in Chapter 3 above. However, it is not proposed to upgrade the

entirety of the existing link. As the Scheme will affect the interchange link departures

from standard will be required for the existing issues.

6.19 The required cross section is IL2C which is defined as follows (TD27/05 Figure 4-3c):




Section Verge

(m)

Hardshoulder /

hardstrip (m)

Lane 1

(m)

Lane 2

(m)

Hardstrip

(m)

Verge

(m)

IL2C 2.0 1.0 3.65* 3.65* 1.0 2.5


6.20 The cross section for the interchange link is analysed below, refer to drawing

NTH/209/SK83 for proposed cross sections.

Chainage Required

section

Proposed


0 –

316.62m IL2C

IL2C (with SLTL as

necessary) None

316.62 –

462.505m IL2C

As IL2C but has

kerbs and no

nearside or offside

hard strip (as

existing)

Lack of hardstrips means that the cross

section requires a departure from

standard and is dealt with by


462.505 –

565.214m IL2C

As IL2C but has

nearside kerb and

no nearside hard

strip (as existing

on nearside)

Lack of nearside hardstrip means that




565.214 –

973.869 IL2C

As IL2C but has

kerbs and no

nearside or offside

hard strip (as

existing)





973.869 –

1047.050m IL2C

As IL2C but has

nearside kerb and

no nearside hard

strip (as existing

on nearside)

Lack of nearside hardstrip means that




1047.050 –

1145.063m IL2C

As IL2C but has

kerbs and no

nearside or offside

hard strip (as

existing)





1145.063

to merge

with M1 SB

to A50 WB

IL

IL2C IL2C None

Widening of M1 SB between J24A merge and J24 merge (D4M for SB)

6.21 The existing M1 southbound between J25 and the merge at J24 is a 3 lane motorway and

the cross section complies with D3M. As noted above the Scheme will widen the M1

southbound to 4 lanes between the proposed merge at J24A to the existing merge at




J24, a distance of some 710m (excluding the J24A merge itself). The required cross

section is D4M, but as this is an existing motorway, the relevant standard is IAN149/11.

IAN149/11 permits relaxations to the cross section without the need for departures from

standard to be obtained.

6.22 As a starting point, required under IAN149/11 para 4.2.2, the required cross section is

D4M which is defined as follows (TD27/05 Figure 4-1a):

Section Verge

(m)

Hard

shoulder

(m)

Lane 1

(m)

Lane 2

(m)

Lane 3

(m)

Lane 4

(m)

Hard

strip

(m)

Central

reserve

(m)

D4M 1.5 3.3 3.65 3.70 3.70 3.65 0.7 3.1

6.23 The existing central reserve width, excluding hard strips, on the M1 southbound in the

vicinity of the scheme is generally 2.5m wide. This is a permitted relaxation under

IAN149/11 Table 4-1 Priority 2, which permits a central reserve width excluding hard

strips of 2.0m. As such the widening of the M1 southbound, except at the locations

identified below, will comply with D4M with the reduced central reserve width.

6.24 The cross section for the M1 southbound is analysed below:

Chainage

(Marker

Posts)

Required

section

Proposed


185/636.046

–

185/496.973m

D4M

D4M with reduced

central reserve

width of 2.5m

Permitted relaxation under

IAN149/11 Table 4-1 Priority 2

185/496.973

–

185/325.003m

D4M IAN149/11 Table

4-1 Priority 11

Use of this section requires a

departure from standard and is

dealt with by departure application

EMG8.

185/325.003

–

185/265.407m

D4M

IAN149/11 Table

4-1 Priority 11 but

with full width

hardshoulder




EMG8.

185/265.407

–

185/084.885m

D4M IAN149/11 Table

4-1 Priority 11




EMG8.

(to M1 J24 SB

merge) D4M

D4M with reduced

central reserve

width of 2.5m

Permitted relaxation under

IAN149/11 Table 4-1 Priority 2

(J24 SB

merge)

D4M plus

Layout B

merge

D4M plus Layout

B merge with

reduced

hardshoulder

width

Requires a departure from


departure application EMG10 (does

not comply with TD27/05 para 4.9.6)

6.25 IAN149/11 para 4.7.3 states that discontinuities of the hardshoulder must be limited to

30% of the link length. The length of the M1 SB between the J24A merge and J24 merge

is 710m as noted above.




6.26 IAN149/11 is unclear as to whether or not a ‘discontinuity’ includes the hatching of the

hardshoulder on the approach and exit from the constraint as shown on Figure 4-2. The

following table summarises the length of the discontinuity based on two methods of

calculation – including and excluding hatching where the hardshouler is 3m wide of

greater.

Length of

hardshoulder less

than 3m width

% of total link length

Including hatched areas

as part of ‘discontinuity’

174m (north bridge)

184m (south bridge)

Total: 358m

50%

Excluding hatched areas

as part of ‘discontinuity’

108m (north bridge)

118m (south bridge)

Total: 358m

32%

6.27 In either method of calculation, the length of discontinuity will be greater than 30% of

the link length and requires a departure from standard – this is dealt with by


Improvement to M1 J24 SB merge slip road (MG1A)


with TD22/06 para 3.4 based on the traffic flows and the required section is MG1A.

However, as a result of the junction capacity analysis, two lanes are required to leave the

upstream junction 24 roundabout. The existing slip road has two lanes with

hardshoulder but does not conform to MG2C. This is an existing departure from standard

that is unchanged by this scheme.

6.29 A slip road reduction taper between the existing cross section (substandard MG2C) and

required cross section MG1A will be provided prior to the Layout B merge. The slip road

reduction taper will comply with IAN149/11 para 3.3.7. From the point where the slip

road reduction taper commences, a standard 3.3m wide hardshoulder will be provided

and where the slip road has a single lane it will comply with MG1A plus the required

offside hatching to comply with IAN149/11 para 3.3.7.

A453 (South of J24)

6.30 The existing cross section for the A453 south of J24 is D2AP. With the exception of the

junction features, this cross section will be retained as part of this Scheme.

