Chapter 5 Scheduling Tracking Work

CHAPTER 5

SCHEDULING AND TRACKING WORK IN CONSTRUCTION PROJECT MANAGEMENT

Introduction

Planning & Scheduling

Principles

Techniques

Work breakdown structure

Gantt Chart & S-Curve

Critical Path Method

Successor/ predecessor relationship

Arrow Diagram Method and Precedence Diagram Method

THE INTEGRATION OF TIME & SUSTAINABLE CONSTRUCTION

Our focus!!

Traditional Projects Critical Components (time, cost, & quality); in relation with sustainable construction concept

Introduction

Project planning

Process of identifying all the activities necessary to successfully complete the project.

Provides map to guide where to go and focused on how to get there

Planned in early stage of Project life Cycle or also before site activities start.

Introduction

Importance of planning

Reduce mistake and rework

Avoid wastage

minimize unnecessary in time and cost scheduling

better quality control

Effective project progress control

Effective usage resources

Introduction

Project scheduling

Process of determining the sequential order of the planned activities, assigning realistic durations to each activity and determining the start and finish dates for each activities.

it can be used to manage, coordinate, control and report.

Depending on the sophistication of the user, the schedule can take different forms.

Project Scheduling

Purpose of project scheduling Claim Project time and cost control Allocate project resources more efficiently As a monitoring tool Material delivery at site Storage all material cannot put in the site (confined space) Avoid delay of the work and activity. Minimize the cash flow as min as possible such as order material

stage by stage depend on the work needed. Control human resources and machinery To improve the efficiency

of the operation through the efficient use of resources and cost control.

Project planning is prerequisite to project planning!

Desired results of planning and scheduling Finish the project on time.

Continuous (uninterrupted) flow of work (no delays)

Reduced amount of rework (least amount of changes)

Minimized confusion on misunderstandings.

Increase knowledge of status of project by everyone.

Meaningful and timely reports to management.

You run the project instead the project running you.

Knowledge of scheduled times of key parts of the project.

Knowledge of the distributions of costs of the project

Accountability of people, define responsibility/authority.

Clear understanding of who does what, when & how much.

Integration of all work to ensure a quality project for the owner.

What are the different?

Planning is more difficult to accomplish than scheduling.

The term planning and scheduling are often used synonymously.

Planning is first step to project scheduling.

Tools used for planning and scheduling are different!

Principles of planning and scheduling Begin planning before starting work, rather than after starting

work. Involve people who will actually do the work in the planning

and scheduling process. Includes all aspects of the project: scope, budget, schedule &

quality. Build flexibility into the plan, include allowance for changes and

time for reviews and approvals. Remember the schedule is the plan for doing the work, and it

will never be precisely correct. Keep the plan simple, eliminate irrelevant details that prevent

the plans from being readable. Communicating the plan to all parties; any plan is worthless

unless it is known.

The Collection of Projects Critical Components (should be in equilibrium)

02468

101214161820

COST

RESOURCES

SCOPEQUALITY

TIME

Client Satisfaction

Steps in planning and scheduling

Scope definition

Cost Budgeting Cost Estimating

Activity resource planning

Activity Duration

Estimation

Schedule development

Activity Sequencing

Create WBS

Scope Management

Time & Resource

Management

Cost Management

Steps in planning and scheduling

1. Develop a work breakdown structure (WBS)

2. Prepare a drawing (network diagram)

3. Determine the time, cost and resources required

4. Compute the schedule to determine start, finish and float times

5. Analyze costs and resources for the project

6. Communicate the results of the plan and schedule

Work breakdown structure (WBS)

Identifies the tasks and activities that must be performed.

It divides the project into identifiable parts that can be managed.

Concept of WBS: in order to manage a whole project, one must manage and control each of its parts.

It defines: The work to be performed The need of expertise Assist in selection of project team Establish a base of project scheduling and control


WBS is display as a graphical or outline method that shows the division of work in a multi level system.

In developing WBS, we should consider:

Activities that require time

Activities that require cost

Activities that need to arrange

Activities that need to monitor

Work Breakdown Structure (Graphical)

Construction of one block office building

Start Project Preliminaries

Performance bond

Establish and removal of site

office

Block A

Earthwork

Structure Work

Architecture Work

M&E work

Testing & Commissioning

Project complete

Level 1

Level 2

Level 3

Work Breakdown Structure (Outline) Construction of one

block office building Start Project

Preliminaries

Performance bond

Establish and removal of site office

Block A

Earthwork

Structure Work

Architecture Work

M&E work

Testing and Commissioning

Project complete

Work breakdown structure (WBS) Importance of WBS

Overall program can be explain in summary according to each sub-element divided.

Planning could execute. Cost and budget could estimate more accurately. Time, Cost and Performance of each element could be

monitor from time to time. Objective could be relate directly with the available

resources in the company. Network diagram and control planning could be prepared

in early stages. Responsibilities for each parties involve in every element

could be identify and assign.


Example:

You are the Project Manager for a Construction of Proposed Construction and Completion of a Double Storey Bungalow House And Related Works For Messrs. Dato 'Kamal Jaafar. Develop a preliminary graphical work breakdown structure (up to level 4) for the project given. Your WBS should complete with all works needs in completing a one unit bungalow.

Example (WBS-Graphical Method)

Proposed Construction and Completion of A Double Storey Bungalow House and Related Works for Messrs. Dato 'Kamal Jaafar.

Preliminary works

Performance bond

Progress Report

Building works

Structure

Foundation

Ground level

1st floor level

2nd floor level

Architecture

Wall

Floor

Roof

Fittings

M&E

Wiring

Fittings installation

External works

Sewerage

Road and drainage

Landscape

Level 1

Level 2

Level 3

Level 4

Exercise (Outline Method)

Proposed Construction and Completion of A Double Storey Bungalow House and

Related Works for Messrs. Dato 'Kamal Jaafar.

Techniques for scheduling

Techniques used will vary depending on: Projects size Complexity Duration Personnel Owner requirements

Two general methods commonly used : Bar chart (Gantt chart) Critical path method (CPM/ network analysis

system)

Develop by Henry L.Gantt

Is a graphical time-scale of the schedule, length represent the duration of activity.

Advantages

Easy to interpret

Simplicity & ease of preparation and understanding (Simple graphical).

No theory or complicated calculation involved (Easy for general comprehension).

Time-scaled (the length of the bar representing certain activity is proportional to the duration of that activity.

Appeal to persons who do not have a technical background

Wide spread used in industry

Mostly used in small project

Fairly broad planning and scheduling tools, so they require less revision and updating than more sophisticated systems

Disadvantages

Difficult to update

Very cumbersome as the number of line activities, or bars increases

Does not integrate costs or resources with the schedule

Limited application for detail construction work

Difficult to use it for forecasting the effects that changes in a particular activity will have on the overall schedule

No. Description Month 1 2 3 4 5 6 7 8 9 10

1 Mobilization

2 Foundation Excavation

3 Diversion Stage

4 Foundation Grouting

5 Dam Concrete

6 Install Outlet Gates

7 Install Trash Racks

8 Prestress

9 Radial Gates

10 Spillway Bridge

11 Curtain Grout

12 Dismantle Plant, Clean Up

Original Schedule

Actual progress

Bar chart basically use x-axis only (to depict time). The y-axis is use to show individual activities, to represent a variable across time

(e.g.: man-hours, budget, % complete and so forth.

