Standards of Practice Course

1
Standards of Practice Course

• CPM Scheduling Lab

2
Activity Notation
Use for Manual Calculation
April, 2010
3
Sample
Notation
ES
EF
ID
LF
LS
D
FF
TF

• ES EFP 1

Subscripts S Successor P Predecessor
4
4
B
7
7
1

• EF ES D - 1

3
3
8
17
D
1
3
A
FS
FS
8
17
10
1
3
3

• LS LF - D 1

0
0
0
0
4
7
C
4
7
4

• TF LF - EF

• FF ESS - EF - 1

0
0

• LF LSS - 1

April, 2010
September, 2006
4
CMAA Formulas for Calculationfor Finish-to-Start
Activities

• ES EFP 1
• LS LF - D 1
• TF LF - EF

• EF ES D 1
• LF LSS 1
• FF ESS - EF - 1

April, 2010
September, 2006
5
CMAA Calculation Tips

1. Start by taking note of the relationships.
   Notice which are not finish-start, or which ones
   are finish-start but with a lag. (Formulas dont
   apply to Start-to-Start relationships or
   Finish-to-Finish relationships.)
2. Begin calculating on the first activity on the
   left side.
3. In CMAAs examples, the first activity begins on
   Day One. Not Day Zero.
4. Work towards the right, in an up and down motion,
   in strips (this is to avoid unnecessary
   iterations).

April, 2010
September, 2006
6
CMAA Calculation Tips

1. When working with a lag greater than 0, first
   calculate the link as if it had no lag. Then add
   the lag time.
2. When an activity has multiple predecessors, each
   predecessor must be evaluated in turn to
   determine the correct early start date for the
   successor. During the Forward pass, the greater
   (latest date) overrides.
3. The same concept holds true during the backward
   pass. For activities which have multiple
   successors, each successor must be evaluated to
   determine the correct late finish date for the
   preceding activity. During the backward pass,
   the lesser (earlier date) overrides.
4. The last activity has no successor, so the late
   date formulas dont apply. Assume for the last
   activity, EF LF END.

April, 2010
September, 2006
7
Exercise 1
Notation
ES
EF
ID
LF
LS
D
FF
TF

• ES EFP 1

Subscripts S Successor P Predecessor
4
B
1

• EF ES D - 1

D
1
3
A
FS
FS
10
3

• LS LF - D 1

C
4

• TF LF - EF

• FF ESS - EF - 1

• LF LSS - 1

April, 2010
September, 2006
8
Exercise 2, Part 1

• PART 1 Calculate a Baseline Schedule
• The AON logical network of a baseline schedule
  for a
• construction project is as shown in Exercise 2.
  Assume that for the last activity EFLFend of
  project.
• Required Answer all questions on network diagram
  only
• Calculate the ES, EF, LS, LF, and TF for each
  activity.
• What is the free float (FF) for activity E?
• What is the free float (FF) for activity F?
  Explain the difference in days between the FF and
  the TF for activity F.

April, 2010
September, 2006
9
Exercise 2, Part 1

• All relationships finish-start unless noted.

B
C
FS - 2
10
10
A
D
H
E
FS 2
10
5
5
5
F
G
SS 5
10
10
April, 2010
September, 2006
10
Exercise 2, Forward Path
A
B
FS - 2
C
FS 2
D
E
SS 5
F
G
H
April, 2010
September, 2006
11
Exercise 2, Backward Path
A
B
FS - 2
C
FS 2
D
E
SS 5
F
G
H
April, 2010
September, 2006
12
Exercise 2, Part 2

• PART 2 Calculating Progress on the Schedule
• At the end of the day on day 15, the following
  progress information was available
• Activity A started 2 days late, and was completed
  on time.
• Activity B started on time, and made progress as
  follows.
• Completed work in place 500 sq ft
• Remaining work quantity 500 sq ft

April, 2010
September, 2006
13
Exercise 2, Part 2

• PART 2, Continued
• Activity D started on day 14. Remaining duration
  required for completion is estimated to be 2
  days.
• The original duration for Activity E changed from
  5 days to 20 days.

April, 2010
September, 2006
14
Exercise 2, Part 2

• PART 2, Continued
• Required Answer all questions on network diagram
  only
• Based on the progress information available at
  end of day 15,
• Q1. Calculate actual start and finish dates for
  all activities in progress.
• Q2. Calculate the ES, EF, LS, LF, and TF for all
  other activities. Identify the critical Path.

April, 2010
September, 2006
15
Exercise 2, Part 2
Notation
Actual Start
AS
AF
AD
Actual Duration
ES
EF
ID
LF
LS
D
Actual Finish

• All relationships finish-start unless noted.

FF
TF
Dur RD if ADgt0 Dur RD if AD0 (activity has
not started)
B
C
FS - 2
10
10
A
D
H
E
FS 2
10
5
20
5
F
G
SS 5
10
10
April, 2010
September, 2006
16
Exercise 2, Forward Path
Data Date Day 16
A
B
FS - 2
C
FS 2
D
E
SS 5
F
G
H
April, 2010
September, 2006
17
Exercise 2, Backward Path
Data Date Day 16
A
B
FS - 2
C
FS 2
D
E
SS 5
F
G
H
April, 2010
September, 2006