A6 Kegworth Bypass (S2)

6.31 From a review of TA46/97 Table 2.1, against the predicted opening year AADT flow of

15,000 vehicles (west of Whatton Road), a Wide Single 2 (WS2) lane carriageway is

suggested. However, TA46/97 does say that the flow ranges should be used flexibly.

There are safety issues associated with WS2 roads and it is not considered desirable to

design the bypass to this standard.

6.32 As a result of the above, a single 2 lane carriageway (S2) has been assessed using the

VISSIM modelling and this shows that the bypass will perform well during the peak hours

– refer to Report TMR4.




6.33 The A6 Kegworth Bypass will be a rural all-purpose road and will have a cross section

that complies with S2 (TD27/05 Figure 4-3a).

6.34 With the exception of junction features, which are assessed separately, cross section S2

is provided throughout the length and thus no relaxations or departures are required for

the cross section. A footway / cycleway is proposed on the northern side of the link.

Climbing lanes

6.35 Consideration to the provision of a climbing lane is required on single carriageway roads

and these affect the cross section. The maximum gradient proposed on the bypass is

5.2%, which is below the 6% desirable maximum gradient (TD9/93 para 4.1).

6.36 TD9/93 para 5.9 states that a climbing lane can be considered if it can be justified where

there is a gradient steeper than 2% for more than 500m. This occurs in the westbound

direction at the eastern end of the bypass. In this location, there is a vertical rise of

28.5m over a distance of 660m.

6.37 TD9/93 requires a minimum length of climbing lane of 500m followed by a further 220m

past the point where the gradient reduces below 2%, followed by 200m of tapers.

Junctions are not permitted within the extents of climbing lanes or tapers. The Whatton

Road (S) junction is approximately 790m from the London Road roundabout, and only

some 100m past the point where the gradient drops below 2%. A climbing lane could,

therefore, not be provided in accordance with the requirements of TD9/93.

6.38 For single carriageways, there is a safety benefit in providing a climbing lane as they

permit overtaking. However, as noted in the chapter below, the overall route already

includes overtaking sections and as good overtaking opportunities exist on both sides of

the bypass, it is not required to provide one on the bypass itself.

6.39 As a result of the above analysis it is considered that there is insufficient justification to

provide a climbing lane on the Kegworth Bypass.




7.0 M1 JUNCTION 24 ROUNDABOUT

General Layout

7.1 The layout of the roundabout complies with TD50/04. Lane widths have been widened

around the gyratory as necessary in accordance with TD42/95 Table 7/2.

7.2 Three lanes are shown over the south bridge – these are being constructed as part of the

pinch point scheme and require departures from standard that have been obtained by

others. This Scheme does not affect this section of the junction.

Visibility requirements for signals

7.3 With the exception of the local access road to Lockington, all entries to the roundabout

will be signal controlled. TD50/04 Paras 2.6 & 2.7 require that desirable minimum

stopping sight distance is provided on the immediate approach to the junction and this

shall include at least one primary traffic signal associated with each movement. The

visibility on the approaches are assessed below:

Approach

Design

speed (kph)

Des min

SSD (m)

Actual SSD

provided (m)

Departure from

standard?

A453 SWB 120 295 ≥ 295 No

A50 EB / SB with M1 SB 85 160 ≥ 160 No

A6 NB 85 160 ~80m

Yes – existing

departure unaffected by Scheme

M1 NB 70 120 ≥ 120 No

A453 NB 85 160 ≥ 160 No

7.4 Junction intervisibility will be provided at all traffic signals in accordance with TD50/04

para 6.11.

Local access road from Lockington

7.5 The local access road from Lockington, and the Hilton Hotel, will run along the line of the

existing A50 SB between J24A and J24. It will function as a priority controlled junction

onto the J24 roundabout and as such has to be designed in accordance with TD16/07.

The various geometrical parameters are assessed below. The design speed for this local

access road is 85kph.

Requirement Criteria Actual

provided

Departure from

Standard?

Visibility on approach 160m 86m Yes, departure

EMG22 – see below

Visibility on entry

70m at 15m

back from give way line

≥ 70m at 15m


No

Visibility to right on entry

70m from give

way line and

15m back from give way line

≥ 70m in both

circumstances No

Entry path curvature ≤ 100m ~ 65m No





provided

Departure from

Standard?

Entry angle 20º to 60º 44 º Guidance as criteria

not in black box

Entry radius 20m 20m Guidance as criteria

not in black box

Lane width on entry 3-4.5m 4.5m No

Departure EMG22

7.6 This is required due to the existing land constraints. The existing A50 SB approach to

the J24 roundabout does not have sufficient visibility on the approach and no land is

proposed to be taken from the hotel as part of the Scheme.

7.7 It is not considered that this departure will give rise to any significant issues as the local

access road will be lightly trafficked. As mitigation, suitable warning signs will be erected

in advance of the junction.

A50 to A453 NB SLTL

Consideration of segregated left turn lane (SLTL)

7.8 Serious consideration has been given to the provision of a segregated left turn lane

(SLTL) from the A50 – M1 J24 interchange link onto the A453 northbound. Whilst this

would be of little purpose in the existing situation as there is very little traffic from the

M1 SB to A453 NB, with the construction of the A50 to M1 interchange link, a SLTL for

A50 EB to A453 NB traffic could be appropriate.

7.9 The traffic flow data for the A50 entry arm to J24 is as follows:

AM PM

Left turning flow (vph) (L) 371 562

Total entry arm flow (vph) (F) 1869 1378

Number of lanes (E) 3 3

F / E 623 459

Is L > (F / E) ? No Yes

7.10 It can therefore be seen from the above that, following TD51/03 para 2.8, a SLTL should

be considered. However, even in the PM peak, L – F/E is less than 100 vehicles so it is

marginal.

7.11 The detailed traffic modelling for the junction has determined that a SLTL would not

improve overall junction capacity as it would deny the opportunity to provide a 3 lane

exit from the J24 circulatory carriageway onto the A453 NB.