Bar chart (Gantt Chart)

No. Description Month 1 2 3 4 5 6 7 8 9 10

1 Mobilization

2 Foundation Excavation

3 Diversion Stage

4 Foundation Grouting

5 Dam Concrete

6 Install Outlet Gates

7 Install Trash Racks

8 Prestress

9 Radial Gates

10 Spillway Bridge

11 Curtain Grout

12 Dismantle Plant, Clean Up

Original Schedule

Actual progress

Cu

mu

lati

ve p

rogr

ess

(%)

100

0

Bar chart basically use x-axis only (to depict time). The y-axis is use to show individual activities, to represent a variable across time (e.g.: man-hours,

budget, % complete and so forth. The variables usually shown as a curve superimposed on the bar chart.

Bar chart (Gantt Chart) + S curve

Bar chart (Gantt Chart)

Tutorial No.2: A project consist of five activities that should be

done in a period of time. Try to create a bar chart to ease the project planning and scheduling.

* consider 1 week as 7 days

Activity A : 1 week, starting from 1 Jun 2015 Activity B : 2 week, starting from 8 Jun 2015 Activity C : 3 week, starting from 15 Jun 2015 Activity D : 2 week, starting from 22 Jun 2015 Activity E : 2 week, starting from 29 Jun 2015

Bar chart (Gantt Chart)-Example 1

Step 1: identify start date and finish date for each activity Activity A : 1 week, starting from 1 Jun 2014 (1/6-7/6)

Activity B : 2 week, starting from 8 Jun 2014 (8/6-21/6)

Activity C : 3 week, starting from 15 Jun 2014 (15/6-5/7)

Activity D : 2 week, starting from 22 Jun 2014 (22/6-5/7)

Activity E : 2 week, starting from 29 Jun 2014 (29/6-12/7)


Step 2: Draw outline of bar chart

Activity Duration (week)

Week 1 Week 2 Week 3 Week 4 Week 5 Week 6

1/6 8/6 15/6 22/6 29/6 6/7

Act. A 1

Act. B 2

Act. C 3

Act. D 2

Act. E 2


Activity Duration (week)

Week 1 Week 2 Week 3 Week 4 Week 5 Week 6

1/6 8/6 15/6 22/6 29/6 6/7

Act. A 1

Act. B 2

Act. C 3

Act. D 2

Act. E 2

Step 3: Draw the activity bars

Activity A : 1 week, starting from 1 Jun 2014 (1/6-7/6) Activity B : 2 week, starting from 8 Jun 2014 (8/6-21/6) Activity C : 3 week, starting from 15 Jun 2014 (15/6-5/7) Activity D : 2 week, starting from 22 Jun 2014 (22/6-5/7) Activity E : 2 week, starting from 29 Jun 2014 (29/6-12/7)


Num Activity Duration (days)

Start Date Cost (RM)

Resources/ day

(person)

Work progress

percentage (%)

1 Activity A 3 4/5/2014 1,400.00 2 12

2 Activity B 5 7/5/2014 2,700.00 3 30

3 Activity C 7 10/5/2014 3,500.00 2 21

4 Activity D 5 15/5/2014 6,000.00 4 10

5 Activity E 4 17/5/2014 4,700.00 4 12

6 Activity F 6 19/5/2014 12,600.00 5 15

30,900.00 100


Step 1: identify start date and finish date for each activity Activity A : 3 days, starting from 4 May 2014 (4/5-6/5)

Activity B : 5 days, starting from 7 May 2014 (7/5-11/5)

Activity C : 7 days, starting from 10 May 2014 (10/5-16/5)

Activity D : 5 days, starting from 15 May 2014 (15/5-19/5)

Activity E : 4 days, starting from 17 May 2014 (17/5-20/5)

Activity F : 6 days, starting from 19 May 2014 (19/5-24/5)


Step 2: Draw outline of bar chart

Activity Duration (days) 4

/5

5/5

6/5

7/5

8/5

9/5

10

/5

11

/5

12

/5

13

/5

14

/5

15

/5

16

/5

17

/5

18

/5

19

/5

20

/5

21

/5

22

/5

23

/5

24

/5

Act. A 3

Act. B 5

Act. C 7

Act. D 5

Act. E 4

Act. F 6


Step 3: Draw the activity bars

Activity Duration (days) 4

/5

5/5

6/5

7/5

8/5

9/5

10/5

11/5

12/5

13/5

14/5

15/5

16/5

17/5

18/5

19/5

20/5

21/5

22/5

23/5

24/5

Act. A 3

Act. B 5

Act. C 7

Act. D 5

Act. E 4

Act. F 6

Activity A : (4/5-6/5) Activity B : (7/5-11/5) Activity C : (10/5-16/5) Activity D : (15/5-19/5) Activity E : (17/5-20/5) Activity F : (19/5-24/5)

An S-curve is defined as:

"A display of cumulative costs, labor hours or other quantities plotted against time. The name derives from the S-like shape of the curve, flatter at the beginning and end and steeper in the middle, which is typical of most projects. The beginning represents a slow, deliberate but accelerating start, while the end represents a deceleration as the work runs out."

S-Curve

Type of S-Curve

Physical S-Curve

Financial S-Curve

Both S-curve can be in Baseline (planned) or actual S-curve

S-Curve (Example) Num Activity Duration

(days) Start Date Cost (RM)

Resources/

day (person)

Work progress

percentage (%)

1 Activity A 3 4/5/2014 1,400.00 2 12

2 Activity B 5 7/5/2014 2,700.00 3 30

3 Activity C 7 10/5/2014 3,500.00 2 21

4 Activity D 5 15/5/2014 6,000.00 4 10

5 Activity E 4 17/5/2014 4,700.00 4 12

6 Activity F 6 19/5/2014 12,600.00 5 15

30,900.00 100

Based on bar chart in Example 2, construct S-curve (daily basis) for this project: 1. Financial S-Curve 2. Physical S-curve (resources vs time & work vs time)

Financial S-Curve

Financial S-Curve

Activity Duration (days)

Cost (RM)

Cost/day (RM) 4/

5

5/5

6/5

7/5

8/5

9/5

10

/5

11

/5

12

/5

13

/5

14

/5

15

/5

16

/5

17

/5

18

/5

19

/5

20

/5

21

/5

22

/5

23

/5

24

/5

Act. A 3 1,400

Act. B 5 2,700

Act. C 7 3,500

Act. D 5 6,000

Act. E 4 4,700

Act. F 6 12,600

Cost/day

Cumulative cost/day

STEP 1: DRAW BAR CHART (from Example 2), include Cost of each activity

Financial S-Curve


Cost (RM)

