Zhang,

Once the programme is resource loaded, practically speaking, the programme has no float. Because, the moment you try to use the float, the allocation of resource will change from what was there in the target. Any variation from the target is a Variation and can become a claim. Apart from a few real physical relationship (like concrete pouring after formwork), quite a lot of other links in the programme are resource links (like this crew goes to that work once it is complete).

It’s really difficult to do such kind of assessment.

If the client caused a critical delay ( a delay on critical path as shown on the schedule approved by client), the contractor has the right to get EOT.

the duration of a task depends on resource/productivity...,12 days or 15 days which is correct? there’s no answer.

if the client apporved this 15days duration, then later he has no right to ask contractor to shorten the duration for free.

If the client caused a delay on no-critical task, and make critical or near critical, the contractor still have the change for EOT. (to keep the original critical path on schedule, the contractor need more resource,otherwise the schedule will be delayed). But it’s difficult to prove it, unless the contractor has a good schedule(clear logic, full resource loaded) and detail actual record. Generally the con tractor will not win.