Analysis of Bearing Capacity and Foundation Settlement of Luan Linggi Bridge, Aceh Province, Indonesia

Abstract

A bridge is a structure made to cross a ravine or obstacle such as a river, railroad, or highway. The bridge consists of an upper structure and a lower structure. The upper structure of a building must be able to be supported by its own lower structure, namely the foundation. There are two types of foundations, namely shallow foundations and deep foundations. The planning of a foundation is said to be correct if the load that is forwarded by the foundation to the ground does not exceed the strength of the soil. Luan Linggi Bridge is one of the bridges that uses deep foundations in the form of pile foundations. This bridge is located in Luan Linggi Village, East Simeulu District, Simeulue Regency, Aceh Province, Indonesia. Due to the 2004 Tsunami disaster, the bridge pillars were broken and the abutments shifted, so the bridge could no longer be used. So, the bridge was redesigned in 2015 and rebuilt in 2021. This study aims to determine the value of the bearing capacity of a single foundation, the value of the bearing capacity of the group foundation, and the foundation settlement. This research uses N-SPT data, soil physical and mechanical properties, and detailed engineering design (DED). The method used to calculate the bearing capacity of the foundation is the Luciano Decourt method, while the single foundation settlement uses the Vesic method. The results obtained from this research are the bearing capacity and settlement value of the pile foundation with a diameter of 40 cm and a depth of 22 m. The ultimate bearing capacity value of the single foundation obtained is 375,228 tons, the permit bearing capacity value of the single foundation is 125,076 tons, the bearing capacity value of the group foundation obtained is 5887,727 tons. The elastic settlement value of the foundation using the Vesic method is 2,88 cm, and the settlement value of the group foundation is 8,8 cm.