The Open University of Sri Lanka
P.G. Diploma in Construction Management Programme – Level 7
CEX 7101 – Planning and Control in the Construction Industry
Assignment 2- Academic year 2016
Submit answers to: Course Coordinator CEX 7101,
Department of Civil Engineering, The Open University of Sri Lanka,
Nawala, Nugegoda.
______________________________________________________________________
Date of submission as indicated in the Activity Schedule or amended thereafter.
Answer all questions with assumptions stated clearly.
 Refer your hand out on General Information. Type written answers are expected.
Q1. An oil refinery is planning the installation of a gas turbine based combined heat and
power system. The gas turbine will be housed in a new building next to a furnace which
uses the exhaust gas for pre-heating its air supply. The layout and activities are shown
below.
Turbine
House
Ducting
Furnace
Fuel
Tank
Table 1
No
1
2
3
4
5
6
7
8
9
10
11
12
13
Task
Finalise design
Procure generating set
Procure switch gear and control system
Manufacture ducting
Procure fuel tank
Build turbine house
Erect support structure for ducting
Erect support structure for fuel tank
Install ducting
Install fuel tank
Install generator
Install switch gear and control system
Commission
1
Duration
(weeks)
6
20
24
6
2
8
3
3
1
1
2
2
2
Design work can start immediately. The following conditions apply with regard to
precedence requirements.
 The design work can start immediately and must be complete before procurement
tasks can start
 The building work must be completed before the generator and switchgear can be
installed and the support structures started
 The generator must be installed before the ducting
 The respective support structures must be installed before the fuel tank and
ducting can be installed
 Commissioning takes place when all other tasks are completed
(a) Draw a activity-on-node diagram for the project and indicate the earliest start times,
latest start times, earliest finish times and latest finish times for each activity.
(b) Calculate the total floats for each activity and comment on the events that have
longest float
(c)Identify the critical path and state the minimum duration for the project.
(Total 40 marks)
Q2.
(a) Illustrate the usefulness of deviating from the conventional presentation of bar
charts to more dynamic and innovative forms.
(b)
A set of activities for a project are given below. The man power requirement per day
of activity is also given.
Table 2
Activity
A
B
C
D
E
F
G
Duration
(days)
2
4
8
5
7
2
3
Preceding
activity
A
A
B,C
D
E,F
Labour requirement per
day
4
3
11
7
3
3
6
(i) Draw the complete activity-on-arrow network diagram indicating the activity
times and the critical path.
(ii) Prepare bar charts based on early start time and late start time.
(iii)Perform resource smoothening and draw the histogram for Labour after leveling
(Total 35 marks)
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Q3.
Write short notes on all five of the following:
(a) Citing an example explain the use of ‘Work breakdown structures & Work
packages’ in the management of a small construction project
(b) State the advantages of using sub-nets in network construction
(c) Explain how you can exercise Progress Control on a project where the
work programme is based on the critical path method
(d) State the factors which affect the choice of a ‘planning technique’ for a
construction project giving reasons
(e) There are several dimensions to the problem of ‘underemployment’. State
them in brief.
(5 marks each = 25 marks)
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