Low Wall Slope Stability Design on Swamp Material Using Bishop and Janbu Simplified Limit Equilibrium Method

Abstract:

Coal mine slope stability is an important aspect of mining activities. The research site is located at Pit PQRT in Berau Regency, East Kalimantan. The research area is a freshwater peat swamp area located on a delta plain with tidal influence. The swamp material is located on the low wall side of the mine. Slope stability in the study area, which is composed of soft swamp material needs special attention because it is a major problem in the design of mining slope geometry. However, the availability of mine slope infrastructure in the form of active roads and sediment ponds also needs attention. Slope stability analyses were conducted using the Bishop Simplified and Janbu Simplified limit equilibrium methods. The slope geometry design at elevation-16 to-13 is 3 meters bench height, 20 degrees slope angle, and 15 m bench width. The elevations are-10 to-1, the bench height is 3 meters, bench width is 20 m. At elevation +2 the bench width is 35 m, and at elevation +5 the bench width is 40 m. The overall slope analysis results using the Bishop Simplified method the safety factor is 1.37 while in the Janbu Simplified method, the safety factor is 1.31. In the calculation of the safety factor considering active roads and sediment ponds the safety factor is 1.57.

• Periodical: Engineering Headway (Volume 20)
• Pages: 23-33
• DOI: https://doi.org/10.4028/p-nCPk4E
• Online since: March 2025
• Authors: Nahar Said Said, Purwanto Purwanto*, Muhammad Ramli
• Keywords: Bishop Simplified, Janbu Simplified, Slope Geometry Design, Swamp Material

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