Scheduling Flashcards
Direct Cost
Any cost that can be associated with the discreet physical part of a project.
Ex. Someone tying rebar.
Indirect Cost
Any cost that cannot be associated with the discreet physical part of a project.
Ex. Someone supervising the tying of rebar.
Logical Limit
of days to reduce before creating another critical path.
Physical Limit
Most # of days to reduce as possible.
Total Float
Max # of days to delay a step w/o affecting the total project duration but affecting floats of following steps.
Free Float
Max # of days to delay a step w/o affecting the total project duration and any following steps’ floats.
(ES of IPA - ES of act. - duration of act.)
Interfering Float
Part of the Total Float which causes a reduction in the float of successor activities.
(TF - FF)
Critical Path
Longest interconnected path through the network; the length of which equals the project duration.
Why crash a schedule?
- to shorten a project
- if delays in project, crash to meet completjon date
- to meet a completion date
- To give contractors more flexibility with deadlines
- Finish project sooneru
- Free up crews for other projects
Steps involved in schedule crashing
- Forward and backward pass
- Get floats (TF, IF, FF)
- Identify critical path
- Determine duration of paths. Find the longest.
- Find crashable activities
- Find logical and physical limits
- Crash by shorter of two
- Repeat
- Crash critical paths simultaneously
Slack
TF and FF of activities
Work breakdown structure (WBS)
Identify specific activities of work required.
Non-network schedule
Gantt Chart
- difficult to show/calculate effects of delays, changes. etc.
Network Schedules
- CPM (Critical Path Method) diagrams
- AOA and AON - PERT (Program Evaluation and Review Technique)
AOA diagrams
- Arrows (lines) represent activities
- Nodes represent points in time
- dummy arrows
