Potensi Pemanfaatan Rel Bekas Sebagai Pengganti Dinding Penahan Tanah (DPT) Untuk Mendukung Mitigasi Bencana Kelongsoran Tanah

Abstract

Used railway rails are one of the non-hazardous waste materials generated from the operational activities of PT Bukit Asam (PTBA). These materials tend to accumulate in storage areas because they are difficult to reuse through conventional recycling processes. Therefore, an alternative utilization method is required to reduce waste accumulation while providing additional functional value. One potential application is the use of used rails as retaining walls. This concept is based on the mechanical properties of steel rails, which possess high structural capacity, good stiffness, and a cross-sectional shape similar to steel piles used in sheet pile retaining wall systems. PTBA has implemented this method by installing used rails vertically at the toe of slopes in mining areas susceptible to instability. The installation is intended to increase the lateral resistance of the soil, thereby restraining soil mass movement and improving slope stability. To evaluate its effectiveness, a numerical analysis was conducted using a finite element method-based program. The analysis compared slope conditions before and after the installation of used rails under two soil types, namely sandy soil and clayey soil. The results indicate that, prior to rail installation, the slopes did not satisfy the required safety criteria, with factors of safety of 0.918 for sandy soil and 1.147 for clayey soil. Following the installation of the used rails, the factors of safety increased significantly to 1.565 and 1.545, respectively. These findings demonstrate that used rails can effectively function as retaining walls to enhance slope stability and offer a promising innovative solution for waste material management in the mining industry.