Adding to activity duration vs Lag

Hi D

You creat a lead lag BUT it has to have a 24/7 calendar on it.

The drawback is that when the lag ends in a holiday period you lose all up stream criticality.

I have yet to find a way round this problem

Best regards

Mike Testro

there are many options here 

you inherently created a problem here whne you created a 4 day pour. It would have been best to create 4 seperate activities with 4 seperate cure activities. The problem that you have is that the pour on day 1 of the 4 days activity starts to cure on the second day of the pour and the cure from the pour on the 4th day does not start until the 5th day. So what you are doing is shorting yourself 3 days of whne you can get on that 1st poured area becasue you are waiting until 7 days after the last pour and not 7 days after the 1st pour on day 1.

option #1

after the pour make a 7 days curing actvity and make sure to put the curing activity on a 7 day calendar.

You could alwasy do a 3 day break and see if you have enough strength to get on pour after 3 days at least for what you poured on day 1.

When you use lags they become problems becasue there is not an explanation of what the lag is thast why it is better to create a seperate activity.

Hi Zoltan

You can give the link a category and a different colour and put the label in the legend.

Also if you are erecting a concrete slab you cannot take the early day forms down as it would endengaer the stability - particularly if it is poured checker pattern.

Otherwise you are quite correct that insitu concrete should be broken down into 1 day pours.

Best regards

Mike Testro

Sorry for any confusion. This is not a 4 day pour and the schedule is not to the level that requries different activities for forms, rebar, pour, wreck forms, etc. It is simply a single activity to pour a foundation. In this particular situation the activity is done once the concrete is poured and the wrecking of the forms will just happen. I wasn't sure if the lag would impact the critical path or the float and why it was being requested to be done that way. I would prefer the activity, the lag, then the activity of erecting steel. Bottom line is the steel must wait 7 days following the pour regardless. So weather its a 7 day activity that is progressed daily or a lag then I dont see why other than preference it would impact anything. Thats what I am trying to understand.

Hi D

Your question has been answered below but I would question why your task is not broken down into trade sectione. The curing lag has to be between pouring and striking formwork. Without that break down it can't be done properly. The other link is backfill trenches after formwork - you need a stable platform for the steel erection. Also where do the drains and floor slab fit in? Do you come back after the props to 1st floor are out and work underneath?

You need to think it through properly.

Best regards

Mike Testro