Technical Review of Slope Failure (Case Study of Tawangmangu-Cemorosewu Sta. 4+600 Section)

Abstract:

Tawangmangu-Sarangan highway is a national strategic road connecting two districts in two provinces; Karanganyar in Central Java and Magetan in East Java. The topography of the area is relatively high due to stiff hill and valley with the problematic geologic condition of weathered rock and silt sand. During rainy season, slope failures at some sections of this road were very often. The study to understand the cause of the failures is very important. Deep boring may have the best result to obtain soil parameter and stratigraphy of soil layer. However, this method was impossible due to the safety reason. The use of geophysic instrument such as geoelectric for the investigation combined with hand boring for soil sampling was a reasonable choice. Geoelecetric was utilized to predict soil layers properties and potential failure surface of the slope. This study was focused on the investigation on a slope failure location of Tawangmangu-Cemorosewu at Sta 4+600. Finite element software was utilized to understand the cause of previous failure and to model the most critical failure surface that may occurre in the future. Based on the modeling, the safety factor of the slope was 1.18 and 0.930 before and during construction. The condition of the slope after failure is still very critical due to the very low safety factor of 1.03 causing the potential of failure. It also recommended that geometrical method such as terrasering might be one of the solutions producing the safety fractor of 1.5.

• Periodical: Applied Mechanics and Materials (Volume 845)
• Pages: 76-82
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.845.76
• Online since: July 2016
• Authors: Alik Mustakim*, Yusep Muslih Purwana, Ary Setyawan, Mamok Suprapto
• Keywords: Geoelectric, Slope Failure, Tawangmangu-Cemorosewu

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