7.12 If a SLTL were to be provided then it would need to have a merge exit onto the A453

whereas a dedicated lane would be preferred.

7.13 The proposed quarry egress joins J24 at the point where a SLTL would be located

resulting in an unusual situation.

7.14 For the above reasons, a SLTL is not included within the design.




A453 NB to A50 SLTL

Traffic flows

7.15 A segregated left turn lane (SLTL) is proposed from the A453 Northbound onto the M1

J24 – A50 WB interchange link.

7.16 The traffic flow data for the A453 NB entry arm to J24 is as follows:

AM PM




F / E 400 552

Is L > (F / E) ? Yes Yes


be considered. The detailed traffic modelling for the junction has determined that a SLTL

would improve overall junction capacity.

7.18 The SLTL is located at the end of a downhill gradient on the approach to the M1 J24

roundabout. However, the gradient on the immediate approach (as defined by TD51

para 2.29 and TD9) is less than 1% which is acceptable.

2D geometric Design – General Principles

7.19 The entry radius of the SLTL is 60m and the exit radius is 90m. From TD51/03 Table

2/1, a SSD of 120m should therefore be used in the design.

7.19.1 As the roundabout is to be signalised, and a controlled crossing provided, a physical

island is required for the SLTL.

7.20 The physical island length is approx 105m and therefore, from TD51/03 Table 2/2, the

carriageway width is determined to be 6.7m at the entry radius. As the exit radius is

larger than the entry radius, the width can be reduced in accordance with TD51/03 para

2.22. The SLTL width will therefore reduce to 6.4m at the exit radius.

7.21 However, a 3.5m lane width, as required by TD51/03 para 2.20, will be provided with the

nearside hatched accordingly.

7.22 A cycle lane along the SLTL is not proposed as there are no cycle facilities on the

upstream or downstream links. A wider review of cycle routes has been undertaken and

a route will be provided via the main development site and Lockington, thus avoiding the

busy J24 area completely.

7.23 There are no NMU crossings proposed on the SLTL and it will therefore operate in “free

flow” conditions at all times.

7.24 As the verge width for an D2AP cross section (i.e. the approach) and IL2C cross section

(i.e. the exit) is 2.5m in both scenarios, a verge width of 2.5m is proposed alongside the

SLTL.




2D Geometric Design – Approach Layout

7.25 Following analysis of the flows it is considered that a dedicated lane on the approach will

provide the most suitable solute on.

7.26 The design speed of the approach is 85kph as a 50mph limit is proposed between J24

and the A453 / Site access / Kegworth Bypass junction. Using TD51/03 Table 2/5 an

entry taper length factor of 25 is therefore required. Following TD51/03 para 2.42 the

length of the entry taper is the greater of:

25 x the widening for HGVs, which is 25 x 3.2 = 80m

25 x (island width + 2 x 0.3m) which is 25 x (1.8 + 0.6) = 60m

7.27 An entry taper length of 80m is therefore required and this is included within the Scheme

design.

7.28 The widening for the HGVs is developed along the length of the entry taper as required

by TD51/03 para 2.42.

7.29 Due to the presence of traffic signals on the circulatory carriageway, the SLTL island

commences well in excess of the minimum 1.5m required by TD51/03 para 2.26.

2D Geometric Design – Exit Layout

7.30 The following is a summary of the design flows for the exit layout onto the M1J24 to A50

WB interchange link:

AM PM

From A453 NB 1255 1736

From J24 circulatory carriageway 1303 1320

7.31 Following a review of the above flows a dedicated SLTL exit lane is proposed. Two lanes

are required onto the exit from the J24 circulatory carriageway and, as there are only

two lanes on the downstream link, in order for the SLTL to have a dedicated lane a

merge on the exit from the roundabout is required.

7.32 The merge on the exit from the circulatory carriageway is designed in accordance with

TD51/03 para 2.51. The merge is completed prior to the end of the exit taper of the

SLTL, as required by this same paragraph.

7.33 The design speed of the exit is 85kph as determined by TD22/06 Table 4/1 for the M1J24

to A50 WB interchange link. Using TD51/03 Table 2/5 an exit taper length factor of 25 is

therefore required. Following TD51/03 para 2.42 the length of the exit taper is the larger

of:

25 x the widening for HGVs, which is 25 x 2.5 = 62.5m

25 x (island width + 2 x 0.3m) which is 25 x (1.5 + 0.6) = 52.5m

7.34 An exit taper length of 62.5m is therefore required and this is included within the

Scheme design.

7.35 The widening for the HGVs is removed along the length of the exit taper as required by

TD51/03 para 2.49.

7.36 Due to the merge on the exit from the circulatory carriageway, the SLTL island ends well

in excess of the minimum 6m required by TD51/03 para 2.26.




Abnormal Load Bay

7.37 An abnormal load bay is proposed within the roundabout island. There are no specific

standards for abnormal load bays and they are found within roundabout islands

elsewhere on the network (such as at M6 J16).

7.38 This abnormal load bay is to replace the existing facility on the A50 east / southbound,

between J24A and J24, which will be cut off from the trunk road as a result of the

Scheme. The relocated bay will make use of part of the J24 pinch point scheme that is

currently under construction.

7.39 The relocated abnormal load bay will be provided with gates to deter inappropriate use

and a traffic regulation order will be used to enforce it. The details will be agreed with

the Highways Agency during the detailed design stage for the scheme.




8.0 A453 DEVELOPMENT ACCESS / A6 KEGWORTH BYPASS JUNCTION

8.1 The layout of the signalised roundabout complies with TD50/04. Lane widths have been

widened around the gyratory as necessary in accordance with TD42/95 Table 7/2.

Visibility requirements for signals

8.2 All entries to the roundabout will be signal controlled. TD50/04 Paras 2.6 & 2.7 require

that desirable minimum stopping sight distance is provided on the immediate approach

to the junction and this shall include at least one primary traffic signal associated with

each movement. The visibility on the approaches are assessed below:

Approach

Design

speed

(kph)

Des min

SSD (m)

Actual SSD

provided

(m)

Departure from

standard?

