Large Example

Figure 6.10 presents the task network for the large example. The top line of each box is an identifier for the task. The color relates to a specific resource. The numbers at the bottom of each box represent the task duration in days. The task durations have already been cut by 50%.

Lay out the critical-chain plan for this project.

The first step is to lay out the network. Figure 6.11 illustrates the project entered in the MS Project Gantt Chart view. Looking from left to right, note how the magenta (Mag) tasks A-1 and B-2 overlap. Then the blue resource tasks B-3, C-3, and D-3 overlap. It is easy to see that the critical path through this network is the top logic path, as it shows no gaps.

MS Project enables you to remove these contentions by resource leveling, as illustrated by Figure 6.12. Note that most chains now have gaps in them, making it impossible to define a critical path.

Next, you must identify the critical chain. Figure 6.13 illustrates the critical chain identified by the CCPM+ software. Observe how the chain jumps the logic

UJ M

ID

Task name

Duration

1 Ian 2 '00

|an 9,'00 ||an 16,'00

Ian 23,'00 ||an30,'00

Feb 6,'00 | Feb 13,'00

Feb 20 '00 | Feb 27,'00

Mar 5, '00

S | M| W| F

S | T | T | S | M| W| F

S | T | T | S | M| W| F

S | T | T | S | M| W| F

S | T 1 T| S | M| W| F

S1T|T|

1

1.1

15 days

Red

2

1.2

10 days

*

| Green

1

3

2.1

10 days

Blue

J

k

4

2.2

5 days

| Green

5

FB

8 days

1 1

6

3

15 days

| Mac

genta

1

7

PB

22 days

DI

llllllllllllllll

Illllllllllllll

Illllllllllllll

8

9

1.1

15 days

Red

10

FB

8 days

1 1 1

1

11

1.2

10 days

| Green

1

12

2.1

10 days

Blue

ZD

13

2.2

5 days

| Greer

1

14

3

15 days

| Mac

genta

1

15

PB

22 days

ih

Figure 6.8 The second resource resolution choice leads to the same lead time for the two choices of critical chain and completion on March 1 0, 2000.

Figure 6.8 The second resource resolution choice leads to the same lead time for the two choices of critical chain and completion on March 1 0, 2000.

Project complete

Figure 6.9 Small exercise.

C-6 Magenta 5

Figure 6.10 Large example. (Task times already reduced.)

Figure 6.10 Large example. (Task times already reduced.)

C-6 Magenta 5

A-6 Red 15

Project complete

Figure 6.11 Large example Gantt chart illustrates resource contention.
Figure 6.12 Resource contentions leveled.
Figure 6.13 Identifying a critical chain.

path several times. You can also see, by tracing backwards from the end of the project, that there are no gaps in the critical chain at this point, even though most logic paths have gaps in them.

Finally, inserting the project and feeding buffers completes the plan. Figure 6.14 illustrates the completed plan. In this case, we sized the project and feeding buffers as 50% of the preceding activity chain. This project requires three feeding buffers.

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Project Management Made Easy

Project Management Made Easy

What you need to know about… Project Management Made Easy! Project management consists of more than just a large building project and can encompass small projects as well. No matter what the size of your project, you need to have some sort of project management. How you manage your project has everything to do with its outcome.

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