Analysis of Structural Equation Modeling (SEM) on the Factors of Delays in Utility Duct Work at the Mandalika Special Economic Zone (KEK) and A Comparison of Construction Method Efficiency

Abstract

This study aims to analyze the factors contributing to delays in utility duct work in the Mandalika SEZ using a structural equation modeling (SEM) approach, while also comparing the efficiency of precast and cast-in-situ construction methods. A mixed-methods approach was employed. Delay factors were analyzed using partial least squares–structural equation modeling (PLS-SEM) based on questionnaire data collected from project stakeholders. Model evaluation included construct validity and reliability testing, structural relationship analysis, and mediation effect testing. Furthermore, construction method efficiency was assessed through mathematical analysis of actual project data, incorporating field observations for quality evaluation and project documents for cost and time analysis. The SEM results indicate that the construction method has a significant direct effect on utility duct work delays. Environmental conditions significantly influence the construction method and act as an indirect factor contributing to delays. In contrast, construction management, regulation and licensing, and social and economic variables did not show significant direct effects. Efficiency analysis revealed that the cast-in-situ method provided more consistent field quality and lower costs compared to the precast method, while time performance varied depending on site conditions. Overall, the findings highlight the importance of technical and environmental factors, as well as construction method selection, in minimizing delays and improving project efficiency.