A453 SB 85 160 ≥ 160 No

A453 NB 85 160 160 No

A6 (Kegworth Bypass) 85 160 ≥ 160 No

Development access 60 90 ≥ 90 No

8.3 Junction intervisibility will be provided at all traffic signals in accordance with TD50/04

para 6.11.




9.0 A6 KEGWORTH BYPASS JUNCTIONS AND FEATURES

Overtaking opportunities

9.1 Due to the alignment of the bypass, which results from various constraints such as the

East Midlands Airport landing lights and general topography, the entire bypass is

considered to be a non-overtaking section and has been designed as such.

9.2 For single carriageway roads, TD9/93 para 7.20 requires an overtaking value of 30% to

be achieved for a Category 3 road (The bypass is considered to be a Category 3 road as

defined by TD9/93 Table 4). However, this only applies to new roads over 2km in length

which does not apply to the Kegworth Bypass.

9.3 TD9/93 para 7.23 does apply to this scheme. It is noted that the existing A6 is dualled

from a short way south of the eastern end of the proposed bypass to just north of

Hathern, and that the A453 is a dual carriageway where it runs parallel to the M1. North

of J24 all of the routes (A50, A453 and M1) are dual carriageways allowing overtaking.

It is therefore considered that there are contiguous sections of route that provide good

overtaking opportunities.

9.4 Due to the presence of roundabout junctions at either end of the bypass, it is not

considered that a lack of overtaking on the bypass itself will present a discontinuity of

the route. It is considered that the bypass will be of a much higher standard than the

existing single carriageway through Kegworth.

Ashby Road Junction

9.5 The connection to Ashby Road is designed in accordance with TD42/95. It is designed as

a rural simple junction as its use will be restricted to buses only.

9.6 The visibility standards used are an x distance of 4.5m and a y distance of 160m (to the

right) and 215m (to the left). The y distances vary as the Kegworth Bypass has a design

speed of 85kph (with 50mph speed restriction) between the A453 and this junction and

100kph between this junction and the existing A6. A relaxation in the x distance from

9m to 4.5m is permitted under TD42/95 para 7.8.

Whatton Road Junction

9.7 The connections to Whatton Road (north and south) are designed in accordance with

TD42/95. They are designed as a rural ghost island staggered crossroads junction.

Nearside diverging and merging tapers are not required.

9.8 The visibility standards used are an x distance of 9m and a y distance of 215m (as the

Kegworth Bypass has a design speed of 100kph). These comply with TD42/95 paras 7.3-

7.6.

9.9 The corner radii used are 15m with 30m tapers, as advised by TD42/95 para 7.17. A

channelising island is provided on the minor (Whatton Road) approaches.

9.10 The through lane widths used on the main carriageway are 3.65m and the turning lane

width is 3.5m.

9.11 The turning length, direct taper length and deceleration length are 10m, 25m and 80m

respectively, and are all in accordance with TD42/95.




Farm access points

9.12 Direct access points into farmland are proposed from the Kegworth Bypass at 3 locations.

These will be generally designed to TD41/95 Layout 1. The visibility requirements are

assessed as follows:

Location Visibility splay

provided

Forward

visibility

restrictions

Land north of bypass, east of

Whatton Road 2.4m x 215m None

Land south of bypass, east of


Land north of bypass, east of


9.13 It is considered that relaxation of the x distance to 2.4m is appropriate given the low

usage of these accesses.

Non-motorised user (NMU) crossing points

9.14 Two NMU crossings are proposed over the Kegworth Bypass away from the junctions at

either end. These are at a) Whatton Road and b) Footpath L54.

9.15 The 2-way AADT for the bypass east of Whatton Road is approx 12,000. Under TA91/05

Table 6/1, this would mean that an at-grade crossing would be on the borderline

between “potentially appropriate” and “not normally appropriate”. It is therefore

proposed to provide a central refuge island at both crossing points which would result in

an at-grade crossing being assessed as “normally appropriate”.

A6 London Road roundabout

Consideration of segregated left turn lane (SLTL)

9.16 The traffic flow data for the A6 NB entry arm to the roundabout is as follows:

AM PM




F / E 489 503

Is L > (F / E) ? Yes Yes


be considered. Following a review of the traffic flows, it is considered that a SLTL will

give no benefit as it is a three arm roundabout and the left turn flow would need to give

way to the same right turning flow whether it is within the roundabout or at the give way

at the end of the SLTL. This is because a give way exit to the SLTL would be required as

there is only a single lane in each direction on the Kegworth Bypass (i.e. the layout has

to comply with TD51/03 para 2.48)

9.18 Furthermore, a SLTL would result in additional crossing requirements for NMUs which can

be avoided with a standard roundabout design.




Review of roundabout geometry

9.19 The geometric parameters for the roundabout are assessed below for each approach.

The roundabout ICD is 50m.

Approach from Kegworth (Design speed: 60kph)


provided

Departure from

Standard?

Visibility on approach 90m ≥ 90m No

Visibility on entry

40m at 15m


≥ 40m at 15m


No


40m from give

way line and

15m back from

give way line

≥ 40m in both

circumstances No

Entry path curvature ≤ 100m < 100m No

Entry angle 20º to 60º 42º Guidance as criteria

not in black box


not in black box

Lane width on entry 3-4.5m 2 x 3m No

Approach from Kegworth Bypass (Design speed: 100kph)

Requirement Criteria Actual provided

Departure from Standard?

Visibility on approach 215m ≥ 215m No

Visibility on entry

40m at 15m

back from give

way line

≥ 40m at 15m

back from

give way line

No


40m from give

way line and


≥ 40m in both

circumstances No



not in black box


not in black box


Approach from Loughborough (Design speed: 85kph – see below)


provided

Departure from

Standard?

Visibility on approach 160m 160m No




Approach from Loughborough (Design speed: 85kph – see below)


provided

Departure from

Standard?

