(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.
Hi all,I have two small issues with logical relationships, I hope you will get me out of this. The situation is as follows: I issue (Priliminary Clearance):The Project is a 80 Km Highway.I have two activities :A1) Clearing and Grubbing; andA2) Constructing Embankment ;both resource driven and independent teams. I have divided the project length into 5km sections (say S1, S2,…) for the sake of tracking.A1 requires 5days time to be complete and A2 requires 18days time to be completeA2 can start 3days after A1 starts (i.e., SS+3D)As A2 is the Critical Activity in my programme, S2A2 starts immediately after the completion of S1A2. However, I want S2A1 to start just 3days before the start of S2A2 but not after the completion of S1A1. How should I logically relate S2A2 and S2A1 now? II Issue (Deferred Commencement) : I want to commence the construction of a Maintenance office after two years and can be done quiet independently of other project works. Without losing the integrity of the schedule how can I logically relate this commencement to the project start date. Kindly help. Thanks in advance satish
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Hi Satish
You are welcome - any time.
Best regards
Mike Testro
Thank you very much mike.
Hi Sasish
Set it ALAP.
Best regards
Mike Testro
Hi Mike,
I understood your intention of using shorter section; when i said i was using the same technique you told but with 5 km sections, i forgot to tell i was using a ss relation but not an FS bcoz FS will not be practicable with longer sections, i understand i am wrong. SS is not correct due to distorted logic.
But if such a case as I said (C&G to be done just before embankment) araised what is the best way of depicting it without compromising both contract condition and relationship logic?
Thank you
Hi Satish
If done correctly the grubbing will appear as a continuous set of tasks with a gap of available float before the next longer tasks.
This represents the correct work flow - showing avaliable float.
The big problem with a SS Lead Lag link is that when progress goes beyond the link all downstream logic is lost.
You will have better control using the shorter sections.
Best regards
Mike Testro.
Dear Mike thankyou for taking your valuble time. I am using MSP. I have done it in a similar fashion as you said. but all the clearing and Grubbing activities are far from the succeeding activities except the first section. How to avoid the gap??
even if i take 500m :
Date 05.08.2013; (say S1A1) C&G is going to take 4hrs, where as embankment S1A2 will take 4days.
C&G S2A1 will commence after S1A1 on 05.08.2013, but embankment S2A2 will commence on 09.08.2013; the gap between C&G and Embankment is increasing which I have to avoid as per contract.
Further, I cannot FS S2A1 with S1A2 as they are resource independent.
Notation used: S1A1 means section 1 Activity 1; similarly SiAj means Section i and Activity j
Regards,
K. Satish Kumar
Hi Satish
I suspect that you are using P6 software and that is not suitable for linear projects such as roadworks.
The only way to make any sense of it is to split it down into smaller lengths and put every successive task in a FS cascade for each length - say 500.00m.
Then cross link every task - this will give you a rudimentary "Time Chain" schedule.
It is not complex even in P6.
Set up one cascade and sumarise it from Lineage 000.00 to (say) 500.00 then copy paste for as many as are required - about 160 summaries?.
Then filter each task and use the multi link to select and link each task FS - you now have a horizontal and vertical logic matrix - the same used in Tilos or Vico.
This should take about 2 hours of a skilled P6 operators time.
You can now apply particular logic for traffic management and any structures deducting task links as required.
Regarding the arisings from the old road? Are you salvaging it for fill? If so that needs to be built into your schedule.
Best regards
Mike Testro
Thanks a lot mike for your reply- issue 2 seems resolved.
As far as the Issue1 is concerned there are many other activities in a 5 Km stretch which I have ignored for the sake of simplicity and the activities are also more time consuming. even if I make the stretch smaller I will not be able to resolve the issue as C&G is going to take even less time when compared to other succeeding activities. So, all I want to do is I want to retain it in the schedule but to commence just before the embankment activity. It is also stated in the contract that C&G shall be done just prior to the commencement of embankment activity to avoid erosion of top soil !-an Environmental issue.
I have an existing carriageway also. If I take 5 km, I will have to depict 32 sections with about 10 activities per section.
i.e., 80/5=16 sections; Sequence: Strengthen and widen the existing section eccentrically to one side then take up one half width of it (say LHS) and complete it and then divert traffic onto the new section and construct/improve the existing section. (16 LHS sections and 16 RHS sections) making total of 32 sections. Further, I have to ensure that I will complete all the culverts/Bridges etc., in that section before the wearing coat is takenup.
Now, if I make it even smaller It is going to be very complex. Do you agree or not??
Hi Satish
Issue 1.
Break your project up into smaller dstances (5km is too long) so that Clearance and Grubbing is a 3 day task and then use a FS link to Embankment for the same distance.
The critical path will then go through Embankment.
Issue 2.
Set up a calendar with a 2 year non work period from day 1 and apply it to the Maintenance section.
Then set up your logic as normal.
Best regards
Mike Testro
Email: PPadmin@planningplanet.com
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