KARAKTERISTIK TANAH PASIR TUFAAN PADA PROYEK BAYUNG LENCIR TEMPINO SEKSI 3

Abstract

The construction of the Bayung Lencir–Tempino Section 3 Toll Road, as part of the Trans-Sumatra Toll Road, faces geotechnical challenges due to the diverse types of soil, including volcanic residual soil. The unique characteristics of tuffaceous sand, such as its mineral content, degree of weathering, physical properties, and shear strength, cannot be fully explained using conventional soil mechanics concepts and general classifications. This study aims to identify the profile of volcanic residual soil characteristics and their impact on soil compressibility. Compressibility is calculated using the linear method and compared with the e-log-p method as well as monitoring results from settlement plates. The analysis results show that the finite element method and the e-log-p method yield the largest settlement predictions compared to actual field settlements, with deviations ranging from 2.9 to 20.2 cm. Among the five analyzed locations, three showed significant deviations for the finite element method, ranging from 5.5 to 20.2 cm. Meanwhile, the linear method provided smaller deviations, ranging from 4 to 19 cm, with the largest deviation of 19 cm occurring at only one location. These findings indicate that the linear method pretty close in predicting actual settlement under the soil conditions in this project. This study is expected to provide a deeper understanding of volcanic residual soil behavior and its contribution to the successful construction of the Trans-Sumatra Toll Road.