Authors : Abdul Samad Abdul Rahman, Mohd Jamaludin Md Noor, Ismacahyadi Bagus Mohd Jais and Mohd Raizamzamani Md Zain
Abstract: Causes of slope failures to occur normally by the water infiltration. That is the common factor that triggered slope to fail in tropical countries. When water infiltrates into the soil, the magnitude of suction diminishes and in thus, the shear strength also reduces. At zero suction the shear strength envelope correspond to the shear strength at saturation which is commonly thought as the lowest shear strength. Analysis proved that many slopes are still stable even though being infiltrated to the failure depth and this has puzzled the engineers of how the slope has failed. This study will substantiate that the lowest shear strength is not the shear strength at saturation. The shear strength envelope is further lowered when the soil constituent is soaked within certain period of time. This has been the common triggering factor in slope failure caused by rainfall infiltration that never being incorporated in slope stability analysis and design. A laboratory test was conducted for granitic residual soil in consolidated drained triaxial test for unsoaked and soaked for 14 days and will be presented with respect to shear strength effect and stability analysis applying linear and non-linear failure envelope have been conducted and compared.
Abdul Samad Abdul Rahman, Mohd Jamaludin Md Noor, Ismacahyadi Bagus Mohd Jais and Mohd Raizamzamani Md Zain, 2019. Degredation of Curvi-linear Shear Strength Envelope at Failure Due to Soaking Effect. Journal of Engineering and Applied Sciences, 14: 9209-9213.