POWER BUILDING TO THE OVERHEAD PEOPLE LINES · SC-48 PLATFORMS AND FOUNDATIONS Vibrating Concrete...
Transcript of POWER BUILDING TO THE OVERHEAD PEOPLE LINES · SC-48 PLATFORMS AND FOUNDATIONS Vibrating Concrete...
POWER
TO THE
PEOPLE
BUILDING
OVERHEAD
LINES
SAROOJ CONSTRUCTION COMPANY
Quarterly Newsletter Volume 4, Issue 1 Jan - Feb - Mar 2012
IN THIS ISSUE: SC– 48 PROJECT OVERVIEW, PROJECT BACKGROUND, PROJECT SCOPE, ROUTE AND TOWERS,
ACCESS ROADS, SOIL INVESTIGATION, PLATFORMS AND FOUNDATIONS , STUB SETTING, TOWER
ERECTION, TEST FOUNDATIONS, COMPANY NEWS, PROJECT VISUALS.
Message From the General Manager...
Dear Colleagues,
Sarooj enjoys getting more and more involved
in challenging projects considering their site
conditions , their remoteness from main base, their
access through several boarder checkpoints, and
their location in urban congested areas or in the
desert wilderness.
Among these projects, are those concerned with
the construction of electrical overhead lines. To
satisfy the increasing demand of electricity in
Oman (around 11% every year), new lines as well
as extensions to the national grid have been built.
These are generally high voltage lines (132KV, 220
KV, and soon 400 KV). Furthermore, the sprawling
of cities up to the mountain toes pushed away the
route of these overhead lines towards inaccessible
areas where development is unlikely to take place.
Sarooj has acquired vast experience in the
construction of these tower lines. The 132 KV line
from Manahto Rusayl, the 132 KV line from Nizwa
to Ibri, the 220 KV line from Sohar to Seeb are
examples of these projects. The latest project is
being highlighted in this newsletter.
Notwithstanding the passion of this type of works,
Sarooj should always prepare meticulous planning
and implement rigorous management of hazards
inherent to construction activities on these projects
and especially when commuting between base and
site.
This acquired experience by Sarooj may be offered
to its valuable clients to add value engineering that
gives good returns. However, this should never
be envisaged if safety, quality, and integrity are
jeopardized.
Sarooj shall continue teaming with selected
partners to build such projects
Jad Karam
General Manager
CONTENTS
SC-48 Project Overview Pg 3
SC-48 Project Background Pg 4
SC-48 Project Scope Pg 5
SC-48 Route and Towers Pg 6
SC-48 Access Roads Pg 7
SC-48 Soil Investigation Pg 8
SC-48 Platforms and Foundations Pg 9
SC-48 Stub Setting Pg 11
SC-48 Tower Erection Pg 12
SC-48 Test Foundations Pg 13
Company News Pg 14
Project Visuals Pg 15
SC-48 BUIlDING OVERHEAD lINES
The Project:
Diversion of Overhead lines
The Client:
The Palace Office-Muscat
The Project Manager:
V.C. Pandian
The Engineer:
Mott McDonald
The Main Contractor:
GAM and Partners with Sarooj
location:
Muscat
Contract Duration:
12 months
Project Value:
8.5 Million Dollars
OVERVIEW
4
PREamblE
It was decided to build a government complex on an elevated plateau in Muscat. Three 132KV overhead lines
crossed the plot and had to be diverted away from the project boundaries towards high mountains and deep
wadis. GAM of Iran, another company from the Sarooj group, and Sarooj won the contract to build 3x 132KV new
lines extending about 7km each and making thus a total of 21kms of lines carried by 60 towers.
SC–48 PROJECT BACKGROUND
Access Roads Along The Route
Overlooking Qurum Area
Taking a Rest
The Route
5
All Anchors in Place
Fixing and Grounting Anchors
ROuTE & TOWERS
Usually a thorough survey should be carried out
in the mountains to be able determine a corridor
through which the route of the overhead line would
go. The land surveyor has to be good mountain
trekker as well as an accurate technician! A first attempt is made and the line is marked on the
ground. It is very seldom that the final route is established from the first attempt as a clearance has to be kept eventually between the lines and the
surrounding mountains. Refinements are made to
SC-48 PROJECT SCOPE
Hand Drilling for Rock Anchors
Excavation for Footings
satisfy this condition followed by adjustments on
site. Preliminary approval of the route is obtained
and at this stage the construction of temporary
access roads may start.
For each tower the centers of the four legs are
marked and a final site inspection takes places to establish, on the ground, whether certain locations
have to move slightly to accommodate the four
legs.
A final survey is carried out around the location to work out the final levels of the four legs. It is after this last phase that the final coordinates are determined. The shape of the tower and its full
design can be completed except for the type of
foundation. This will depend on the type of soil
encountered.
6
SC–48 ACCESS ROADS AND SOIl INVESTIGATION
aCCESS ROadS
For the safe movement of personnel, equipment
and vehicles, adequate access roads have to be
built and maintained. These roads would also
serve after construction for maintenance and
verification of the integrity of the line at all times. A critical factor is the gradient which should not be
greater than 15% to allow vehicles and equipment
to climp up and down safely. A main service road
would typically be built with links to every location.
