 Time-Scaled Logic Diagrams :

Represent activities with respect to a time scale (e.g., a calendar).

Show logic al relationships and durations in a visually aligned manner, aiding in analysis and reporting.

 Common Misconceptions :

They are not the same as pure logic diagrams (B).

While often created using computer software, manual versions are also possible, so (A ) is incorrect.

They are not specifically for calculating activity durations (C).

 PSP Study Guide References :

The guide identifies time-scaled logic diagrams as a tool for better visualization of schedules, where activities align with calendar dates​.

 Conclusion : The correct answer is D , as time-scaled logic diagrams are drawn to align activities with a calendar.

 Definition of a Summary Activity (Hammock):

A summary activity, also referred to as a hammock activity, spans mult iple detailed tasks and is governed by the earliest start (ES) of the first task and the latest finish (LF) of the last task.

 Activities 6001 through 6003 Overview:

6001: Starts after 5001 (Drill and Grout Dam Site).

6003: Ends before 8001 (Rock Fill to elevation 50).

 Identifying Predecessor and Successor:

Predecessor: Activity 5001 (Drill and Grout Dam Site).

Successor: Activity 8001 (Rock Fill to elevation 50).

 Cross-Verification:

Logical and temporal dependencies confirm that Activity 5001 must precede the hammock, and Activity 8001 must succeed it (Ref: PSP Study Guide, Chapter 2A: Logical Sequencing and Activity Relationships

Understanding As-Built Critical Path Analysis:

Determining the as-built critical path of a project involves identifying the sequence of activities that actually dictated the completion of the project. This is especially important in projects that are underway, as schedules often deviate from the original baseline due to progress updates and unplanned changes​​.

Explanation of Each Option:

A. Use the progressed portion of the critical path of all the updates previous to the current update: This is correct. To determine the most likely as-built critical path, analyzing the progressed portion of the critical path from all previous updates provides the most accurate representation of the project’s actual execution. By reviewing the progression over time, you can piece together the actual sequence of critical activities​​.

B. Use the progressed portion of the critical path of the baseline schedule: This is incorrect. The baseline schedule reflects the original plan, which may no longer be accurate due to progress deviations, delays, or changes in logic. Using the baseline alone does not account for the dynamic nature of the project​.

C. Interview the project personnel for their perceptions and opinions because the schedule is usua lly inadequate: This is incorrect. While project personnel may provide insights, relying solely on subjective opinions introduces biases and inconsistencies. A properly maintained and updated schedule is far more reliable for determining the critical path​.

D. Use the forward-looking critical path of the most current updates: This is incorrect. The forward-looking critical path only reflects what is expected to happen from the current point onward. It does not provide an accurate representation of the as-built critical path up to the current point​.

 Study Guide References:

The PSP Study Guide emphasizes the importance of analyzing progress updates to trace the actual sequence of critical activities. Section 2.3.2 (Tracking Schedule Progress) discusses the role of historical updates in understanding project performance​.

The guide also highlights that a proper as-built analysis requires a review of all updates to identify shifts in the critical path over time​.

 The Late Finish (LF) of Activity 7001, when compared with dependencies in the precedence diagram, does not align with logical flow, indicating an error in its calculation.

 Validat ing LF involves backward pass calculations, which must respect lags and durations.

 References : PSP Study Guide, Section 2.3.4 – Schedule Change Management , and 2.4.3 – Schedule Analysis , focus on identifying and correcting logic or calculation errors in schedules.