1. Project Planning
By Phaik San Liew

2. Today objectives Recap from last block week lessons
Produce a network diagram.
Determine the critical path.
Make simple interpretation from the result obtained
Produce a link bar chart.
Compare both method

3. Activity on Node Method
Duration Time
Earliest Finishing Time Time (EFT)
Earliest Starting Time (EST)
Dependency Arrow
Activity ID
Latest Starting Time (LST)
Latest finishing Time (LFT)
Total float
Project Planning
Critical Path Method Practical Examples

4. Activity on Node Method
Preceding activity
Duration A / B C D
B,C
Steps 1: List or break down the activity 3 4
Steps 2: Work out the preceding activity 6 2
Steps 3: Determine the duration. B
Start A D
Finish C
Step 4: Develop the sequence
Step 5: Transfer the data

5. Activity on Node Method - 1st Pass
Go from left to right
We always start on day 0, the EST for task A is therefore 0
We then add the duration to the EST to get the EFT
The EFT then becomes the EST of the next step
These steps are then repeated until the network is complete
This give use the project duration 4 B 3 7 11 11
Start 3 A 3 2 D 9 11
Finish 6 C 3 9
If there is more than 1 EFT use the highest for the next step

6. Activity on Node Method – 2nd Pass
Go from Right to left
Take the LST from the finish node and put in to the LFT
To calculate the float take the EFT for the LFT
The LST is the float added to the EST
This is then completed until the all the nodes are done 4 B 3 7 11 11
Start 3 A 3 2 D 9 11
Finish 5 2 9 3 6 C 3 9 9 11
If there is more than 1 LST use the Lowest for the next step 11 11 3 9

7. Activity on Node Method – 2nd Pass
The last task is to identify the nodes with ‘zero’ float by highlighting the arrows red – This is the CRITICAL PATH 4 B 3 7 11 11
Start 3 A 3 2 D 9 11
Finish 5 2 9 3 6 C 3 9 9 11 11 11 3 9

8. Summary Tables
The information from the network diagram can then be used to create a summary table
Activity
Duration
Earliest Start Time
Latest Start Time
Earliest Finish Time
Latest Finish Time
Total Float A 3 B 4 5 7 9 2 C 6 D 11

9. Student Activity - Example 1a
Create the appropriate network diagram, determine the critical path and create a summary table
Activity
Preceding activity
Duration A / 5 B 8 C 7 D 4 E 2 F 6 G 12 H 9 J K

10. Student Activity - Example 1a
Step 1:
Draw the logic sequencing on the space provided
Step 2:
Transfer your answer to the network diagram form provided and start working on the duration
Step 3:
Work out the summary table.
(optional)

11. Student Activity - Example 1a
Sample answer 13 7 20 C 20 6 26 F 26 4 30 J
Start 5 A 5 8 13 B 13 4 17 D 14 1 18 17 12 29 G 18 1 30 30
Finish 13 2 15 E 17 4 19 15 9 24 H 19 4 28 24 2 26 K 28 4 30

12. Student Activity - Example 1a
Q1. What is the total project duration ?
Q2. Which is the critical path?
Q3. What happen to the project duration if activity 'C' is taking additional 2 days?
Q4. What happen to the project duration if activity 'D' is 1 day behind schedule?
Q5. Ignore all the above-mentioned possibility, Contractor E would like to start on 17th day, will you allow? Why?
Q6. What is the float for E, H and K? Will the total project duration be affected if each of E, H and K delay for 4 days one after another?

13. Student Activity - Example 1a
Day No.
Activity
Preceding Activity
Normal Time (day) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 A / B C F J D G E H K
Link Bar Chart

14. Link Bar Chart or PERT? Advantages of Bar Chart
Resources may be shown on the bar chart, which clearly relates labour, plant and subcontractor to the rate of working and helps the manager to see problems of continuity and waste.
Easily updated at weekly and monthly intervals for review purposes and progress reports.
applicable at all stages of the planning process: project planning, pre-tender, and pre-contract and contract planning
Simple format readily understood at all levels of management
Key milestone symbols may be introduced to highlight critical dates with regard to key contract stages, information requirements and as an aid to subcontractor and materials procurement.
Clearly mimics the construction sequence - the use of linking between bars facilitates the overlapping of related operations.
widely accepted in the construction industry, often being used to compare the planned and actual progress especially in progress meeting.

15. complex interrelationships cannot be clearly shown.
Link Bar Chart or PERT?
Disadvantages of Bar Chart
do not show dependency and therefore do not clearly indicate which operations directly relate to the successful completion of the project. This makes it difficult to apply management by exception
Logical links are used to overcome this problem but these can become confusing and difficult to interpret on complex projects.
complex interrelationships cannot be clearly shown.