Cost/day (RM) 4/

5

5/5

6/5

7/5

8/5

9/5

10

/5

11

/5

12

/5

13

/5

14

/5

15

/5

16

/5

17

/5

18

/5

19

/5

20

/5

21

/5

22

/5

23

/5

24

/5

Act. A 3 1,400

Act. B 5 2,700

Act. C 7 3,500

Act. D 5 6,000

Act. E 4 4,700

Act. F 6 12,600

Cost/day

Cumulative cost/day

=1,400/3

=2,700/5

=3,500/7

=6,000/5

=4,700/4

=12,600/6

467

540

500

1200

1175

2100

STEP 2: Calculate COST/ DAY = Cost / duration

Financial S-Curve


Cost (RM)

Cost/day (RM) 4/

5

5/5

6/5

7/5

8/5

9/5

10

/5

11

/5

12

/5

13

/5

14

/5

15

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16

/5

17

/5

18

/5

19

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20

/5

21

/5

22

/5

23

/5

24

/5

Act. A 3 1,400

Act. B 5 2,700

Act. C 7 3,500

Act. D 5 6,000

Act. E 4 4,700

Act. F 6 12,600

Cost/day

Cumulative cost/day

467

540

500

1200

1175

2100

STEP 2: Calculate COST/ DAY = Cost / duration


Cost (RM)

Cost/day (RM) 4/

5

5/5

6/5

7/5

8/5

9/5

10

/5

11

/5

12

/5

13

/5

14

/5

15

/5

16

/5

17

/5

18

/5

19

/5

20

/5

21

/5

22

/5

23

/5

24

/5

Act. A 3 1,400

Act. B 5 2,700

Act. C 7 3,500

Act. D 5 6,000

Act. E 4 4,700

Act. F 6 12,600

Cost/day

Cumulative cost/day

Financial S-Curve

467

540

500

1200

1175

2100

STEP 3: Calculate the TOTAL COST of each DAY

46

7

10

40

46

7

46

7

10

40

5

00

5

00

5

00

1

70

0

17

00

2

37

5

23

75

4

47

5

32

75

2

10

0

21

00

2

10

0

21

00

54

0

54

0

54

0

540 +500


Cost (RM)

Cost/day (RM) 4/

5

5/5

6/5

7/5

8/5

9/5

10

/5

11

/5

12

/5

13

/5

14

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15

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16

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17

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18

/5

19

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20

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21

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22

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23

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24

/5

Act. A 3 1,400

Act. B 5 2,700

Act. C 7 3,500

Act. D 5 6,000

Act. E 4 4,700

Act. F 6 12,600

Cost/day

Cumulative cost/day

Financial S-Curve

467

540

500

1200

1175

2100

STEP 4: Calculate the CUMULATIVE COST of each DAY

46

7

10

40

46

7

46

7

10

40

5

00

5

00

5

00

1

70

0

17

00

2

37

5

23

75

4

47

5

32

75

2

10

0

21

00

2

10

0

21

00

54

0

54

0

54

0

46

7

93

4

1941

24

81

3021

40

61

5101

56

01

6101

66

01

8301

10

01

1237

6

1475

1

1922

6

2250

1

2460

1

2670

1

2880

1

3090

1

Cumulative cost (previous) + current cost/day = 467 + 467

Cumulative cost (previous) + current cost/day = 934 + 467

10

41

Financial S-Curve


Cost (RM)

Cost/da y (RM) 4/

5

5/5

6/5

7/5

8/5

9/5

10

/5

11

/5

12

/5

13

/5

14

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15

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16

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17

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18

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19

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20

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21

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22

/5

23

/5

24

/5

Act. A 3 1,400

Act. B 5 2,700

Act. C 7 3,500

Act. D 5 6,000

Act. E 4 4,700

Act. F 6 12,600

Cost/day

Cumulative cost/day

467

540

500

1200

1175

2100

30900

25750

20600

15450

10300

5150

0

46

7

10

40

46

7

46

7

54

0

54

0

54

0

10

40

5

00

5

00

5

00

1

70

0

17

00

2

37

5

23

75

4

47

5

32

75

2

10

0

21

00

2

10

0

21

00

46

7

93

4

10

41

1

94

1

24

81

3

02

1

40

61

5

10

1

56

01

6

10

1

66

01

8

30

1

10

00

1

12

37

6

14

75

1

19

22

6

22

50

1

24

60

1

26

70

1

28

80

1

30

90

1

STEP 5: Plot graph base on cumulative cost

Start from 0

Total cumulative cost

Get the medium (30900 /2)

Start from 0

467 934 1041

Financial S-Curve


Cost (RM)

Cost/da y (RM) 4/

5

5/5

6/5

7/5

8/5

9/5

10

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11

/5

12

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13

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14

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17

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18

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19

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20

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21

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22

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23

/5

24

/5

Act. A 3 1,400

Act. B 5 2,700

Act. C 7 3,500

Act. D 5 6,000

Act. E 4 4,700

Act. F 6 12,600

Cost/day

Cumulative cost/day

467

540

500

1200

1175

2100

30900

25750

20600

15450

10300

5150

0

46

7

10

40

46

7

46

7

54

0

54

0

54

0

10

40

5

00

5

00

5

00

1

70

0

17

00

2

37

5

23

75

4

47

5

32

75

2

10

0

21

00

2

10

0

21

00

46

7

93

4

10

41

1

94

1

24

81

3

02

1

40

61

5

10

1

56

01

6

10

1

66

01

8

30

1

10

00

1

12

37

6

14

75

1

19

22

6

22

50

1

24

60

1

26

70

1

28

80

1

30

90

1

STEP 5: Plot graph base on cumulative cost

Physical S-Curve (resources VS time)



Resources/ day

(person)

Work progress

percentage (%)

