DESIGN OF RETAINING WALLS FOR LANDSLIDE MITIGATION ON THE BULONTIO—TOLINGGULA ROAD SEGMENT, NORTH GORONTALO REGENCY, GORONTALO PROVINCE

Abstract

The Bulontio—Tolinggula Road section, located in North Gorontalo Regency, was experiencing landslide issues caused by low soil bearing capacity. An analysis of the existing slope conditions indicates a factor of safety that signifies instability. To address this issue, a technical solution is required through the design of a retaining wall. Calculations are carried out using Rankine’s theory for normal earth pressure conditions and the Mononobe-Okabe theory for seismic conditions. The analysis results show that a gravity wall requires larger dimensions compared to a cantilever wall to achieve the same level of stability. Furthermore, the use of pile strengthening significantly increases the factor of safety, especially under seismic conditions. Segmental pile strengthening also proves to be effective and economical, enhancing stability without compromising structural safety. After implementing the retaining wall and pile strengthening, safety factors (SF) were achieved for sliding, overturning, bearing capacity, and global stability. These analysis and design results provide a solution to overcome landslide problems in disaster-prone areas and support the development of safe and sustainable transportation infrastructure.

Keywords: Landslide, Retaining Wall, Pile, Stability, Safety Factor