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Redundant ties as basis for schedule rejection

3 replies [Last post]
Steve Eiden
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Joined: 16 Sep 2004
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Has anyone successfully countered the USACE's position on rejecting a schedule with redundant ties? My position is that there is constructive logic and preferential logic in a schedule and that both are legitimate. I don't think the corps specs refer specifically to redundant logic but their representatives are misinterpreting the language for their benefit. As far as I can see the justification for clearing redundant ties is to limit clutter and make it easier for Fuse to run risk analysis...I could care less about either of these and want the owner out of my schedule. Thoughts?

Replies

Rafael Davila
User offline. Last seen 40 min 13 sec ago. Offline
Joined: 1 Mar 2004
Posts: 5229

Mike,

In my example link 1-3 is driving, the following figure shows the links table a bit expanded as to show more attributes, it is driving and critical. If there was no lag then it could be declared redundant. 

 

 photo linksattributes_zps3bafc7d3.jpg

 

If activity 2 is delayed then link 2-3 will be driving, deppending on how the job progress either link can become driving.

When used for manual resource leveling or to define changes in preferential logic I would not declare them as redundant. Even when redundant they do no harm unless you create excessive redundancy, a bit of it wont do any harm. 

It surprises me the USACE have become so picky, looks like they got contaminated by the attitude of other USA agencies that get too much of their nose on the means (tools) and methods of the contractor, I advocate for a Free America.  I always want the owner out of my schedule unless it is a cost plus contract and he absorbs all schedule risk. 

I wonder if the Payment and Performance Bond can be executed when the owner gets too much of its nose on the contractor means and methods.  If I had such an owner I would inform the surety of what the owner is doing.

Best Regards,

Rafael

Mike Testro
User offline. Last seen 1 week 4 days ago. Offline
Joined: 14 Dec 2005
Posts: 4418

Hi Raphael & Steve

I would consider link 1 to 3 in your example as being Non Driving in Asta terminology.

Is that the same as Redundant?

If so they have a contribution in generating float and must be retained when adding progress and for delay analysis.

Best regards

Mike Testro

Rafael Davila
User offline. Last seen 40 min 13 sec ago. Offline
Joined: 1 Mar 2004
Posts: 5229

Steve,

I agree with you, maybe FUSE Risk Analysis engine is poor, otherwise why prohibit redundant logic, it does not harm.  It might be a dirty trick to promote sales of software that looks for redundant logic, to me an exercise that adds no real value, on the contrary, the exercise can be a source of errors.  

At times I wonder how safe are these software at identifying redundant logic.  In the following figure no link is redundant, if the software identifies link 1-3 as redundant you shall be better off without such crappy software.

 photo redundantlogic_zps5b9251e5.jpg

In addition very frequently those who do not believe in software resource leveling attempt to model resource dependencies with "soft" links and this procedure creates a lot of redundant occurrences. Although not my approach it is legitimate as well.

Rafael