1 Activity A 3 4/5/2014 1,400.00 2 12

2 Activity B 5 7/5/2014 2,700.00 3 30

3 Activity C 7 10/5/2014 3,500.00 2 21

4 Activity D 5 15/5/2014 6,000.00 4 10

5 Activity E 4 17/5/2014 4,700.00 4 12

6 Activity F 6 19/5/2014 12,600.00 5 15

30,900.00 100



Resource/ day

4/5

5/5

6/5

7/5

8/5

9/5

10

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11/5

12

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21

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22

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23

/5

24

/5

Act. A 3 2

Act. B 5 3

Act. C 7 2

Act. D 5 4

Act. E 4 4

Act. F 6 5

Resource/day

Cumulative resource/day

STEP 1: DRAW BAR CHART (from Example 2), include resource/day for each activity

2

2

2 3

3

3

5

5 2

2

2

6

6

8

8

13

9

5

5

5

5



Resource/ day

4/5

5/5

6/5

7/5

8/5

9/5

10

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11/5

12

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23

/5

24

/5

Act. A 3 2

Act. B 5 3

Act. C 7 2

Act. D 5 4

Act. E 4 4

Act. F 6 5

Resource/day 2

2

2

3

3

3

5

5

2

2

2

6

6

8

8

13

9

5

5

5

5


STEP 2: Calculate the CUMULATIVE resource of each DAY

Cumulative resource (previous) + current resource/day = 2 + 2

2

4

6

9

12

1

5

20

2

5

27

2

9

31

3

7

43

5

1

59

7

2

81

8

6

91

9

6

10

1



Resource/ day

4/5

5/5

6/5

7/5

8/5

9/5

10

/5

11/5

12

/5

13

/5

14

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15

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17

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18/5

19

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20

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21

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22

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23

/5

24

/5

Act. A 3 2

Act. B 5 3

Act. C 7 2

Act. D 5 4

Act. E 4 4

Act. F 6 5

Resource/day 2

2

2

3

3

3

5

5

2

2

2

6

6

8

8

13

9

5

5

5

5


STEP 3: Plot graph base on cumulative resource

2

4

6

9

12

1

5

20

2

5

27

2

9

31

3

7

43

5

1

59

7

2

81

8

6

91

9

6

10

1



Resource/ day

4/5

5/5

6/5

7/5

8/5

9/5

10

/5

11/5

12

/5

13

/5

14

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15

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16

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17

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18/5

19

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20

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21

/5

22

/5

23

/5

24

/5

Act. A 3 2

Act. B 5 3

Act. C 7 2

Act. D 5 4

Act. E 4 4

Act. F 6 5

Resource/day 2

2

2

3

3

3

5

5

2

2

2

6

6

8

8

13

9

5

5

5

5

Cumulative resource/day 2 4 6 9 12

15

20

25

27

29

31

37

43

51

59

72

81

86

91

96

10

1

102

85

68

51

34

17

0


Start from 0

Total cumulative resource

102/6 = 17

102/6 x 2 = 34



Resource/ day

4/5

5/5

6/5

7/5

8/5

9/5

10

/5

11/5

12

/5

13

/5

14

/5

15

/5

16

/5

17

/5

18/5

19

/5

20

/5

21

/5

22

/5

23

/5

24

/5

Act. A 3 2

Act. B 5 3

Act. C 7 2

Act. D 5 4

Act. E 4 4

Act. F 6 5

Resource/day 2

2

2

3

3

3

5

5

2

2

2

6

6

8

8

13

9

5

5

5

5

Cumulative resource/day 2 4 6 9 12

15

20

25

27

29

31

37

43

51

59

72

81

86

91

96

10

1

102

85

68

51

34

17

0


Physical S-Curve (work VS time)



Resources/ day

(person)

Work progress

percentage (%)

1 Activity A 3 4/5/2014 1,400.00 2 12

2 Activity B 5 7/5/2014 2,700.00 3 30

3 Activity C 7 10/5/2014 3,500.00 2 21

4 Activity D 5 15/5/2014 6,000.00 4 10

5 Activity E 4 17/5/2014 4,700.00 4 12

6 Activity F 6 19/5/2014 12,600.00 5 15

30,900.00 100



Work progress

percentage (%)

4/5

5/5

6/5

7/5

8/5

9/5

10

/5

11/5

12

/5

13

/5

14

/5

15

/5

16

/5

17

/5

18/5

19

/5

20

/5

21

/5

22

/5

23

/5

24

/5

Act. A 3 12

Act. B 5 30

Act. C 7 21

Act. D 5 10

Act. E 4 12

Act. F 6 15

Work progress/day

Cumulative work progress/day

STEP 1: DRAW BAR CHART (from Example 2), include work progress

percentage/day for each activity



Work progress

percentage (%)

4/5

5/5

6/5

7/5

8/5

9/5

10

/5

11/5

12

/5

13

/5

14

/5

15

/5

16

/5

17

/5

18/5

19

/5

20

/5

21

/5

22

/5

23

/5

24

/5

Act. A 3 12

Act. B 5 30

Act. C 7 21

Act. D 5 10

Act. E 4 12

Act. F 6 15

Work progress/day


STEP 2: Calculate work progress percentage of each day for every activities

12% / 3 days = 4%/ day 4 4 4

30% / 5days = 6%/ day 6 6 6 6 6

3 3 3 3 3 3 3

2 2 2 2 2

3 3 3 3

2.5 2.5 2.5 2.5 2.5 2.5



Work progress

percentage (%)

4/5

5/5

6/5

7/5

8/5

9/5

10

/5

11/5

12

/5

13

/5

14

/5

15

/5

16

/5

17

/5

18/5

19

/5

20

/5

21

/5

22

/5

23

/5

24

/5

Act. A 3 12

Act. B 5 30

Act. C 7 21

Act. D 5 10

Act. E 4 12

Act. F 6 15

Work progress/day


4

9

4

4

9

3

3

3

5

5

5

5

7.5

5

.5

2.5

2

.5

2.5

2

.5

6

6

6

6 +3

4 4 4

6 6 6 6 6

3 3 3 3 3 3 3

2 2 2 2 2

3 3 3 3

2.5 2.5 2.5 2.5 2.5 2.5

STEP 2: Calculate work progress percentage of each day



Work progress

percentage (%)

4/5

5/5

6/5

7/5

8/5

9/5

10

/5

11/5

12

/5

13

/5

14

/5

15

/5

16

/5

17

/5

18/5

19

/5

20

/5

21

/5

22

/5

23

/5

24

/5

Act. A 3 12

Act. B 5 30

Act. C 7 21

Act. D 5 10

Act. E 4 12

Act. F 6 15

Work progress/day


4

9

4

4

9

3

3

3

5

5

5

5

7.5

5

.5

2.5

2

.5

2.5

2

.5

6

6

6

4 4 4

6 6 6 6 6

3 3 3 3 3 3 3

2 2 2 2 2

3 3 3 3

2.5 2.5 2.5 2.5 2.5 2.5

STEP 3: Calculate cumulative work progress percentage of each day



Work progress

percentage (%)

4/5

5/5

6/5

7/5

8/5

9/5

10

/5

11/5

12

/5

13

/5

14

/5

15

/5

16

/5

17

/5

18/5

19

/5

20

/5

21

/5

22

/5

23

/5

24

/5

Act. A 3 12

Act. B 5 30

Act. C 7 21

Act. D 5 10

Act. E 4 12

Act. F 6 15

Work progress/day


4

8

12

18

24

30

39

48

51

54

57

62

67

72

77

84

.5

90

92

.5

95

97

.5

10

0

4

9

4

4

9

3

3

3

5

5

5

5

7.5

5

.5

2.5

2

.5

2.5

2

.5

6

6

6

4 4 4

6 6 6 6 6

3 3 3 3 3 3 3

2 2 2 2 2

3 3 3 3

2.5 2.5 2.5 2.5 2.5 2.5

STEP 3: Calculate cumulative work progress percentage of each day



Work progress

percentage (%)

4/5

5/5

6/5

7/5

8/5

9/5

10

/5

11/5

12

/5

13

/5

14

/5

15

/5

16

/5

17

/5

18/5

19

/5

20

/5

21

/5

22

/5

23

/5

24

/5

Act. A 3 12

Act. B 5 30

Act. C 7 21

Act. D 5 10

Act. E 4 12

Act. F 6 15

Work progress/day


4

8

12

18

24

30

39

48

51

54

57

62

67

72

77

84

.5

90

92

.5

95

97

.5

10

0

4

9

4

4

9

3

3

3

5

5

5

5

7.5

5

.5

2.5

2

.5

2.5

2

.5

6

6

6

4 4 4

6 6 6 6 6

3 3 3 3 3 3 3

2 2 2 2 2

3 3 3 3

2.5 2.5 2.5 2.5 2.5 2.5

STEP 4: Plot S-curve



Work progress

percentage (%)

4/5

5/5

6/5

7/5

8/5

9/5

10

/5

11/5

12

/5

13

/5

14

/5

15

/5

16

/5

17

/5

18/5

19

/5

20

/5

21

/5

22

/5

23

/5

24

/5

Act. A 3 12

Act. B 5 30

Act. C 7 21

Act. D 5 10

Act. E 4 12

Act. F 6 15

Work progress/day


4

8

12

18

24

30

39

48

51

54

57

62

67

72

77

84

.5

90

92

.5

95

97

.5

10

0

4

9

4

4

9

3

3

3

5

5

5

5

7.5

5

.5

2.5

2

.5

2.5

2

.5

6

6

6

4 4 4

6 6 6 6 6

3 3 3 3 3 3 3

2 2 2 2 2

3 3 3 3

2.5 2.5 2.5 2.5 2.5 2.5

STEP 4: Plot S-curve

100

75

50

25

0

Planning VS Actual S-curve??

