Performance and Modeling of Secant Pile Reinforced by Soil Nailing for Urban Excavation in Jakarta

Abstract

This article presents an excavation case which is located in Jakarta, Indonesia. It adopted secant piles reinforced by soil nailing as the retaining wall system. The excavation area is ± 3673 m2 and the average excavation depth is 12.0 m. The predominant soil was silty clay with a soft to medium consistency. Besides the standard soil investigations, Pressuremeter test also performed to measure the in-situ soil modulus accurately. In addition, the wall deformations were well monitored with Inclinometer. Later, a 2D finite element analysis was conducted to investigate the performance of the retaining wall system. The soil was modeled with the hardening soil model. The results showed that the measured soil modulus obtained from Pressuremeter could be used a basis for determining soil modulus input parameters, rather than using empirical correlations. The shape of wall deflection was a cantilever shape and the maximum wall deflection was 45 mm. Also, the computed wall deflection was agreed with the measured data. Moreover, the parametric study on the soil nailing length and inclination also conducted to investigate the deformation characteristic of this retaining wall system.