Schedule Performance Evaluation Using S-Curve Analysis: A Case Study of a Settlement Infrastructure Project

Abstract

Schedule performance is a critical determinant of success in construction projects, particularly in settlement infrastructure, where limited resources and complex implementation processes often lead to imbalanced progress distribution. This study aims to evaluate the distribution of planned project progress using an S-curve–based approach and to identify deviations from an ideal linear schedule. A quantitative descriptive method with a case study approach was applied to a settlement infrastructure improvement project in Samarinda, Indonesia. The analysis utilized project planning data, including work breakdown structures, weekly progress, and cumulative progress, which were examined through S-curve modeling, deviation analysis against linear progress, and weekly progress intensity based on slope evaluation. The results indicate that the project schedule distribution is highly non-linear. In the early phase, cumulative progress reached only 5.59% despite one-third of the project duration having elapsed, while more than 63% of total progress was concentrated in the middle phase (Weeks 5–9), with peak weekly progress approaching 20%. This concentration reflects a high level of schedule sensitivity, where disruptions during the middle phase could significantly impact overall project completion. The findings demonstrate that S-curve analysis is effective in identifying workload concentration, critical phases, and potential delay risks at the planning stage. It is concluded that project time management strategies should prioritize control during high-intensity phases to improve schedule performance in infrastructure construction projects.