Analisis Kendala Pemodelan BIM 3D pada Pondasi Concrete Spun Pile Rumah Pompa Studi Kesesuaian Visual terhadap Metode Konstruksi Lapangan

Abstract

Concrete Spun Pile (CSP) foundations are widely used as key structural elements in the Terboyo Pump House construction of the Semarang–Demak Toll Road Section 1C project. CSP piles with lengths of 60 m and 62 m are installed as full-length elements according to the actual field method and later trimmed at the pile head to achieve the final design elevation. The discrepancy between the as-installed condition and the as-designed condition creates challenges in 3D BIM modeling using Autodesk Revit, as the software does not directly provide a visual representation of construction-stage changes within a single modeled element. This study aims to analyze the modeling constraints of CSP foundations in BIM 3D and evaluate the visual consistency of the model with the actual construction method. A quantitative descriptive approach was applied through a case study of the Pump House structure. The data used include foundation design drawings, pile length specifications, design elevations, and the resulting 3D models. Modeling was conducted under two scenarios: (1) modeling based on the actual installation length, and (2) modeling based on the final elevation after trimming. The results show that modeling CSP piles using full installation length accurately represents the field construction method but does not reflect the final design condition. Conversely, modeling directly according to the post-trimming elevation produces an accurate design visualization but does not depict the actual construction stages. Additional modeling strategies such as element separation, the use of parts, or phasing configurations are required to resolve these inconsistencies. This study provides a recommended 3D BIM modeling workflow for CSP foundation work to improve visualization accuracy and coordination in infrastructure projects