Dust generated is controlled by spraying regularly
water on their surface.
SOIl INVESTIgaTION
Once the roads are built a soil investigation
campaign is started to establish what type of soil is
encountered in every location and a series of tests
is run to determine the various soil properties:
bearing capacity, electric resistivity, salts content…
Depending on these characteristics, the type of
foundation is established: pad and chimney type
or rock anchor type…
Fixing Steel Reinforcement
Checking
Concrete Pad to Receive Stub
Stub Setting
7
SC-48 PlATFORMS AND FOUNDATIONS
Vibrating Concrete
Concreting Against Natural Soil
PlaTfORmS
When the difference in level of the natural ground
between the high legs and the lower legs is not
great, the area around the tower center is levelled
and the top of the four legs foundations becomes
common.
If the difference is tangible, two strips are created
to provide access to machines and materials. The
four legs in this case would not be on the same
level. Different stubs will have to be provided.
Haunching Stubd End
Copper Earthing Strip
Pad- aNd- ChImNEy fOuNdaTIONS
Where the ground is not rocky or consisting of
very weathered rock, the foundations are of the
pad- and chimney type which spread the load
when compressed and resist to lifting by their
weight and the weight of the fill above them. The footings are backfilled in compacted layers.
ROCK aNChOR- fOuNdaTION
Where solid monolithic rock is encountered the
rock anchor type foundation is preferred. Holes
are drilled into the rock. Anchor rods inserted
and special grout poured into them. The rods
extensions are linked to the steel reinforcing bars
of the concrete footing forming thus a structure that
can take compression and relies on the anchors to
resist uplift.
8
SC-48 STUB SETTING
Backfilling Completed
Chimneys
STub SETTINg
These stubs should be procured and delivered at an early stage so
that the casting of the foundations may take place. Their lengths
are generally a multiple of a certain basic length l and they may
be 2L, 3L or even 4L. The tubs have to be fixed inclined to a given degree. The tolerance in their position is small and therefore they
have to be set firmly and accurately. To avoid the cumbersome templates, the stubs are held in position by two telescoping props
fixed to the ground hinges on one side and other set of hinges on the stub. This allows flexibility in adjustments.
Vibrating Concrete
Backfilling around Chimney
9
Harnessed Steel Erectors
Tower
Tower Erection
Bottom Tower
SC-48 TOWER ERECTION AND TEST FOUNDATIONS
TOWER ERECTION
Usually when on a flat terrain, the towers would be assembled in 2- 3
parts and lifted into position using
cranes. This is an easier and safer
manner. However, when working on
steep slopes in the mountains, the
towers are erected piece by piece
by steel fixers well trained and well harnessed to prevent incidents.
TEST fOuNdaTIONS
In order to verify the design
calculations, test foundations are
constructed in the vicinity and pulled
out until failure. These control tests
are carried out whenever the nature
of the ground changes.
10
SC-48 PROJECT VISUAlS
11
SC-48 PROJECT OVERVIEW
general Project features
length of Project 21km in Mountains
Number of Towers 60 Nos
Type of Overhead line 132KV
Access Roads 18 KM
12
ONSITE WORKFORCE
Jad Karamgeneral manager
V.C. PandianProject manager
Chawky g. RamyOperations manager (PmV)
mansoor El akouryConstruction manager
mohammed NazeerSupervisor
13
SAROOJ NEWS
COMPANY NEWS
• Justus Harding joined as Corporate HSE Manager. We wish him success with
everybody’s support as safety is common
responsibility.
• Heinrich Peter Hertl joined as `Earthworks΄ general supervisor and assumed his
assignment on the Musandam Gas Plant
Project (MGP).
• The company acquired the largest excavator manufactured by caterpillar. It is the CAT
385.
• Sarooj participated to the annual European Community Council gala dinner. Sarooj has
three major European strategic partners
namely Majus (UK), Bauer (Germany) and
Colas (France).
• Elie Nammour and Mohammad Naseer Mammoo attended an advance course in MS
Projects as part of their training programme.
• Sarooj, Hanjin, and Lotte of south Korea have agreed to form a joint venture to tender
for the Batinah Expressway- Package 3
• Anthony Helou and Kamran Sami travelled to Singapore representing Sarooj in the
potential Joint Venture between Mitsui,
Hyflux and Sarooj to bid for the al Ghubrah power and desalination plant extension.
• Sarooj came lowest bidder (L1) in the Madha road project tender.
• Sarooj were awarded a contract in Muscat for the rehabilitation of three bridges in the
Capital Area namely wadi Adai, Hamriya,
and Ruwi.
14
SAROOJ NEWS
COMPANY NEWS
15
Sarooj Construction Company LLC ● P.O.Box 1413, Postal Code 112 ● Ruwi, Sultanate of Oman.Telephone: (+968) 24 596001 ● Fax: (+968) 24 596011
www.sarooj.com ● [email protected]
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