The document discusses the development of networks for project planning. It describes the key steps as: 1) Breaking down the project into activities through examining the objectives and identifying difficulties, assistance needed, and safeguards. 2) Sequencing and grouping related activities. 3) Locating the events on paper to show initial relationships between activities. 4) Drawing the network by connecting related activities with arrows. 5) Checking the network for accuracy and making revisions if needed.

1. Construction Technology &
Management
Dr. Abhishek Jindal
Development of Network

2. Development of Network
Introduction
Planning for Network Construction
Methods of Network Construction
Steps in Development of Network
Work Breakdown Structure
Hierarchies
Practice Problems

3. Development of Network - Introduction
● Project Planning - Network Techniques (CPM / PERT) - well
specified or clearly defined objectives / Activities.
● Basic principles of Network and terminologies - Activity,
event, dummy, rules etc.
● Concept of breaking down a project into activities in
order to draw - network.
● Breakdown necessity - for basic calculations required for
scheduling and analysis.

4. Development of Network - Planning for Network Construction
Networks could be constructed by following plannings:
1. Forward Planning
Planner starts from initial event & builds up events & activities
logically & sequentially until end event is reached.
1. Backward Planning
Planner starts with end event and arranges the events & activities until
the initial event is reached.
1. Combined Planning
Combination of both forward and backward planning is followed.

5. Development of Network - Modes of Network Construction
Two modes:
Event Oriented Diagrams
PERT users - emphasis on events of project. First select the events to be
included in plan, focus on start and completion of event rather than activity.
Activity Oriented Diagrams
CPM users - emphasis on activities of project. Activities are arranged in
sequential & logical order. A description of activity is written on arrow.

6. Development of Network - Steps in Development of Network
Steps:
1. Objective
2. Plan Breakdown
3. Sequencing
4. Development
5. Drawing
6. Check
7. Redraw and Introduce
8. Number

7. Development of Network - Steps in Development of Network
Objective
● Specifies the task to be undertaken and policy of its execution.
● This specification defines the project and determines the way in which it
is to be carried out.
Example: Specification for a lathe installation project.
A new lathe is to be installed at a location by removing the existing machine
to clear the floor. Existing machine is to be disposed off and the complete
installation is to be tested.

8. Development of Network - Steps in Development of Network
Plan Breakdown
● After establishing - objective - planner has to adopt either forward /
backward or mixed planning.
● List of activities or jobs to be performed to achieve the task and stages
in project execution.
● To obtain the list of activities or events the specification / objective
has to be examined under three headings:
● What are the difficulties that have to be overcome
● What facilities will assist in the removal or circumvention of the obstacles
● What safeguards will have to be taken in using the facilities
● The result of the examination will create a list of activities and / or
events.

9. Development of Network - Steps in Development of Network
Plan Breakdown
Example: For lathe installation project, plan breakdown is done by examining
specifications under above mentioned questions:
(a)What is the way in reaching the objective?
New lathe is to be purchased. Existing machine is to be removed and
disposed off.
(a)What is the help available?
Power supply for testing.
Finance for purchasing the lathe.
Implements for removal of existing machine.
Disposal facilities.
(a)What safeguards are necessary?
Removal of existing machinery is necessary to clear off the site for
installation. Also installation of power supply is necessary.

10. Development of Network - Steps in Development of Network
Following list is obtained:

11. Development of Network - Steps in Development of Network
Sequencing
● In second step - list of activities and events necessary for completion of
project.
● This general list is to be reviewed so that in each of the main group,
those with definite similarities can be put in suitable sub-groups.

12. Development of Network - Steps in Development of Network
Sequencing
Marshalled List

13. Development of Network - Steps in Development of Network
Development
● Events listed above are required to be located on paper.
● Events should be located in such a way that they represent initial picture
of relation amongst them.
● This relationship results from proposed use of manpower, money, material
and other resources during a particular period of time.
● Questions regarding sequence:

14. Development of Network - Steps in Development of Network
Drawing
● Events having close and direct relationship are joined to each other by
arrows representing activities.
● Questions regarding sequence of activities:

15. Development of Network - Steps in Development of Network
Check
● The diagram is checked with respect to :
Content
Sequence
Sense
Degree of Detail
E/A ratio = Total no. of events / Total no. of activities
For a good network E/A ratio should be between 1 and 1.6.

16. Development of Network - Steps in Development of Network
Redraw and Introduce
● Errors found in previous steps are removed, and diagram is redrawn by
introducing dummies if required.

17. Development of Network - Steps in Development of Network
Number
● After having drawn the final network, the events are numbered using
FUlkerson’s rule.

18. Development of Network - Work Breakdown Structure
Plan breakdown to identify the activities and events necessary for completion
of project.
Example:
House Construction Project

19. Development of Network - Work Breakdown Structure

20. Development of Network - Work Breakdown Structure

21. Development of Network - Hierarchies
Large and complex network - more than 200-500 operations.
If all operations represented by 1 network - clumsy.
Use a hierarchy or family of networks of increasing
details.

22. Development of Network - Practice Problem

23. Development of Network - Practice Problem
Breakdown

24. Development of Network - Practice Problem

25. Development of Network - Practice Problem

26. END