Basic Networks - Construction Project Scheduling and Control - page 24

DEFINITION AND INTRODUCTION
A network is a logical and chronological, graphic representation of the activities (and
events) composing a project. Network diagrams are basically of two types: arrow net-
works and node networks. Arrow networks were more popular in the 1960s and
1970s, and then precedence diagrams (an advanced form of node diagrams) became
the choice for network scheduling.
Network scheduling has revolutionized the management of construction projects.
It has provided management with a more objective and scientific methodology than
simply relying completely on the project manager's experience and personal skills.

ARROW NETWORKS
Arrow networks are also called the arrow diagramming method (ADM) , activity on
arrow (AOA) network ,orthe I-J method (because activities are defined by the from
node, I, and the to node, J). In this topic, we use the term arrow networks . Throughout
this chapter, you will find seven examples of arrow networks.

Example 3.1

Draw the arrow network for the project given next.

IPA a Activity

A -

B A

C A

D B

E C, D

a Immediately preceding activity.

Solution

Figure 3.1 Solution for example 3.1: a simple arrow network