Network planning
Download
1 / 13

Network planning - PowerPoint PPT Presentation


  • 67 Views
  • Uploaded on

Network planning. Learning objectives After these lectures you should be able to: Produce and analyse activities networks Calculate earliest and latest start and finishing times for activities Calculate activity floats and determine the critical path(s) through a network

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' Network planning' - yuli-wiggins


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Network planning

Network planning

Learning objectives

After these lectures you should be able to:

Produce and analyse activities networks

Calculate earliest and latest start and finishing times

for activities

Calculate activity floats and determine the critical

path(s) through a network

- Update networks as new information becomes available


PDM

Footings/1 wk Brickwork/3 wks Roof/ 2 wks

Landscape/1 wk Fence/1 wk


A

ES EF

t

LS LF

TF FF

A = Activity description, i.e. ‘Brickwork’

t = Duration (usually in work days)

ES = Earliest Start

EF = Earliest Finish

LS = Latest Start

LF = Latest Finish

TF = Total Float

FF = Free Float


Network analysis
Network analysis

Forward pass

0 1 1 4 4 6 6 8

A/1 B/3 D/2 F/2

1 1.5 1.5 2

C/0.5 D/0.5

ES EF NOTE: ES for the first activity is ‘0’, not ‘1’!

Name/Duration


Network analysis1
Network analysis

Backward pass

0 1 1 4 4 6 6 8

A/1 B/3 D/2 F/2

0 1 1 4 4 6 6 8

1 1.5 1.5 2

C/0.5 D/0.5

5 5.5 5.5 6

ES EF NOTE: The backward pass starts with the same

Name/Duration LF value as the last EF for the final activity

LS LF


Activity
Activity

Draw an PDM network for this project. Then do a forward and backward pass.

Activity Duration Depends on

A 5 None

B 5 A

C 12 A

D 3 C

E 6 B and 2/3 of C

F 8 B and 2/3 of C

G 14 A

H 5 D, E, F and G


Solution 13 21

F/8

13 21

0 5 5 10 13 19

A/5 B/5 E/6

0 5 8 13 15 21

5 13 13 17 17 20 21 26

C1/8 C2/4 D/3 H/5

5 13 14 18 18 21 21 26

5 19

G/14

7 21


Development of a network
Development of a network

Level 1

Level 2

Level 3

Final


Activity float
Activity Float

Critical activities: Have no float and are therefore fixed in time.

ES = LS and EF = LF

Total Float (TF): The amount of time that an activity can be delayed,

without that affecting the project completion time.

TF = LF – EF = LS – ES

Free Float (FF): The amount of time an activity can be delayed, without

that affecting the start of any following activity.

FF = ES(any following activity) – EF


13 21

F/8

13 21

0 5 5 10 13 19

A/5 B/5 E/6

0 5 8 13 15 21

5 13 13 17 17 20 21 26

C1/8 C2/4 D/3 H/5

5 13 14 18 18 21 21 26

5 19

G/14

7 21

Determine the Critical Paths(s) and all activity floats!


Activity TF FF Critical? 13 21

A 0 0 Yes

B 3 3

C1 0 0 Yes

C2 1 0

D 1 1

E 2 2

F 0 0 Yes

G 2 2

H 0 0 Yes

Critical Path = A - C1 - F - H


13 21

F/8

13 21

0 5 5 10 13 19

A/5 B/5 E/6

0 5 8 13 15 21

5 13 13 17 17 20 21 26

C1/8 C2/4 D/3 H/5

5 13 14 18 18 21 21 26

5 19

G/14

7 21

Critical Path (A – C1 – F – H) highlighted in network


Tutorial: Critical Path Method (CPM) 13 21

Carry out a critical path analysis for the following project in order to determine the total completion time for the project and the critical activities. Illustrate the critical path(s) in the CPM network. Calculate and list the Total and Free floats for all activities.

Activity Duration Depends on activity

A 3 weeks -

B 2 -

C 5 A

D 6 A and B

E 4 Half of D

F 4 C

G 5 D

H 8 C and E

I 9 D

J 6 I and H

K 18 B

L 4 K


ad