Before this, we just create a planning bar chart.

What if, the real activities has started? How to create actual S-curve?

Planning VS Actual S-curve (Example 2) Physical S-Curve (work vs time)

Num. Activity Duration (days)

Start Date Actual Start Date

Actual Finish Date

Cost (RM)

Resources (person)

1 Activity A 3 4/5/2014 4/5/2014 6/5/2014 1,400.00 2

2 Activity B 5 7/5/2014 7/5/2014 12/5/2014 2,700.00 3

3 Activity C 7 10/5/2014 11/5/2014 17/5/2014 3,500.00 2

4 Activity D 5 15/5/2014 17/5/2014 21/5/2014 6,000.00 4

5 Activity E 4 17/5/2014 18/5/2014 22/5/2014 4,700.00 4

6 Activity F 6 19/5/2014 21/5/2014 26/5/2014 12,600.00 5

30,900.00

Planning VS Actual S-curve Activity Duration

(days) Start Date

Actual Start Date

Actual Finish Date

4/5

5/5

6/5

7/5

8/5

9/5

10/5

11/5

12/5

13/5

14/5

15/5

16/5

17/5

18/5

19/5

20/5

21/5

22/5

23/5

24/5

25/5

26/5

Act. A 3 4/5/14 4/5/14 6/5/14

Act. B 5 7/5/14 7/5/14 12/5/14

Act. C 7 10/5/14 11/5/14 17/5/14

Act. D 5 15/5/14

17/5/14 21/5/14

Act. E 4 17/5/14 18/5/14 22/5/14

Act. F 6 19/5/14 21/5/14 26/5/14

Planning cumulative work / day

Actual cumulative work/ day

STEP 1: DRAW BAR CHART (planning and actual)

Planning

Actual

Planning VS Actual S-curve Activity Duration

(days) Start Date

Actual Start Date

Actual Finish Date

4/5

5/5

6/5

7/5

8/5

9/5

10/5

11/5

12/5

13/5

14/5

15/5

16/5

17/5

18/5

19/5

20/5

21/5

22/5

23/5

24/5

25/5

26/5

Act. A 3 4/5/14 4/5/14 6/5/14

Act. B 5 7/5/14 7/5/14 12/5/14

Act. C 7 10/5/14 11/5/14 17/5/14

Act. D 5 15/5/14

17/5/14 21/5/14

Act. E 4 17/5/14 18/5/14 22/5/14

Act. F 6 19/5/14 21/5/14 26/5/14

Planning cumulative work / day

Actual cumulative work/ day

STEP 2: Calculate cumulative for both planning & actual work/day


Start Date

Actual Start Date

Actual Finish Date

4/5

5/5

6/5

7/5

8/5

9/5

10/5

11/5

12/5

13/5

14/5

15/5

16/5

17/5

18/5

19/5

20/5

21/5

22/5

23/5

24/5

25/5

26/5

Act. A 3 4/5/14 4/5/14 6/5/14

Act. B 5 7/5/14 7/5/14 12/5/14

Act. C 7 10/5/14 11/5/14 17/5/14

Act. D 5 15/5/14

17/5/14 21/5/14

Act. E 4 17/5/14 18/5/14 22/5/14

Act. F 6 19/5/14 21/5/14 26/5/14

Planning cumulative work / day 1 2 3 4 5 6 8 10 11 12 13 15 17 19 21 24 26 27 28 29 30

Actual cumulative work/ day 1 2 3 4 5 6 7 9 11 12 13 14 15 17 19 21 23 26 28 29 30 31 32

STEP 2: Calculate cumulative for both planning & actual work/day

Planning VS Actual S-curve


Start Date

Actual Start Date

Actual Finish Date

4/5

5/5

6/5

7/5

8/5

9/5

10/5

11/5

12/5

13/5

14/5

15/5

16/5

17/5

18/5

19/5

20/5

21/5

22/5

23/5

24/5

25/5

26/5

Act. A 3 4/5/14 4/5/14 6/5/14

Act. B 5 7/5/14 7/5/14 12/5/14

Act. C 7 10/5/14 11/5/14 17/5/14

Act. D 5 15/5/14

17/5/14 21/5/14

Act. E 4 17/5/14 18/5/14 22/5/14

Act. F 6 19/5/14 21/5/14 26/5/14



Planning VS Actual S-curve STEP 3: Plot the S -curves


Start Date

Actual Start Date

Actual Finish Date

4/5

5/5

6/5

7/5

8/5

9/5

10/5

11/5

12/5

13/5

14/5

15/5

16/5

17/5

18/5

19/5

20/5

21/5

22/5

23/5

24/5

25/5

26/5

Act. A 3 4/5/14 4/5/14 6/5/14

Act. B 5 7/5/14 7/5/14 12/5/14

Act. C 7 10/5/14 11/5/14 17/5/14

Act. D 5 15/5/14

17/5/14 21/5/14

Act. E 4 17/5/14 18/5/14 22/5/14

Act. F 6 19/5/14 21/5/14 26/5/14



Planning

Actual

STEP 3: Plot the S -curves

Planning VS Actual S-curve

Arrow Diagram Method (ADM) -Activity-on-Arrow (AOA) Network

Precedence Diagram Method (PDM) - Activity-on-Nodes (AON) Network

Network Diagram Activity on Arrow (AOA)/ Arrow Diagram

Method (ADM) In arrow diagram project task or activities are

represented by the arrow and connected by the node to express their logical relationship

Node represents an event. An activity starts or ends at a node.

Activity A

Node

Activity B

Node Node

ADM

Pour concrete Fixed rebar Fixed fwk

Fabricated rebar

Excavate trench

Fabricated formwork

Diagram for construction of pad footing

Network Diagram Activity on Node (AON)/ Precedence Diagram

Method (PDM)

activity is place on the node

The arrow used to connect between project task to show their logical relationship

Act. A Act. B

Node Node

Network Diagram

Diagram for construction of pad footing Arrow - Logical Node - Activity Logical Show the relationship between activities - Sequences of interrelated activity

Basic definition in network diagram

Activity- the performance of a task required to complete the project. An activity require time, cost, or both.

Network- a diagram to represent the relationship of activities to complete a project. The network may be drawn as ADM or PDM.

