CM - Project Planning, Scheduling & networks Flashcards
What are the advantages of using a Bar/Gantt chart for scheduling?
Simple, represents progress - commonly used for communicating between trades.
What are the disadvantages of using a Bar/Gantt chart?
Difficult to show logic, or update based on revised logic.
What is the main purpose of using a Bar/Gantt chart ?
To communicate a construction schedule and monitor progress.
What is the advanatage of using an Activity-on-node (AON) network?
Represents logical relationships between activities, and suitable for most cocnstruction.
What are the disadvanatages of using an AON network?
Complex to produce, and works best for FS activities.
What is the main purpose of an AON schedule?
To devise a construction schedule.
What is the modern approach of scheduling?
Using software to present a Gantt chart and use the principle of scheduling networks.
What is the critical path method? (CPM)
An algorithm for schduling a set of activities.
What are the aims of the critical path method?
To dtermine the duration of a project, and the implication of delays on the overall project duration.
What is the ‘critical path’, when talking about the critical path method?
The sequence of activites with the overall greatest duration.
What are the 7 steps taken in the critical path method?
1 - Identify required activities using WBS
2 - Estimate activity duration
3 - Determine construction sequence
4 - Draw network
5 - Forward pass
6 - Backward pass
7 - Calculate total float, free float and the CRITICAL PATH
What is a ‘forward’ and ‘backward’ pass?
Forward pass = Calculate Early start
Backward pass = Calculate late start and late finish
What does an Early start mean?
It starts at the earliest finish of the predecessor.
What does an early finish mean?
Early start + duration
What does a late start mean?
Late finish - duration
What does a late finish mean?
Late start of the earliest successor.
What is schedule contingency?
The amount of time included in the schedule to mitigate the effects of uncertainty.
What are some of the reasons for schedule contingency?
Incomplete designs, environmental factors, availability of resources, accidents, changes, etc.
What are the 2 approaches of taking ‘schedule contingency’ into account?
1 - Add a time contingency at the end of the network considering delays for different impact factors.
2 - Add a time contingency for each activity.
What does a milestone anticipate?
What the project is supposed to achieve at a pre set date.
Does a milestone refer to a point in time, or a period of time?
A point in time
What should milestones be associated with?
An anticipated completion date, i.e. a deadline.
