Value Engineering For Deep Excavation Retaining Systems With A Balanced Budget Approach

Abstract

This study evaluates the change in a deep-excavation retaining system from Strutting & King Post to Diaphragm Wall at the Harapan Kita–Tokushukai Heart Hospital Project using a Value Engineering approach with a balanced-budget criterion. A quantitative comparative-evaluative case-study design was applied. Primary data were obtained from 12 project professionals purposively selected from an operational population of 19 personnel, while secondary data included cost estimates, bills of quantities, design and geotechnical documents, schedules, Value Engineering documents, and change-order records. The analysis combined FAST, Cost/Worth Ratio, instrument validity and reliability, descriptive statistics, Shapiro-Wilk testing, Wilcoxon Signed-Rank testing, weighted performance, cost reconciliation, balanced-budget analysis, and Value Index calculation. The Diaphragm Wall alternative achieved higher technical performance and constructability, shortened the affected works by approximately eight weeks, and reduced cost from IDR 25.445 billion to IDR 25.031 billion, equivalent to 1.63% savings. Weighted performance increased from 3.0532 to 3.9826, while the Value Index rose from 0.611 to 0.810. The alternative therefore provided higher value for this case, subject to technical, contractual, and safety verification before implementation.