Duration- the estimated time required to perform an activity.

Activity Sequencing

Understand the order of how the job to be accomplished in the field.

The planner must understand how various activities of the project related to each other in term of their logical sequence.

Example preparing formwork before reinforcement could be place & than pouring concrete.

Activity Sequencing

Predecessor

A task whose start or finish date determines the start or finish date of its successor task.

Successor

A task whose start or finish date is driven by its predecessor task.

ADM vs. PDM

Item ADM PDM

Activity

Activities shown as an arrow or sometimes as a line.

ES: Early Start LS: Late Start

EF: Early Finish LF: Late Finish

D : Duration TF: Total Float

Activities shown on node.

Event/ Node

2 events / nodes

1 event

A ES EF

LS LF

A

D

TF

ES EF

LS LF

A D

TF

ES EF

LS LF

B D

TF

1 ES

LS 1

EF

LF 2

A

ADM vs. PDM ADM PDM

Early Start (ES) is the earliest possible time an activity can start.

Late Finish (LF) is the latest possible time an activity can finish without extending the completion date of the project.

Total float (TF)- the amount of time an activity may be delayed without delaying the completion date of the project.

TF = LF ES D or TF = LS ES or TF = LF EF

Free float (FF)- the amount of time an activity may be delayed without delaying the early start time of the

immediately following activity.

FF(i) = ES(j) EF(i) ; i-preceding activity, j-following activity

Late Start (LS) is the latest possible time an activity can start without extending the completing date of the project.

LS = LF - D

Early Finish (EF) is the earliest possible time an activity can finish if it is start on Early Start Time (ES) and finish within the planned duration.

EF = ES + D *D = duration

ADM vs. PDM ADM

-A and B are activities. 1, 2 and 3 are events

-Activity A has ID or label 1-2 ; Activity B has ID or label 2-3

-Activity A precedes activity B

PDM

1 2 A

ES EF

LS LF

A D

TF

ES EF

LS LF

B D

TF

1

3 B

ES EF

LS LF

B D

TF

2

Activity Nodes

Predecessor Activity

Current Activity

Successor Activity

ADM vs. PDM Item ADM PDM

Relationshi

p

F S

ADM only shows finish-to-

start relationships, meaning

that each activity is

completed before the

successor activity starts.

F S F F S S S - F

Critical

path

- Critical Path

- A series of interconnected activities through the network

diagram, with each activity having zero total float time. The

critical path determines the minimum time to complete the

project.

- Possible to have more than one critical path

- Activities which lay on critical path cannot suffer any delay

1. ESX = LSX, or

2. LFX = EFX, or

3. Total Float (TF) = 0

ADM vs. PDM Item ADM PDM

Dummy Activity

or

Definition

An activity that

indicates any activity

following the dummy

cannot be started until

the activity(ies)

preceding the dummy are

completed.

Activity which has not

duration. It is only used

to show any relationship

between activities.

Function

If there is a situation

where one event is used

to show relationship more

than one activity.

To show a complicated

relationship clearly

Dummy activity is not used

in Precedence Diagram

Method (PDM)

D

Item ADM

Dummy Activity

or

False

True

D

1 2 1 2

3

A

B

A

B

C

D

A

B

A

B

C

D

Activity A & B have the same

ID

A: 1-2

B: 1-2

ID for Activity A & B are not

same.

A: 1-2

B: 1-3

If C is to follow A & B,

but D is to follow only B.

(not fulfill)

If C is to follow A & B,

but D is to follow only B.

(use dummy)

Item ADM

Dummy Activity

or

False

True

D

A 1 2 Q

3 B

4

P

R

If P, Q and R follow A, and B follows P, Q and R. The following diagram is not the correct representation of the same.

A 1 2 Q

3 B

4

P

R

5

6

Reason: Activities P, Q and R have the same ID (2-3).

Activities P has the ID (2-5), Q (2-3) and R (2-6).

Item ADM

Dummy Activity

or

False

True

D

1. D is preceded by A only 2. E is preceded by A and B 3. F is preceded by B and C

A

B

C

D

F

E

A

B

C

D

F

E

Statement 3 not fulfill

where F is preceded by

A, B and C.

92

ADM vs. PDM

Item ADM PDM

Estimating

duration

- FORWARD PASS

: To establish the earliest expected start and finish times for each activity in the network.

- BACKWARD PASS

: To establish the latest allowable start and finish times for each activity in the network.

Early Start

Early Finish

Late Start

Late Finish

FORWARD PASS

BACKWARD PASS

93

Arrow Diagram Method

A 1

a

b 2 c

d X

B 3 e

f Y

Forward pass

Backward pass

Note a : Early Start (ES)A b : Late Start (LS)A c : Early Finish (EF)A = (ES)B d : Late Finish (LF)A = (EF)B e : Early Finish (EF)B

f : Late Finish (LF)B X : Duration of activity A

Y : Duration of activity B

Forward pass Backward pass a = 0 f = e

c = a + X d = f Y

e = c + Y b = d - X

c = a + X e = c + Y

d = f Y

ACTIVITY DURATION(DAY) PREDECESSOR

A 3 -

B 5 A

C 3 B

D 4 -

E 4 A

F 10 E,D

G 9 C,F

1

2 3

5

4

6

A

D

B

E

C

F

G 3

5

3

4 10

4 9

ACTIVITY DURATION (DAY)

PREDECESSOR

A 3 -

B 5 A

C 3 B

D 4 -

E 4 A

F 10 E,D

G 9 C,F

1

2 3

5

4

6

A

D

B

E

C

F

G 3

5

3

4 10

4 9

Early Start Box

Early Finish Box

Early Start at node 1 is zero

Make forward pass through the network by adding duration times.

0

0+3=3

3

1

2 3

5

4

6

A

D

B

E

C

F

G 3

5

3

4 10

4 9

Early Start Box Early Finish Box

Make forward pass through the network by adding duration times.

0

3+5=8 3 8

1

2 3

5

4

6

A

D

B

E

C

F

G 3

5

3

4 10

4 9

0

3 8

If two or more activities terminate at a junction node, place the larger sum at ES box.

3+4=7

0+4=4 Larger=7

7

1

2 3

5

4

6

A

D

B

E

C

F

G 3

5

3

4 10

4 9

0

3 8

7

17 26

1

2 3

5

4

6

A

D

B

E

C

F

G 3

5

3

4 10

4 9

0

3 8

7

17 26

Enter 26 into Late Finish box at the node 6, and make a backward pass to establish LF for each activity by deducting the durations.

26

Early finish of activity G in the node 6 =26 days. Thats means it will take 26 days to complete the project. Therefore, 26 days represents Late Finish of the project.

1

2 3

5

4

6

A

D

B

E

C

F

G 3

5

3

4 10

4

9

0

3 8

7

17 26

26

26-9=17

17

14

7

In the case of junction nodes (with two or more activities), place the smaller value in the LF box of that node.

