Comparison of slope remediation method on slope stability of man-made slope

Abstract

This research discuss about the comparison of slope remediation method on slope stability of man-made slope. This research includes identifying the soil characteristics on the affected slope, evaluation slope stability based on factor of safety (FOS) and cost consumption of remediation method. Soil nailing and cantilever retaining wall had been proposed and tested using slope simulation. In cantilever retaining wall, two backfill materials also had been proposed, using sand and glass. Retaining wall with size 2 m x 0.5 m at base and 3.5 m of height had been designed in slope simulation and fill by concrete. Meanwhile, soil nailing had been designed by different length, which is 4.5 m, 5.0 m, 5.5 m, 6.0 m, 6.5 m and 7.0 m, diameter of steel is 0.025 m. Among these methods, the result obtained from evaluation of FOS before and after remedial process had been analysed. When sand use as a backfill material, the value of FOS for cantilever retaining wall shows 1.214 without existence of pore water pressure (PWP), meanwhile 1.215 for existence of PWP. Meanwhile uses of glass shows 1.532 and 1.533 without the presence of PWP and with the presence PWP respectively. Soil nailing shows that 1.402 and 1.319 when without the presence of PWP and presence of PWP respectively. Cost consumption for remedial process is RM30, 006.50 for retaining wall and RM41, 423.80 for soil nailing. From that, it can be concluded that sand is a good backfill material, meanwhile soil nailing depends on strength and length of steel. Glass can be proposed in backfill material in future. Strength and length of soil nailing steel needed for improvise to increase the soil nailing capability to achieve FOS value 1.5 and above.