Schedule Compression and Time-Cost Trade-Off - Construction Project Scheduling and Control - page 232

Example 8.1

Calculate the normal, least-cost, and crash durations for the following project.
Calculate the cost associated with each duration. Indirect (overhead) costs
are $120 per day.

Duration (days) Cost ($)

Activity IPA Normal Crash Normal Crash

A - 5 4 500 600

B A 7 5 350 500

C A 8 5 800 920

D A 11 7 1,200 1,400

E B, C 6 4 600 700

F C 4 4 500 500

G D, F 7 5 700 1,000

H E, F 6 5 300 420

Solution

This simple project has five paths (see Figure 8.11). They are listed next, along
with their lengths in days:

5,12

19,25

13,19

B
7

E
6

H
6

6,13

19,25

13,19

25

0,5 5,13

A
5

C
8

PF

25

0.5 5,13 13,17 17,24

F
4

G
7

14,18 18,25

5,16

D
11

7,18

Figure 8.11 Precedence network for project in example 8.1—PF, project finish