14-5=9

7-4=3

3 Smaller=3

0

1

2 3

5

4

6

A

D

B

E

C

F

G 3

5

3

4 10

4

9

0

3 8

7

17 26

26 17

14

7

3

0

1

2 3

5

4

6

A

D

B

E

C

F

G 3

5

3

4 10

4

9

0

3 8

7

17 26

26 17

14

7

3

0

Total Float (TF) =LF-D-ES

TFA = LF-D-ES =3-3-0

=0

TFA=0

TFB=6

TFC=6

TFD=3

TFE=0

TFF=0

TFG=0

TFB = LF-D-ES =14-5-3

=6

1

2 3

5

4

6

A

D

B

E

C

F

G 3

5

3

4 10

4

9

0

3 8

7

17 26

26 17

14

7

3

0

Activities on critical path : A,E,F and G.

TFA=0

TFB=6

TFC=6

TFD=3

TFE=0

TFF=0

TFG=0

ACTIVITY DURATION(DAY) ES EF LS LF TF

A 3 0 3 0 3 0*

B 5 3 8 3 14 6

C 3 8 17 14 17 6

D 4 0 7 0 7 3

E 4 3 7 3 7 0*

F 10 7 17 7 17 0*

G 9 17 26 17 26 0*

* Critical Activity

Total Float (TF) =LF-D-ES

BAR CHART


1 2 3 4 5 6 7 8 9 10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

A 3

B 5

C 3

D 4

E 4

F 10

G 9


ES EF LS LF TF

A 3 0 3 0 3 0*

B 5 3 8 3 14 6

C 3 8 17 14 17 6

D 4 0 7 0 7 3

E 4 3 7 3 7 0*

F 10 7 17 7 17 0*

G 9 17 26 17 26 0*

Example 2 (ADM) Activity Duration (day) Predecessor (s)

Act. A 2 -

Act. B 3 -

Act. C 3 A

Act. D 4 B

Act. E 3 C,D

Act. F 2 C,D

Act. G 4 E

Act. H 3 F

1. Develop an arrow diagram for the project. 2. Identify critical activity and critical path for the project.

1

2

4

5

3

7

A

B

C

D

E

F

G

2 3

3

3 2 4

4

Activity Duration (day) Predecessor (s)

Act. A 2 -

Act. B 3 -

Act. C 3 A

Act. D 4 B

Act. E 3 C,D

Act. F 2 C,D

Act. G 4 E

Act. H 3 F

6

H

3

1

2

4

5

3

7

A

B

C

D

E

F

G

2 3

3

3 2 4

4

6

H

3

Forward pass

0

2

3

7

10

9

14

1

2

4

5

3

7

A

B

C

D

E

F

G

2 3

3

3 2 4

4

6

H

3

Backward pass

0

2

3

7

10

9

14

14

11

10

7

3

0

4

Total Float

Activity Duration (day)

ES EF LS LF TF

Act. A 2 0 2 0 4 2

Act. B 3 0 3 0 3 0*

Act. C 3 2 7 4 7 2

Act. D 4 3 7 3 7 0*

Act. E 3 7 10 7 10 0*

Act. F 2 7 9 7 11 2

Act. G 4 10 14 10 14 0*

Act. H 3 9 14 11 14 2

* Critical Activity Total Float (TF) =LF-D-ES

2

4

5

3

7

A

B

C

D

E

F

G

2 3

3

3 2 4

4

6

H

3

Critical Path

2

3

7

10

9

14

14

11

10

7

3

1 0

0

4

Critical path Activities on critical path : B,D,E and G.

Exercise 3 (ADM)

Prepare a arrow diagram for the project. Identify critical path for the project.


Act. A 2 -

Act. B 3 A

Act. C 5 A

Act. D 4 A

Act. E 2 B,C

Act. F 3 C

Act. G 4 C,D

Act. H 2 E,F,G

A C

Exercise 3 Forward pass

D 4

B 3

F 3

H 1

0 2

2 3

7

4 7

6 11 7

13

5 7

2 2 5

5,7

6,7

9,10,11

A C

Exercise 3 Backward pass

D 4

B 3

F 3

H 1

0

0 2

2

2 3

7

7

4 7

9

6 11

11 7

13

13

5 7

7

2 2 5

9,8,7

6,2,3

A 2

C 5

Exercise 3 (ADM-Solution)

Critical path

D 4

B 3

F 3

H 2

1 0

0 2

2

2 3

7

7

4 7

9

6 11

11 7

13

13

5 7

7

Activities on critical path : A,C,G and H.

Link (Relationship)

Finish to Start (FS)

Activity B cannot start until Activity A finish

Start to Start (SS)

Activity B cannot start until Activity A start

Act. A Act. B

Act. A

Act. B

Finish to Finish (FF)

Activity B cannot finish until Activity A finish.

Start to Finish (SF)

Activity B cannot finish until Activity A start.

Act. A

Act. B

Act. A

Act. B

Link (Relationship)