Visibility on entry

40m at 15m


≥ 40m at 15m


No


40m from give

way line and


≥ 40m in both

circumstances No



not in black box


not in black box


9.20 The design speed on the approach from Loughborough is taken to be 85kph as it is

proposed to provide a 50mph speed limit from the end of the dual carriageway up to the

proposed roundabout. This is because there is an existing accident problem where the

dual carriageway reverts to single carriageway near the Otter public house. In terms of

the Scheme, this will permit the forward visibility on the approach to the roundabout to

be 160m without a departure.




10.0 MOTORWAY SIGNALLING AND SIGNAGE

10.1 Motorway signalling is present on the M1 corridor and on the A50 immediate approach to

J24A. The M1 southbound between J24 and J23a has gantry mounted lane signalling

(GMLS) together with strategic MS3 VMS signs related to the J23A diverge (for the A42).

Upstream of J24A the M1 southbound has strategic MS3 VMS signs.

10.2 The A50 immediate approach to J24A has GMLS.

10.3 TD46/05 is the standard for provision of motorway signalling but this has been

substantially altered by IAN149/11 for existing motorways.

10.4 The Scheme will affect the motorway signalling on the M1 southbound from north of the

J24A diverge to south of the J24 merge. It will also have an effect on the A50 eastbound

approach.

M1 Southbound

Review of existing signalling provision

10.5 Lane Signals are provided on the immediate approach to J24, through J24 and until after

the J23A diverge. These are control signals and do not display variable message speed

limits (VMSL). The signals are all gantry mounted (with the exception of start of entry

slip road control signals). The gantries do, however, have standard 2 line VMS mounted

on them.

10.6 Strategic 3 line MS3 signs are provided on the M1 southbound approach to J23A and

J24A.

10.7 Gantry mounted lane signals (GMLS) and VMS are currently located as follows:

Signal

type Location

Marker

Post (MP)

Meets

requirements

of IAN149/11

Existing

departures

Strategic

VMS

300m in advance of

Primary DS for J24A Unknown Yes None

Strategic

VMS

200m in advance of

Secondary DS for J24A Unknown Yes None

GMLS +

VMS

None provided at

Primary DS for J24 n/a No Yes

GMLS +

VMS

730m in advance of M1

SB J24 exit datum point 186/7B-25 No

Yes, should be

between 785m and

885m in advance of

exit datum point

(for ½ mile

secondary sign)

GMLS +

VMS

230m in advance of M1

SB J24 exit datum point 186/2B-50 No

Yes, should be at

exit datum point

GMLS +

VMS

M1 SB J24 exit

confirmatory signal 185/7B-30 Yes None




Signal

type Location

Marker

Post (MP)

Meets

requirements

of IAN149/11

Existing

departures

Strategic

VMS

M1 SB intra junction

J24 (but is related to

J23A) ~1890m before

J23A diverge exit

datum

185/2B-15 Yes None

GMLS +

VMS

intra junction J24 just

before J24 merge 184/9B+50

Yes as GLMS

spacing >

1200m

None

GMLS +

VMS

~70m beyond J24

merge / ~1120m

before J23A diverge

exit datum

184/4B+20

No (for signal

after the

merge)

Yes (for ⅔ mile

before J23A

diverge)

Yes as signal should

be 300m beyond

merge entry datum

point

Strategic

VMS

M1 SB strategic VMS

for J23A, ~900m before

exit datum

184/2B+5

Yes (in relation

to downstream

⅓ mile GMLS)

GMLS +

VMS

~550m before J23A

diverge exit datum 183/8B+43

Yes (for ⅓ mile

before J23A

diverge)

10.8 It is also noted that there is no 1 mile or ⅔ mile GMLS on the approach to J24 which is a

departure from IAN149/11 para 5.6.3 which requires lane signals at the primary direction

sign. It is, however, noted that this is complicated by the upstream diverge for J24A.

10.9 IAN149/11 para 5.6.1 has amended TD46 with regards to requirements for lane signals.

TD46 required their use on all 4 lane motorways but they are now only located in certain

locations. However, one of these situations is “On the approaches to strategic road

network interchanges, where a diversion route is available”. It is considered that this

applies to the J24 SB diverge.

Proposed signalling

10.10 It is proposed to retain the lane control signals on the M1 southbound approach to J24 as

the parallel A453 functions as a diversion route. There is no requirement for these to be

upgraded to Variable Message Lane Signals (VMLS) as the Scheme will not include part

or full time running of the hardshoulder. As noted above, departures for reduced cross

section will be sought where a hardshoulder cannot be provided. It is noted that control

signals are provided on the M1 southbound to J23A and retention of the signals on the

approach to J24 will maintain consistency. The provision of gantries at required spacings

will also allow future implementation of VMSL if desired by the Highways Agency.

10.11 The Scheme does not propose to provide GMLS on the southbound approach to J24A as

this is not provided at present, and there is no requirement under IAN149/11 for it to be

provided.

10.12 The following summarises the proposed signalling on the M1 southbound as a result of

the Scheme:




Signal

type Location

Meets

requirements

of IAN149/11

Reasoning Departure

required

Strategic

VMS

300m in advance of

Primary DS for J24A Yes None

Strategic

VMS

200m in advance of

Secondary DS for J24A Yes None

None

At ⅔ mile in advance

of M1 SB J24 exit

datum point

No

Due to J24A

diverge (as

existing)

Yes, departure

from standard is

required, see

departure EMG15.

None

At ⅓ mile in advance

of M1 SB J24 exit

datum point

No

Due to J24A

diverge (as

existing)

Yes, departure

from standard is

required, see

departure EMG15.

GMLS +

VMS

400m (¼ mile) in

advance of M1 SB J24

exit datum point

No as should be

515m – 590m

for ⅓ mile

secondary ADS

Co-located

with

confirmatory

direction sign

for J24A

diverge

Yes, departure

from standard is

required, see

departure EMG14.

GMLS (no

VMS)

50m downstream if

exit datum point No

Due to

proximity of

upstream

bridge and

overhead

power lines

Yes, departure

from standard is

required, see

departure EMG16.

