scopeeconomics
Follow a small activity network and explain the conditions behind its dates.
A schedule connects activities through relationships and durations. Begin with the work sequence: what must finish before another activity can start, which tasks can run in parallel and what conditions affect the durations. A bar chart without sound logic can suggest a finish date that the work cannot achieve.
In the example, mobilisation precedes both civil work and procurement. Installation needs both branches to finish. The branch with the later finish governs the installation start. Adding every activity duration would be wrong because the two middle activities run in parallel.
State the calendar, access restrictions, working pattern, resource assumptions and important external dependencies. A duration based on uninterrupted access should not be reused unchanged where possession windows or permits interrupt the work. The schedule basis makes those conditions available for review.
Schedule detail should serve the decision. A management view can summarise work that a delivery team plans at greater detail. Check that the views reconcile and that important logic is not lost in the summary. The RP references provide public introductions to schedule detail and documentation; the network here is an original teaching example.
In this simplified network, the civil branch finishes three working days before procurement. Civil work could therefore slip by two days without changing the project finish, assuming the same logic, calendar and unlimited availability of resources. That is a result of this model, not a promise that a real project can absorb any delay.
When answering a question, state the assumptions. Finish-to-start relationships, zero lag and a single working calendar are used here. A changed relationship, resource constraint or imposed date may change the result. Do not translate a simplified calculation into a universal programme rule.
A takes 2 working days. B takes 5 days after A. C takes 8 days after A. D takes 3 days after both B and C. All relationships are finish-to-start with zero lag; there are no resource constraints.
| Path | Duration | Result |
|---|---|---|
| A → B → D | 2 + 5 + 3 = 10 days | Shorter branch |
| A → C → D | 2 + 8 + 3 = 13 days | Governs finish |
Original network example using one working calendar. Day counts are elapsed working durations, not calendar dates.