S-Curve Monitoring - Worked Examples

Example 1: Computing Cumulative Accomplishment

An irrigation system rehabilitation project has a total contract amount of 12,000,000 PHP. By Month 3, the cumulative actual billing for completed earthworks and canal lining is 4,500,000 PHP. Calculate the Cumulative Progress Percentage.

Example 2: Analyzing Delayed Progress against the S-Curve Envelope

At Month 4 of a dam construction project, the Early-Start curve requires 55% progress, and the Late-Start curve allows a minimum of 42% progress. The field inspector reports the actual accomplishment at 38%. Determine the project status and Progress Variance.

Example 3: Formulating a Recovery Strategy

Following the delayed progress in Example 2 (-17% variance), the project manager needs to prepare a recovery plan. The delay was primarily caused by the late delivery of cement and rebars. What are the recommended actions?

Example 4: Calculating EVM Schedule Performance Index (SPI)

At the end of Month 6, an irrigation canal project has a planned completion of 60% according to the Early-Start baseline. The validated actual progress is 48%. Compute the Schedule Performance Index (SPI) and assess the project speed.

Example 5: Forecasting Completion based on SPI

Using the SPI of 0.80 from Example 4, if the project has an originally approved duration of 12 months, forecast the estimated duration at completion assuming the current work rate continues.

Example 6: Validating Actual Progress Data in an Irrigation Project

A contractor claims 50% accomplishment for a canal lining activity. However, the site engineer observes that while 50% of the reinforcing steel bars have been delivered, only 30% of the actual concrete pouring has been completed. How should this be evaluated for the S-Curve?

Example 7: Diagnosing Causes of Schedule Slippage

At Month 8, actual progress has dropped 12% below the Early-Start curve and 5% below the Late-Start curve. The project involves excavation, embankment, and structure works. What steps should the engineer take to diagnose the slippage?

Example 8: Catch-up Planning via Resource Addition

Following the diagnosis in Example 7, the project must recover 5% of schedule slippage. The primary constraint is embankment compaction which is currently limited by the availability of only one vibratory roller. Formulate a catch-up plan.

Example 9: Corrective Reporting and Action Escalation

A project engineer observes a negative schedule variance of -15% on a dam spillway project. The delay is traced to late approval of variation orders by the central office, meaning the contractor cannot proceed with structural excavation. How should this be reported?