GMLS +

VMS

50m downstream of

diverge nose tip Yes None

GMLS +

VMS

~225m downstream of

merge nose tip Yes None

Strategic

VMS

(existing)

M1 SB intra junction

J24 (but is related to

J23A) ~1890m before

J23A diverge exit

datum

Yes None

GMLS +

VMS

(existing)

~80m beyond J24

merge / ~1120m

before J23A diverge

exit datum

No

Does not

comply with

distance of

300m past

merge entry

datum point

Yes, departure

from standard is

required, see

departure EMG11.

10.13 All existing VMS and GMLS downstream of the above are retained and are unaffected by

the Scheme.

10.14 There is no requirement for an intra-junction J24 GMLS as the distance between the new

J24A merge GMLS and existing J24 merge GMLS is ~1km.




10.15 In addition to the above, entry slip road control signals (MS1) are proposed in the verges

at the start of the proposed J24A merge slip road. The existing entry slip road control

signals at the J24 SB merge will be retained.

Relevant standards for signage

10.16 The signage on the M1 southbound is affected by the relocation of the J24 SB diverge slip

road northwards towards J24A. As noted in Chapter 2 above, the minimum spacing of

the successive diverges complies with TD22/06 but the signage needs to be reviewed

against IAN149.

10.17 TD18/85 gives the criteria for where gantry mounted directional signage should be used.

Gantries are currently used on the approach to J24 but not J24A. TD18/85 is not

amended by IAN149/11 for existing motorways.

10.18 TD18/85 chapter 5 gives the criteria that should be met before using gantry mounted

signage. The most relevant criteria in the case of J24A, J24 and J23A is the use of

gantries to alleviate possible dangerous situations (para 5.2), and para 5.2.2 states that

one of these criteria is “Where a series of junctions are (an average of) less than 3 km

apart measured between centres of junctions”. The spacing between diverges on this

section of the M1 southbound is:

J25 to J24A: ~7km

J24A to J24 (existing): 1.2km

J24A to J24 (as a result of the Scheme): 0.62km

J24 to J23A (existing): 2.6km

J24 to J23A (as a result of the Scheme): 3.18km

10.19 As can be seen from the above, the spacing of the diverges for J24 and J23A from the

upstream diverge are an average of 1.9km; it is thus reasonable that the existing

signage uses gantries for J24 and J23A.

10.20 TD22/06 states that “A full sequence of gantry direction signing is essential for a Ghost

Island diverge layout.” Therefore where ghost island diverges are used gantries must be

provided. This means that gantries are required for J23A irrespective of the criteria in

TD18/85.

Proposed signage

10.21 Based on the criteria in TD18/85, it is considered appropriate that gantries are used for

the J24 diverge as present. However, as the J24A diverge is unaffected by the Scheme,

and it is a reasonable distance from J25, gantry signage is not proposed for this diverge.

10.22 Due to the spacing of the diverges for J24A and J24 the signage needs to be considered

together.

10.23 Use of gantry signage for the J24 diverge would be consistent with the strategy for

gantry mounted lane signals as noted above.

10.24 The table below summarises the sequence of primary signage for the M1 southbound

approaches to both M1 J24A and J24. The signage proposals are shown on drawing

NTH/209/SK67.

10.25 It is noted that IAN149/11 does not cater for this kind of situation as it states that

primary and secondary signs must only be provided at 1 mile and ½ mile, or 2/3 mile

and 1/3 mile, and that a departure is required for any other combination or variation.

This is consistent with TD22/06 para 5.37.




Distance in

advance of

J24A diverge

exit datum

point

Distance in

advance of

J24 diverge

exit datum

point

Sign type Sign complies

with TSRGD Departure required

1 mile 1⅓ mile

Verge

mounted

double

diverge sign

Yes

Yes, departure from

standard is required due to sign showing 1⅓ mile for J24

exit, see departure EMG14.

½ mile ¾ mile

Verge

mounted

double

diverge sign

Yes

Yes, departure from

standard is required due to

sign showing ¾ mile for J24

exit, see departure EMG14.

Final direction

sign ⅓ mile

Verge

mounted

double

diverge sign

Yes

Yes, departure from

standard is required due to sign at ⅓ mile being located

at 614m from exit datum

point, see departures EMG14

and EMG23.

Confirmatory

direction sign

¼ mile located

400m in

advance of M1

SB J24 exit

datum point

Gantry

No (due to

stacking of

destinations and

use of ¼ mile,

but is in

accordance with

current thinking)

Yes, departure from


sign at ¼ mile J24 exit in

addition to upstream ⅓ mile

sign, see departure EMG14.

n/a Final direction

sign Gantry Yes

Yes, departure from


location of sign being 50m

downstream of exit datum

point, see departure EMG16

(the same departure as

noted above for the GMLS)

n/a Confirmatory

direction sign Gantry

No (due to use

of lane arrows,

but is in

accordance with

current thinking)

None

10.26 Downstream of the above, the existing gantry signage for J23A is unaffected by the

Scheme.

10.27 Other signage (e.g. to the MSA and to tourist and local destinations) is not considered in

the above but will be reviewed at detailed design stage. Verge mounted signs will be

used for other signage.

10.28 It is noted that the existing signage on the approach to J24A has rotating prisms that

allow an alternative message to be displayed. Following consultation with both the

TechMAC and Area 7 MAC, no one is aware of what the alternative message is and this

feature is not currently used. It is therefore not proposed to replicate this feature on any

replacement signage.




A50 Eastbound

10.29 The A50 eastbound approach to J24A currently has gantry mounted signage co-located

with GMLS + VMS at 600m upstream of the exit datum point for the lane drop diverge of

the A50EB to M1 NB interchange link. It has a second co-located gantry signage & GMLS

+ VMS at as a confirmatory gantry for this diverge. It does not have any signage at the

exit datum point which is an existing departure under TD22/06 para 5.37. (IAN 149/11

does not apply as the A50 is an all-purpose trunk road). However, this departure is not

affected by the Scheme and so a new departure is not sought.

