AACE International PSP - Planning & Scheduling Professional (PSP) Exam

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 usually 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​.

ï‚· 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​.

Scheduling Professional Study Guide and Documents References:

Total float is the amount of time an activity can be delayed without delaying the project's overall completion date.

Option B (buoyancy) and Option D (end of that activity) are irrelevant.

Option C refers to free float, not total float.

This definition is fundamental in critical path analysis​​.

ï‚· Position Analysis:

Activity C (Develop Draft Plans and Specifications) has a duration of 5 months and is preceded by Activity A.

The diagram positions Activity C incorrectly since it starts simultaneously with Activity B, but Activity C should start after the completion of Activity A.

ï‚· Cross-Verification:

Based on the dependencies, Activity C’s incorrect positioning violates the logical sequencing rule.

ï‚· Verification with PSP Guidelines:

Correct logic representation is critical for network diagrams (Ref: PSP Study Guide, Chapter 2A: Logical Sequencing).

ï‚· Activity 11001 Characteristics:

Activity 11001 (Spillway - Concrete) is logically defined as the final activity in the project.

Final activities in a project typically do not have successor activities since they signify project completion.

ï‚· Exclusion of Other Options:

Option A: Circular logic does not apply since the scheduling logic is linear and follows standard precedence diagramming methods.

Option B: Activity 11001 is not penultimate but the final activity.

Option C: The scheduler's error is highly unlikely in a controlled environment following PSP principles.

ï‚· Verification with PSP Guidelines:

The PSP Study Guide explains that final activities represent the culmination of a project's logical sequence and typically lack successors (Ref: PSP Study Guide, Chapter 2A: Logical Sequencing).

ï‚· Purpose of Multiple Calendars:

Multiple calendars account for varied work/non-work periods among resources, regions, or activities, accurately representing project execution.

ï‚· Evaluation of Other Options:

B, C, D: These may be secondary benefits but are not the primary reason.

ï‚· Verification with PSP Guidelines:

The PSP Study Guide emphasizes the importance of calendars for realistic scheduling (Ref: PSP Study Guide, Chapter 2A: Calendars and Constraints).

ï‚· Role of Project Schedules:

Schedules primarily control time, cost, and resource allocations.

Quality management is related to design specifications and execution standards, not directly managed by schedules.

ï‚· PSP Study Guide References:

The guide clarifies the limitations of scheduling tools in managing quality aspects​.

ï‚· Conclusion: The correct answer is A, as project schedules do not directly control quality.

To calculate the duration:

Total hours required: 240 hours.

Daily work hours per crew: 5 workers × 8 hours/day = 40 hours/day.

Duration = Total hours ÷ Daily work hours = 240 ÷ 40 = 6 days.

This calculation aligns with standard resource planning principles​.