Lead time & lag time

Lead time Overlap between

dependent activity

Eg : FS 5d

Lag time Delay between

dependent activity

Eg: FS + 2 d

Act. A

Act. B

5d

Act. A

Act. B

2d

ACTIVITY DURATION(DAY) PREDECESSOR

A 2 START

B 6 A

C 6 B

D 1 B

E 3 A

F 3 D,E

G 2 C(+2),F

A

2

B

6

C

6

D

1

E

3

F

3

G

2 FS +2

EXAMPLE 1


PREDECESSOR

A 2 START

B 6 A

C 6 B

D 1 B

E 3 A

F 3 D,E

G 2 C(+2),F

ES LS D

LS LF TF

Activity

A

2 0 2

B

6 2 8

C

6 8 14

D

1 8 9

E

3 2 5

F

3 9 12

G

2 16 18

16,12

FS +2

5,9

FORWARD PASS

EXAMPLE 1

A

2 0 2

B

6 2 8

C

6 8 14

D

1 8 9

E

3 2 5

F

3 9 12

G

2 16 18

16,12

FS +2

5,9

EXAMPLE 1

18 16

16

BACKWARD PASS

A

2 0 2

B

6 2 8

C

6 8 14

D

1 8 9

E

3 2 5

F

3 9 12

G

2 16 18

16,12

FS +2

5,9

EXAMPLE 1

2 2 8 8 14

12 13

18 16

16 13

13 10

8,12 2,10

BACKWARD PASS

A

2 0 2

B

6 2 8

C

6 8 14

D

1 8 9

E

3 2 5

F

3 9 12

G

2 16 18

16,12

FS +2

5,9

EXAMPLE 1

0 2 2 8 8 14

12 13

18 16

16 13

13 10

8,12 2,10

BACKWARD PASS

A

2 0 2

0 2

B

6 2 8

2 8

C

6 8 14

8 14

D

1 8 9

12 13

E

3 2 5

F

3 9 12

G

2 16 18

16,12

FS +2

5,9

18 16

16 13

13 10

8,12 2,10

COMPLETED

EXAMPLE 1

127

A

2 0 2

0 2

B

6 2 8

2 8

C

6 8 14

8 14

D

1 8 9

12 13

E

3 2 5

F

3 9 12

G

2 16 18 FS +2

18 16

16 13

13 10

TOTAL FLOAT

EXAMPLE 1

TFA = LF-EF

=2-2

=0

TFB = LF-EF

=8-8

=0

TFC = LF-EF

=14-14

=0

TFD = LF-EF

=13-9

=4

TFE = LF-EF

=13-5 =8

TFG = LF-EF

=18-18

=0

TFF = LF-EF

=16-12

=4

0 0

4

8

0

4

0

128

A

2 0 2

0 2

B

6 2 8

2 8

C

6 8 14

8 14

D

1 8 9

12 13

E

3 2 5

F

3 9 12

G

2 16 18 FS +2

18 16

16 13

13 10

FREE FLOAT

EXAMPLE 1

FFA = ESSUCC-EF-

Lag

=2-2-0

=0

0 0

4

8

0

4

0

FFB = ESSUCC-EF-

Lag

=8-8-0

=0

FFC = ESSUCC-EF-

Lag

=16-14-2

=0

FFD = ESSUCC-EF-

Lag

=9-9-0

=0

FFF = ESSUCC-EF-

Lag

=16-12-0

=4

FFA = ESSUCC-

EF- Lag

=18-18-

0

=0

A

2 0 2

0 2

B

6 2 8

2 8

C

6 8 14

8 14

D

1 8 9

12 13

F

3 9 12

G

2 16 18

16,12

FS +2

5,9

18 16

16 13

8,12 2,10

CRITICAL PATH

EXAMPLE 1

0 0

4

E

3 2 5

13 10 8

0

4

0

Example 2 (PDM) Activity Duration (day) Predecessor (s)

Act. A 10 -

Act. B 11 A

Act. C 5 B

Act. D 4 B

Act. E 12 A

Act. F 3 C,D

Act. G 7 F

Act. H 11 E

Act. I 4 G,H

1. Develop a precedence diagram for the project. 2. Identify critical activity and critical path for the project.

Example 2 (PDM)

A

10

B

11

E

12

H

11

I

4

ES LS D

LS LF TF

Activity

C

5

D

4

F

3

G

7

Example 2 (PDM-forward pass)

A

10 0 10

B

11 10 21

E

12 10 22

H

11 22 33

I

4 36 40

ES LS D

LS LF TF

Activity

C

5 21 26

D

4 21 25

F

3 26 29

G

7 29 36

Example 2 (PDM-backward pass)

A

10 0 10

10 0

B

11 10 21

21 10

E

12 10 22

25 13

H

11 22 33

36 25

I

4 36 40

40 36

ES LS D

LS LF TF

Activity

C

5 21 26

26 21

D

4 21 25

26 22

F

3 26 29

29 26

G

7 29 36

36 29

Example 2 (PDM-Total float)

A

10 0 10

10 0 0

B

11 10 21

21 10 0

E

12 10 22

25 13 3

H

11 22 33

36 25 3

I

4 36 40

40 36 0

ES LS D

LS LF TF

Activity

C

5 21 26

26 21 0

D

4 21 25

26 22 1

F

3 26 29

29 26 0

G

7 29 36

36 29 0

Critical path TF = LF ES D or TF = LS ES or TF = LF EF

Example 3 (PDM) Activity Duration (week) Predecessor (s)

Act. A 2 -

Act. B 3 A (FS+2), C (FF+1),

D(FF)

Act. C 2 A

Act. D 1 C (SS)

1. Develop a precedence diagram for the project. 2. Identify critical activity and critical path for the project.

Example 3 (PDM-forward pass)

+2

+1

A

2 0 2

B

3 4 7

C

2 2 4

D

1 2 3

Example 3 (PDM-backward pass)

Critical path

+2

+1

Total Float = LF ES D TF(A) = 2-0-2 = 0 TF(B) = 7-4-3 = 0 TF(C) = 6-2-2 = 2 TF(D) = 7-2-1 = 4

A

2 0 2

2 0 0

B

3 4 7

7 4 0

C

2 2 4

6 4 2

D

1 2 3

7 6 4

Exercise 4(PDM)

Prepare a precedence diagram for the project. Identify critical path for the project.


Act. A 2 -

Act. B 3 A

Act. C 5 A

Act. D 4 A

Act. E 2 B,C

Act. F 3 C

Act. G 4 C,D

Act. H 2 E,F,G

Exercise (PDM-Solution)

A

2 0 2

2 0 0

B

3 2 5

9 6 4

C

5 2 7

7 2 0

D

4 2 6

7 3 1

E

2 7 9

11 9 2

F

3 7 10

11 8 1

G

4 7 11

11 7 0

H

2 11 13

13 11 0

BUT WAIT!!

Are there any other type of Scheduling method??

How if the Gantt Chart and CPM did not actually work/represent well with the nature/requirement of the particular construction project??

So, actually we have LINEAR SCHEDULING METHOD (LSM) / LINE OF BALANCE (LOB)

This method is actually appropriate for a project that:

Progress linearly (straight without major fluctuation of activities),

Highly repetitive works,

Have fixed starting point and end,

Such as; highways, airfields, pipelines, multiple housing units, high-rise buildings, etc.

LINEAR SCHEDULING METHOD (LSM) (cont.)

Take for example; a highway construction project:

LINEAR SCHEDULING METHOD (LSM) (cont.)

LSM Diagram for highway project (adopted from Nunnally, 2014)

Kilo

met

er (

km)

We have 5 linear activities: 1. Clear & strip 2. Drainage 3. Subgrade 4. Base course 5. Pave Width of B: At 40km, the subgrade works will starts at week 4.4 until week 5. Height of A: At week 3, subgrade works from 13km to 21km. Distance of C: It is a time lag / time float for 10km; between subgrade works and base course works. 1.4 weeks to be exact.

QUESTION 2

A project have a detail as below:

1. Draw the precedence diagram for the schedule shown next.

2. Determine the duration of project required.

3. Determine the Total Float for each activities and give the critical path for this project.

4. Draw a bar chart.

ACTIVITY PREDECESSOR DURATION (WEEK) A - 3 B - 1 C - 2 D A 3 E B 1 F C 4 G D 2 H D,E 1 I D,E,F 2 J G 3 K H 2 L I 1 M J,K,L 2

ACTIVITY SUCESSOR DURATION

(WEEK) A A-B (S-S),L=5 3 A-C (F-S),L=2 B B-E (F-S),L=3 1 C C-E (F-S),L=0 2 D D-E (F-S),L=0 2 E E-F (F-S),L=0 3 F 2

1. Draw the precedence diagram for the schedule shown next. 2. Determine the duration of project required. 3. Determine the Total Float for each activities and give the critical path for this project. 4. Draw a bar chart.

No. Activity Duration (week)

Successor Relationship Lag (week)

1 A 5 B, C, D AB (SS) AC (FS) AD (FS)

1 2 0

2 B 4 E BE (FS) 0 3 C 3 F, G CF (FS)

CG (FS) 0 0

4 D 2 H DH (FS) 0 5 E 7 F, G EF (FS)

EG (FS) 0 0

6 F 2 I FI (FS) 0 7 G 5 I GI (FS) 0 8 H 3 I HI (FS) 3 9 I 6 - - -

1. Estimate the total project duration. 2. Calculate the total float for each activity in the project. 3. State the critical path.

Chapter 5 Scheduling Tracking Work

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Transcript of Chapter 5 Scheduling Tracking Work