10.30 It is understood that the GMLS on the A50 eastbound approach is linked to the signalling

on the M1 northbound, and an advisory speed limit is displayed above all lanes on the

A50 if there is an issue on the M1 northbound, not just over the lane that will become a

lane drop.

10.31 It is not proposed to amend the locations of the gantries on the A50 eastbound but, as a

result of the Scheme, it may be beneficial to link the lane signalling over lanes 2 and 3 of

the A50 to the M1 southbound signalling. This will be considered during detailed design.

10.32 The signage over lanes 2 and 3 on the existing confirmatory gantry will be amended to

show the downstream fork junction for the split of the A50 EB to M1 SB interchange link

from the A50 EB to M1 J24 interchange link. This is shown on drawing NTH/209/SK67.

This existing gantry is located ½ mile upstream of the fork so the location would comply

with TD22/06 para 5.37.

10.33 Signage on the A50 EB to M1 SB interchange link downstream of the confirmatory gantry

will be verge mounted as there is no requirement for gantries in this location under

TD18/85. However, during detailed design use of duplicated offside lane signage will be

considered to ensure that drivers are fully aware of the downstream fork.




11.0 SUMMARY OF DEPARTURES

11.1 There are many existing departures from geometric standards that are either removed or

altered as part of the Scheme. In addition, various additional departures from geometric

standards are required in order for the scheme to be implemented. With the exception

of the Kegworth Bypass, all proposed departures from geometric standards have detailed

justifications, drawings and risk assessments provided in the respective application form.

11.2 A summary of existing departures within the extents of the Scheme, and how they are

affected by the Scheme, is given below. Note that in some locations, such as at existing

junctions, there may be several existing geometric departures.

Road / direction Standard Departure Affected by Scheme?

A50 EB approach to

J24A TD46/05

No gantry signals are provided

at the exit datum point Unaffected by Scheme

A50 EB diverge at

J24A TD22/06

Near straight not provided

downstream of diverge as

required by TD22/06

Unaffected by Scheme

A50 between J24 &

J24A TD27/05

Cross section does not conform

to D2AP

A50 SB removed. A50 NB

retained as interchange link,

see departure EMG12.

A50 / Church Street

junction TD42/95

Layout does not meet various

requirements of TD42/95

Junction removed as part

of the scheme.

A50 / Church Street

junction TD9/93

Desirable minimum SSD not

provided on immediate approach

(DAS ID 39965 partly deals)


of the scheme.

A50 / Main Street

junction TD9/93





of the scheme.

A50 NB exit from

M1 J24 roundabout TD9/93

Combination of relaxations to

SSD and radius not permitted

Design speed changed to

85kph as part of the scheme

but there is still a

requirement for a departure

due to combination of

relaxations, see departure

EMG13.

A50 / Hilton Hotel

access TD42/95

Layout does not meet various

requirements of TD42/95

Access removed as part of

the scheme.

A50 / Hilton Hotel

access TD9/93





the scheme.

A50 / Farm access TD9/93





the scheme.





A50 EB approach to

J24A TD46/05



A50 EB diverge at

J24A TD22/06



required by TD22/06


A50 SB approach to

J24 TD50/04

Visibility to signals is less than

desirable minimum SSD

Approach removed as part

of the scheme.

A50 WB after J24A

roundabout past HV

pylon

TD27/05 Cross section does not conform

to D2AP

Existing cross section

retained but road should be

IL2A cross section, see

departure EMG3.

A453 NB south of

J24 TA69/07

Lay-by sited within 3.75Vm of

the roundabout

Lay-by removed as part of

the scheme.

A453 SB south of

J24 TA69/07


the roundabout



and it complies.

A453 SB south of

J24 TD9/93

Crest K value below desirable

minimum on approach to Ashby

Road junction (approx KF 65

which should be 182)

Junction amended, design

speed changed to 85kph

and visibility improved as

part of the scheme but there

is still a requirement for 1

step below des min SSD, see

departure EMG9.

A453 NB approach

to J24

TD16/07 &

TD9/93





and it complies.

A6 NB approach to

J24

TD50/04 &

TD9/93


provided on immediate approach Unaffected by Scheme

A453 SWB

approach to J24 TD9/93



(DAS ID 47598)


A453 NEB exit from

J24 TD9/93



(DAS ID 47609)


M1 SB J24A diverge

slip road TD27/05


to IL2A where it crosses over

the M1

Cross section revised merge

but will not be compliant, see

departure EMG2.

M1 SB J24 merge

slip road TD27/05


to MG2C

For some of the lentgth the

cross section amended to

MG1A as part of the Scheme.

However, existing cross

section will remain where

unaffected by the Scheme.





A50 EB approach to

J24A TD46/05



A50 EB diverge at

J24A TD22/06



required by TD22/06


M1 SB J24 merge TD22/06 Merge layout F is not as per

standards Merge amended to layout B

M1 SB J24 merge TD27/05 Cross section does include full

width hardshoulder

Cross section for revised

merge will not include

hardshoulder, see departure

EMG10.

A453 NB north of

J23A roundabout TA69/07


the J23A roundabout Unaffected by Scheme

A453 SB north of

J23A roundabout TA69/07


the J23A roundabout Unaffected by Scheme

M1 SB north of J24

diverge IAN149/11

Control signals not provided at

Primary DS

Signage amended but

departure still required, see

departure EMG15.

M1 SB north of J24

diverge IAN149/11

Secondary (½ mile) DS outwith

location requirements for gantry

sign

Gantry sign removed as

part of Scheme

M1 SB north of J24

diverge IAN149/11

Final DS outwith location

requirements for gantry sign

Sign relocated but is still

outwith location

requirements, see

departure EMG16.

M1 SB at J24

diverge IAN149/11

Confirmatory DS outwith

location requirements for gantry

sign

Gantry sign removed as

part of Scheme

M1 SB at J24 merge IAN149/11 Intra-junction control signals not

located near mid-point

Control signals relocated

as part of Scheme

M1 SB south of J24

merge IAN149/11

Lane control signals outwith

location requirements

Sign retained, merge layout

amended but is still outwith

location requirements, see

departure EMG11.

