logic in premavera p3 (Urgent please )

Mohammed,



The answer to your query depends on what you hope to achieve from your plan.



If you want the plan to reflect how you intend to execute the works because you want the staff/contractors to follow the plan then you need to decide if you want the blockwork to commence at the 20% mark (and run out of slab after 1 day or assign a small crew so they never catch up with the slab) or delay until 4 days before the slab is complete and hit it with a full crew. You could also divide the area into 5 logical areas and do 1 day’s blockwork on completion of each area. There is no right answer but you need to make/get a decision.



If you are producing a plan to attempt to put things on the critical path to assist in substantiating delays then the longer blockwork activity will help bury the float.



I would try to break it into areas or segments/sectors you build a better model that will respond to issues that they arise e.g. if you have a unexpected condition occur that impacts only a small section of the slab and delays it the true impact of the delay is easier to assertain and removes the need for non FS relationships and lags.

It May sound like not as easy but I have found it is always easier to show Milestones Example steel contractor to give access to Civil Contractor Etc.



This way it is easy.



But what is strange for me is that you are not using any props.

Also you dont say anything about Curing Time.



Cheers

Relationship should ideally be (FS) to obtain the best/accurate Critical path. But depending on the stage of the project/ details most of the times it is not possible to assign FS relationship & hence the uncertainity of SS/FF FS (with - lag) arise.

Simple eg is Piping Prefab & Erection. At Macro level (Levels 1,2,3) it is just not possible to have a FS relationship unless we go deep into the last possible activity.

The relation can be SS with some lag , FF with some lag (???). Not sure of the quantities/ methods etc)

We are not sure of the lags either.

SS/FF relationships (both) give a flexibility in defining relationships, but FS (with - lag) is again a deterministic which may not hold true while updating (you may require to change lag while updating)

This is better understood while using Pertmaster for risk analysis of schedules wherin lags are convereted into tasks.

In such cases it is better to have both SS & FF with lags for more accuracy in schedules.

First objective of linking the actvities, to show the proper dependencies in schedule, it is not for showing your negative and positive lags. For example you added SS relationship in two activity with some lag, this does not show how their completion are dependent. If you don’t want to show negative lag, try to break down the activity further.

Hellow Rolyn,



Is it true that all activities should have either a FS with a positive lag or a (SS and FF) for every activity OR it may affect the critical path.



Regards



Sunil

Sorry the display is not correctly posted

I will try again



MMMMMMMMMMMMMMMMMMMMMMMMMMMM

ss

BBBBBBB(1)--------------ff(+4)

-------BBBBBBBB(2)

------------BBBBBBBBBBBBBBBBBBBBBB(L)

I agree try to avoid using negative relationship

use SS to link the first area of mezz level slad finish and ff with the last block work



MMMMMMMMMMMMMMMMMMMMMMMMMMMM

ss

BBBBBBB(1) ff(+4)

BBBBBBBB(2)

BBBBBBBBBBBBBBBBBBBBBB(L)

good day...

if there is no obstruction on the grade level, you can link the blockwork activity directly to the mezzanine level slab using FS relationship.

Use the combination of SS & FF relationship instead of FS with negative lag.