Week 3

Question 1

What does the Project Programming /Scheduling consist of?

Answer 1

1. Work Breakdown Structure. (Decompose project into a Work Breakdown Structure (WBS) defining Work Packages (WPs)).
2. Activity Programming (WPs are defined so that resources, time (and cost) for each of them can be estimated, a process called WP Programming (or Activity Programming)).
3. Project Logic Evaluation. (To assess project duration, it is necessary to develop suitable Network Logic - the relationships between different activities.)
4. Network Analysis. (Once the logic has been determined, a Network Analysis/ Optimisation methods can be used to calculate project duration, etc. (Critical Path Method, CPM).)

Question 2

What is the goal of Network Analysis?

Answer 2

• Calculate completion time.
• Calculate start and finish date for each activity.
• Identify critical activities.
• Identify requirements and flows of resources (materials, labour and equipment, £).

Question 3

Mention some Network Analysis methods.

Answer 3

• Critical Path method (CPM).
• Programme Evaluation Review Technique (PERT).
• Monte Carlo Simulation.
• Linear Scheduling Method (LSM).

Question 4

Explain CPM in detail.

Answer 4

• Assumes fixed duration for each activity (i.e. WP)
  -Delivers:
  -Shortest completion time.
  
  • For each activity:
    -Earliest and Latest Start times (ES and LS) and
    consequently Earliest and Latest Finish times (EF and
    LF).
    
    • Float (F) available.
      -Critical Path.
• Two representations:
  -Network Precedence Diagram.
  
  • Gantt Chart.

Question 5

What are the different types of Precedence Relations?

Answer 5

• Finish-to-Start (FS)
  Activity B must start efter Activity A is finished.
  -Start-to-Start (SS)
  Activity B must start when Activity A starts.
• Finish-to-Finish (FF)
  Activity B must finish when Activity A finishes.
• Start-to-Finish
  Activity B must finish when Activity A starts.

Question 6

What is the procedure for CPM?

Answer 6

1. Assign durations to activities in network diagram.
2. Calculate ES and EF for each activity –> Completion time.
3. Calculate LS and LF for each activity –> Total Float.
4. Identify Critical Path.
5. Identify resource requirements and potential problems.

Question 7

How do you calculate Total Float (TF)?

Answer 7

TF = LF - ES - D

TF = LS - ES

TF = LF - EF

Question 8

What does TF=0 mean?

Answer 8

It means that there is no programming flexibility

Question 9

Give examples of Activity Resources.

Answer 9

• Time
• Precedence
• Labour
• Material
• Equipment
• Space
• Money

Question 10

What can be done to combat resource constraints?

Answer 10

Software can address global resource constraints.

Planner can use artificial precedence to ensure resources are not needed simultaneously.

Question 11

What are the consequences of Sub-optimality?

Answer 11

Due to a lack of consideration for resource demand over time, the project can have sub-optimal results. The consequences are:

• Cost of unproductive resources in situation of underallocation.
• Cost (and risk) of managing resource demand fluctuations. (Mobilisation/Demobilisation)

Question 12

What is Resource Levelling?

Answer 12

• It balances resource demand over time.
• Very important to enable smooth site operations.
• Software can often not do that.