11.3 The following is a summary of the departures from geometric standards that are required

in order for the Scheme to be constructed:

Road / direction

Standard Departure Departure reference

Approving authority

Current Status

A50EB – M1SB IL

TD27/05 Cross section does not comply with IL2C

EMG1 HA Approved with comments




Road /

direction Standard Departure

Departure

reference

Approving

authority Current Status

M1SB –

A50WB IL TD27/05

Cross section does not comply with

IL2A EMG2 HA

Approved with

comments

M1SB – A50WB IL

TD27/05 Cross section does not comply with IL2A


A50EB – M1SB

IL TD9/93

Combined relaxation of 2 steps below des min SSD and 3 steps below des min radius

EMG4 HA Submitted for

review

A50EB – M1SB IL

TD22/06 Cross section IL1A provided in lieu of IL2A

EMG5 HA Approved

M1SB – J24 IL TD22/06 Weaving distance less than 1km EMG6 HA Approved with

comments

M1SB at J24 diverge

IAN149/11

TD27/05 Discontinuous hardshoulder EMG7 HA

Approved with comments

M1SB through J24

IAN149/11 Discontinuous hardshoulder EMG8 HA Submitted for review

A453 SB south of J24

TD9/93 1 step below des min Crest K value on immediate approach to junction

EMG9 HA Submitted for review

M1SB at J24 merge

IAN149/11

TD27/05 Discontinuous hardshoulder EMG10 HA

Approved with comments

M1SB south of J24 merge

IAN149/11

GMLS does not comply with distance

of 300m past merge entry datum point


M1J24 – A50WB IL

TD27/05 Cross section does not comply with IL2C


M1J24 –

A50WB IL TD9/93

Combined relaxation of 1 step below des min SSD and 1-2 steps below des min radius

EMG13 HA Approved

M1SB north of J24 diverge

IAN149/11

Spacing of signage on approach to

Junction 24 diverge does not comply with standard rules for 1 mile (2/3 mile) primary sign, ½ mile (1/3 mile) secondary sign.


M1SB north of

J24 diverge IAN149/11

Control signals not co-located with primary and secondary direction signs

EMG15 HA Approved with

comments

M1SB north of J24 diverge

IAN149/11 Final DS outwith location requirements for gantry sign


A6 Kegworth

Bypass TD9/93

1 step below des min Crest K value

on immediate approach to junction EMG17 LCC

Submitted for

review

A6 Kegworth

Bypass TD9/93

1 step below abs min Sag K value


Submitted for

review

A6 Kegworth

Bypass TD9/93

1 step below abs min Sag K value


Submitted for

review




Road /

direction Standard Departure

Departure

reference

Approving

authority Current Status

Local access

road approach to J24 roundabout

TD16/07

TD9/93

Desirable minimum SSD not provided on immediate approach

EMG22 LCC Submitted for review

M1SB north of J24A diverge

IAN149/11 1/3 mile DS outwith location requirements for J24 diverge


11.4 Note that departures EMG20 and EMG21 relate to street lighting on the A453 between

J24 and J23A. As these are not departures from geometric standards they do not feature

in this report.




12.0 REFERENCES

12.1 The following design standards are referred to in this report:

Reference Title

IAN149/11 Existing Motorway Minimum Requirements

http://www.dft.gov.uk/ha/standards/ians/pdfs/ian149.pdf

TA46/97 Traffic Flow Ranges for Use in the Assessment of New Rural Roads

http://www.dft.gov.uk/ha/standards/dmrb/vol5/section1/ta4697.pdf

TA91/05 Provision for Non-motorised Users


TD9/93 Highway Link Design

http://www.dft.gov.uk/ha/standards/dmrb/vol6/section1/td993.pdf

TD16/07 Geometric Design of Roundabouts


TD18/85

Criteria for the Use of Gantries for Traffic Signs and Matrix Traffic

Signals on Trunk Roads and Trunk Road Motorways


TD22/06 Layout of Grade Separated Junctions


TD27/05 Cross-Sections and Headrooms


TD41/95 Vehicular Access to All-Purpose Trunk Roads


TD42/95 Geometric Design of Major/Minor Priority Junctions


TD50/04

The Geometric Layout of Signal-Controlled Junctions and Signalised

Roundabouts


TD51/03

Segregated Left Turn Lanes and Subsidiary Deflection Islands at

Roundabouts


TD69/07 The Location and Layout of Lay-bys and Rest Areas


http://www.dft.gov.uk/ha/standards/ians/pdfs/ian149.pdf
















Figures 3.1 to 3.4 – TD22/06 Merge and Diverge Assessments

EMG SRFI: Figure 3.1 J24A SB merge2016 Mitigation Case: AM peak

2016 Mitigation Case: PM peak

EMG SRFI: Figure 3.2 J24 SB diverge 2016 Mitigation Case: AM peak


EMG SRFI: Figure 3.3 SB merge within interchange2016 Mitigation Case: AM peak


EMG SRFI: Figure 3.4 J24 SB merge2016 Mitigation Case: AM peak





Page 71

Appendix A – Scheme layout drawings

The following scheme layout drawings are provided:

Drawing No. Title

NTH/209/100-01 General arrangement – J24A and J24

NTH/209/100-02 General Arrangement and Long sections – A453 Development

Access

NTH/209/100-03 General arrangement – A6 Kegworth Bypass




Page 72

Appendix B – Long section drawings

The following long section drawings are provided:

Drawing No. Title

NTH/209/101-01 Long sections – J24A and J24

NTH/209/100-02 General Arrangement and Long sections – A453 Development

Access

NTH/209/101-03 Long sections – A6 Kegworth Bypass




Page 73

Appendix C – Cross section drawings

The following cross section drawings are provided:

Drawing No. Title

NTH/209/102-01

NTH/209/102-05 Cross sections – J24A and J24

NTH/209/102-02 Cross sections – A453 Development Access

NTH/209/102-03 Cross sections – A6 Kegworth Bypass

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