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Critical Path

12 replies [Last post]
Mon, 2007-04-02 05:49
Jonathan Ward
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Wondered if you could help me,, I have a schedule in P3 with a lot of activities, is there a way I can run a filter to view only crital activities/critical path?
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Replies

Thu, 2007-06-07 02:49
#1
A D
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Nice paper on As-Built Critical Path (ABCP)

http://www.planningengineers.org/publications/papers.aspx

Cheers,

Raviraj A Bhedase
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Tue, 2007-06-05 09:29
#2
Ad Ben
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I don’t think that Overtime is the problem. I have project that has 14 structures on it. Not including the on & off site utilities. I have a critical path that runs through 2 of them. They all have to be done but 2 have the largest amount of activities in them and they both are on a Critical path to keep both of them moving. There are some off-site activity’s that involve getting power to the site. This one is part of a change order and the owner wants me to take it off of CP so that he can say we don’t get extra time to do the extra work.
I think this is BS.
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Tue, 2007-06-05 02:30
#3
Ashraf Jahangeer
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Dear Hannes,

You are very correct in saying that situation changes all the time as regards to critical path and floats all the time but if the critical path is identified carefully chance are it will remain more or less critical all through the life cycle of project.

As I understand Critical Path Analysis is the core of schedule control. Critical activities and paths are defined by the project management team based on the past experience and present constraints rather than just by running P3.


Regards,


Ashraf
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Tue, 2007-06-05 02:17
#4
A D
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Ashraf,

It has nothing to do with the number of critical paths.

But, if any activity has been scheduled with overtime in-built, one should not do that and if overtime activity is on a critical path, then it is not supposed to be. (No harm in giving overtime, but always beneficial as a planner not to schedule with overtime).

Just a advise.

Cheers,

Raviraj
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Tue, 2007-06-05 02:15
#5
Hannes de Bruyne
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Some remarks to Critical paths:
Primavera is working according to "Critical Path METHOD". This does not mean that a critical path is so important as discussions make believe. If you use your time and resources in a proper way, you will have a critical PROJECT. (or a waste of resources) Of course one path ist the longest, but in most projects this can change very easy to a total different path, so don’t focus to much on it.
An other thing is, if you look at the discussion "Float in program.. Whom does it belong to?" Actually this question cannot been answered so easily - so take care that a schedule is linked in such a proper way that no float is clearly vissible. And if there is no float - there will be no critical path. So do not show too much critical path as this will mean that somebody wants to take your float!
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Tue, 2007-06-05 02:14
#6
Ashraf Jahangeer
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Ravi,

What is the point you are trying to make?

What has working overtime to do with having a number of critical paths in the project network?

Regards,

Ashraf
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Tue, 2007-06-05 02:00
#7
A D
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Hi Ben,

Do take care that, dont schedule a project so that overtime is required to complete it, since if probelsm are encountered, it may not be possible to work more overtime to solve them.

Adjusting the resources is not always possible. Applying overtime often increases errors, leading to rework,
which may mean that you don’t get the job done any faster than if you had simply worked a normal schedule.

Further, there is always a point of diminishing returns when you add bodies to a task. At some point the workers just get in one another’s way, actually slowing work down rather than speeding it. Overtime should be kept in reserve in case it is needed to resolve problems, and it is never a good idea to schedule a project so that overtime needs to be worked just to meet the original schedule.

Cheers,

Raviraj A Bhedase
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Mon, 2007-06-04 23:22
#8
Ashraf Jahangeer
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Hi Ben,

You are being told correctly as "you should not have too many critical paths on your schedule".

Theoratically you are correct that in big complex networks we can have a number of longest path or zero TF paths. This however is something mechanical and the role of project management team in general and the planning engineer in particular is to study the network closely and identify the critical activities which really have the potential to delay the project and keep a tight focus on their progress.

In absence of a clearly identified critical path and having lots of critical activites will lead to loosing focus and also will have less or no control over all of them. So usually we adjust our network and keep one critical path and then there are two or three more which we call near criticcal paths.

Regards,

Ashraf
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Mon, 2007-06-04 16:31
#9
Ad Ben
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Sorry if this is off subject. I am being told that I can not have "To many multiple paths on my critical path"
Does anyone have a stance on this subject? What constitutes a critical path other than float or path??
Why can’t there be several paths that all come down to Substantial completion?
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Mon, 2007-04-02 13:44
#10
Tom Kavanaugh
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There is a field in activity view called critical that has a yes or no value. Depending on the way you have chosen to calculate (longest path or least float). In Version 5 you can calcuate multiple float paths to determine near critical paths. Bottom line is you can create a filter that keys on the "critical" field.
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Mon, 2007-04-02 06:52
#11
Tom Barnard
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Failing that you could filter on Longest Path EQ Yes
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Mon, 2007-04-02 06:16
#12
Mark Chapman
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You should find a filter already there called "near critical activities". Or create your own TF<1 will select all critical activities.
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