Calculation Procedure:
- Identify the predecessor(s) of each activity; tabulate results
The critical-path method (CPM) offers a systematic means of scheduling activities in a
project and analyzing the consequences of departures from the schedule. The procedure
consists of devising a logical concatenation of activities after ascertaining the relation-
ships that exist among them. For example, activities D and E, Table 16, are independent
of each other and therefore may be performed concurrently. But activities D and F are se-
quentially related—F cannot commence until D is finished. Thus, D is the immediate
predecessor of F. Using these principles, list the related activities as shown in Table 17.
TABLE 16. Project Activities
Estimated
duration,
Mark Activity days
A Clear site 4
B Survey and lay out site 3
C Rough grade 3
D Excavate for sewer 8
E Excavate for electrical manholes 1
F Install sewer and backfill 4
G Install electrical manholes 6
H Install overhead pole line 6
I Install electrical duct bank 4
J Pull in power feeder 5
K Construct foundations for water tank 3
L Erect water tank 8
M Install piping and valves for water tank 12
N Drill well 14
O Install well pump 2
P Install underground water piping 9
Q Connect all piping 2
TABLE 1 7. Related CPM Activities
Activity Predecessor Activity Predecessor
B A J H and I
CB KC
DC LK
E C M L
FD NC
GE ON
HC PO
I F and G Q M and P
