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Dear friends and colleagues,
I have the below issue:
There is a task A that lasts, for example, 8 working days as well as the taks B that lasts 7 working days.
The task A can not be completed if a part of the task B hasn’t be finished first. The duration of partial completion of task B is 2 working days.
The task A can start any time but during its evolution needs the information of the partial completion of task B in order to continue its evolution and be completed.
How can this interdependence be represented in a Gantt Chart?
Thank you in advance for your help.
Stergios Kokkoris
Civil Engineer
You have a couple of constraints that make setup a bit difficult. You could split both tasks into two tasks each (Task A1, Task A2, Task B1, Task B2) and then setup appropriate predecessors. You may also need a FF predecessor type. Of course there is a balance between complicating task setup and proper team communication. Just saying if that is the only task in question.
Stergios
Try making the dependency relationship Start-Start and also add a positive Lag value. Meaning, you could link Task B as the predecessor to Task A the successor with a Start Start relationship and add a +2D (plus two days) Lag value. This essentially says both A and B can start at the same time but delays the scheduled start of A (the successor) 2 days.
Just a thought.
Hope that helps.
Stergios, This is a trick question, and you’ve left out a key piece of information. You’ve said that A can start at any time but needs 2 days of progress on B before it can “continue its evolution and be completed.” How much of its “evolution” depends on the information from B? In the simplest case, A can’t finish until 2 days after B starts. I.e. B>SF+2>A. This (two uninterruptible tasks with SF relationship) is a situation that virtually never happens in real life. I’d avoid it. Better follow Larry’s advice and break the tasks up. E.g. two alternatives:
1 Alt 1 8 days
2 SMS 1 0 days
3 Task A 8 days 4SF+2 days,2
4 Task B 7 days 2
5 Alt 2 8 days
6 SMS 2 0 days
7 Task A Execution 8 days 6
8 Task A Completion 0 days 7,9
9 Task B Phase 1 2 days 6
10 Task B Phase 2 5 days 9
Good luck, tom
Dear Lary, Daryl, and Thomas thank you very much for your contribution. I appreciate your time and effort.
Warmest regards
Stergios Kokkoris