Analisis Daya Dukung Struktur Bawah Pada Integrasi Jembatan Terpisah Ditinjau dari Alinyemen Jalan Nasional Semarang-Surakarta Kecamatan Bergas

Abstract

The Semarang–Surakarta National Road in Bergas District is a 4/2 divided national arterial road that currently uses two separate bridge structures. This study aims to evaluate the road geometric alignment and the safety of the substructure for a single-bridge configuration based on PDGJ 2021, Minister of Public Works and Housing Regulation No. 19 of 2023, and SNI 1725:2016. The analysis was conducted using manual calculations and AllPile 6.5 software. The results show that the existing horizontal alignment does not meet the minimum radius requirement of 230 m specified in PDGJ 2021, while the vertical curves do not meet the minimum safety values of 30 for sag curves and 26 for crest curves. The substructure analysis indicates that the soil bearing capacity, sliding stability, and overturning stability meet the safety requirements, with a safety factor (SF) ≥ 1.5. The AllPile 6.5 analysis also shows that the well foundation is capable of resisting the applied axial, lateral, and moment loads, with a foundation settlement of 1.11 cm, which is less than the allowable limit of 2 cm. Therefore, the substructure is considered safe to support a single bridge structure.