Scheduling

Question 1

Definitions for Network Calculations
ES?

Answer 1

Early start = Latest Early finish of all Immediately preceding activities (IPA)

Question 2

Definitions for Network Calculations
EF?

Answer 2

Early Finish = Early Start + Duration

Question 3

Definitions for Network Calculations
LF

Answer 3

Late Finish = Earliest Late start of succeeding activities

Question 4

Definitions for Network Calculations
LS

Answer 4

Late start = Late finish - duration

Question 5

Definitions for Network Calculations
TF

Answer 5

Total Float = The maximum that the ES of an activity can be delayed without changing the overall project duration for a given activity= Late start - Early start

Question 6

Definitions for Network Calculations
FF

Answer 6

Free float = The maximum that the ES of an activity can be delayed without changing the ES of ANY immediately following activity.

Question 7

Definitions for Network Calculations
CP

Answer 7

Critical path = the longest interconnected path through the network. the length of which equals the project duration activities

Question 8

Things that are accounted for in the construction planning phase

Answer 8

1. The identification of specific activities of work required and the interrelationships between those items (precedence relationships)
2. the proper sequencing of the specific activities of work in order to complete the project in an optimum amount of time
3. the time for delivery of materials and installed equipment
4. the types, quantities, and duration of use of construction equipment
5. the classification and number of workers required and the periods of time they will be required
6. the amount and timing of financial assistance required

Question 9

What is Work Breakdown Structure(WBS)?

Answer 9

the progressive hierarchical breakdown of the project into smaller pieces to the lowest practical level to which costs can be applied

Question 10

Types of Construction Schedules

Answer 10

Bar Gantt Charts
Network Schedules (Critical Path Method diagrams)
-Activity on arrow diagram
-Activity on node diagram

Question 11

What is a Critical Path Schedule?

Answer 11

-Relationships between activities are shown (precedence relationships)
-Critical activities determine project duration and indicate critical path

Question 12

Activity on arrow diagrams (Critical path Method)

Answer 12

-arrows represent activities
-Nodes represent points in time

Question 13

Activity on node diagrams (Critical Path Method)

Answer 13

-node boxes represent the activities
-arrows indicate relationships between nodes

Question 14

Activity on Node diagrams

Answer 14

-boxes at nodes represent the activity
-lines show the interrelationship of activities
-uses a “finish-start” relationship between dependent activities
-easier to draw than arrow diagrams

Question 15

Negative Total Float on Critical Path

Answer 15

-The contract may call for a completion time of 180 workdays
-Forward pass gives total time of 190 workdays
-start backward pass at 180 –all critical activities have TF = -10
-Must save 10 days throughout project

Question 16

Positive Total Float on Critical Path

Answer 16

-Contract may call for a completion time of 215 workdays
-forward pass give total time of 190 workdays
-start backward pass at 215 – all critical activities have TF = +25: non-critical have TF > 25

Question 17

Bar (gantt) Charts

Answer 17

-non-network schedule
-easy to create and understand
-shows the logical interrelationship between activities
-can be updated to show project status
-difficult to show/calculate effects of delays/changes
-does not provide as much useful information as a network schedule

Question 18

Direct Cost

Answer 18

any cost that you can associate with the DISCRETE physical part of a construction project

Question 19

Indirect Cost

Answer 19

any cost that CANNOT be associated with the physical part of a construction project

Question 20

Why may a contractor want to finish the project quickly? (Schedule crash)

Answer 20

-To get onto another project as they always submit multiple bids
-Behind schedule, to get back on schedule
-Owner wants it finished faster and may compensate the cost

Question 21

Outline the procedure for crashing a schedule

Answer 21

1. find the initial project duration
2. indirect cost
3. total direct cost
4. total cost
5. next longest path
6. number of critical paths
7. critical activities
8. activity with lowest cost slope
9. maximum shortening (logical and physical limit)