Monday, November 28, 2011

Project Schedule Network Diagram

The project schedule network diagram is a visual representation of the activities in a project and their inter-dependency. There are two common approaches to build a network diagram. The first approach is the Precedence Diagramming Method (PDM) which is also called Activity-On-Node (AON) (Figure 1).


Figure 1  Precedence Diagramming Method Example


In this network diagram, the activities are represented by boxes (node) and the logical relationships between the activities are presented by arrows. PDM allows the use of the four types of relationships that are finish-to-start (FS), finish-to-finish (FF), start-to-start (SS), and start-to-finish (SF). Figure 2 shows the representation of these different relationships. This approach is the most common one and supported by major scheduling software such as Primavera and MS Project. 


Figure 2 Relationship Representation in PDM

The second type is the Activity-On-Arrow (AOA) as shown in Figure 3. In this network diagram, the activities are represented by an arrow and connected by nodes. The nodes represent an event which could be the start or completion of an activity. Finish-to-start is the only relationship that can be used to express the dependency between activities when using the AOA approach. Sometimes it is necessary to use a dummy activity, which is an activity that has no time, to maintain the logical relationships in an AOA network. 


Figure 3 Activity On Arrow Example




If you have any questions, please do not hesitate to ask.
In future posts I will talk about the logical relationships between activities, how to construct an AOA network, and finding the critical path.

9 comments:

Anonymous said...

Hello,

In Figure 3, are B and G Finish to Finish (FF)

Do 3 and 7 represent the same date

Please confirm, thank you.

Mohammed Mawlana said...

Hello

Finish-to-start is the only relationship that can be used to express the dependency between activities when using the AOA approach. Hence, B & G are Finish-to start (FS).
3 & 7 does not represent the same date.

Hope I answered your question.

Evan said...

Is this a AON network diagram. What is the software you use to draw these for your blog posts? I want to know a online network diagram software that I want to use.

Mohammed Mawlana said...

Figure 1 is an AON network diagram. I used Microsoft Visio to draw them which you can download a trail version from Microsoft's website.

Unknown said...

We studied your blog and it is very nice. We found it really interesting and meaningful. We would like to visit it again.
We generally works with Project Management Software to make a plan of constructing and designing projects. Visit our page for more information.

sofianan said...

Thanks For Your valuable posting, it was very informative.I am working in Construction erp software in chennaiIf You need any more information kindly make me call to this number 44 45 07 8222.

Swethagauri said...

Nice blog has been shared by you. it will be really helpful to many peoples who are all working under the technology. Thank you for sharing this blog.
nebosh course in chennai

Anonymous said...

This blog is very informative thanks for sharing and keep on posting .#CONSTRUCTION COURSE IN DUBAI

Singhal Industries said...

I recently came across this Tree guard net and I’m really impressed with its features! The HDPE material looks durable and should provide excellent protection for young trees against animals and harsh weather. Plus, its design allows for good airflow while preventing damage. I’m considering using it in my garden to ensure my saplings thrive. Has anyone else tried this product? I’d love to hear about your experiences!

Post a Comment

Related Posts Plugin for WordPress, Blogger...