Tips on using this forum..

(1) Explain your problem, don't simply post "This isn't working". What were you doing when you faced the problem? What have you tried to resolve - did you look for a solution using "Search" ? Has it happened just once or several times?

(2) It's also good to get feedback when a solution is found, return to the original post to explain how it was resolved so that more people can also use the results.

Primavera - Relationship between activity

6 replies [Last post]
Jithin Kambhikanam
User offline. Last seen 2 weeks 1 day ago. Offline

Hello Everyone,

Hope everyone is in good health. 

A doubt. I have received comments on a schedule,

  • The use of Finish-start relationship is prefered (FS). Avoid as much possibe use of Finish-Finish (FF) plus lags and start -start (SS) plus lags relationship between activities.
  • FF relationship do not provide visiblity and clarity regarding schedule logics and drivers fr key activity.

Is the above statement right ?

Moreover in my schedule I have no open end activity, each activity will either have FF or FS or SS relationship with a lag. So would ac activity be considred "Opend End" if it the predecedosr/sucessor rlationship is having only FF or SS ?

Is only FS relation is considred as Closed end ?

 

Stay safe.

Thanks 

Jithin

Replies

Rafael Davila
User offline. Last seen 14 hours 22 min ago. Offline
Joined: 1 Mar 2004
Posts: 4907

Open-Ends00

Open-Ends01

hoover images and click

I suggest creating filters for dangling activities.

dangling-activities-filters

Best Regards, Rafael

Rafael Davila
User offline. Last seen 14 hours 22 min ago. Offline
Joined: 1 Mar 2004
Posts: 4907
Rafael Davila
User offline. Last seen 14 hours 22 min ago. Offline
Joined: 1 Mar 2004
Posts: 4907

The risks of splitting activities that shall be executed continuously can be far more dangerous than pretending concurrent logic does not exists. This is specially true if your model is to apply resource constraints, it might spread apart the segments of an activity that shall be continuous. In such case use of SS(+lag) in combination to FF(+lag) relationships will make a better model.

Best Regards, Rafael

Zoltan Palffy
User offline. Last seen 2 days 21 hours ago. Offline
Joined: 13 Jul 2009
Posts: 2773
Groups: None

technically a activity withonly a SS relationship would be open ended because you are only tying the start of it to something not the finsh of it.

 so the solution would be make it a compound relationship and have both a SS and a FF to the same successor. 

if you give me your email I can send you a pdf on why to use the compund relationsh and what can happen if you only use a SS relationship

Alexandre Faulx-B...
User offline. Last seen 1 week 1 day ago. Offline
Joined: 20 Jan 2003
Posts: 1320

Hello Jithin,

absolutely, this statement is right, every paragraph in the statement is right;

to answer your second question: an activity is open-end when the activity has no successor, either FS or FF; lag or lead has nothing to do with that

Alexandre 

Alexandre Faulx-B...
User offline. Last seen 1 week 1 day ago. Offline
Joined: 20 Jan 2003
Posts: 1320

Hello Jithin,

absolutely, this statement is right, every paragraph in the statement is right;

to answer your second question: an activity is open-end when the activity has no successor, either FS or FF; lag or lead has nothing to do with that

Alexandre