Integrated analysis of geophysical approaches for slope failure characterisation

摘要

Slope failures cause significant human loss, and affect most infrastructure and transportation activities in the broad of natural hazards. The findings of the critical component in the landslide risk mitigation process were made possible by detailed investigations which rely on subsurface investigations, discrete subsurface sampling, and laboratory tests. Seismic methods and 2-D resistivity were utilised in this work to extend these approaches and study ongoing landslides activities in Malaysia. The cross-plot analysis was introduced to integrate the geophysical results based on the criteria of the model. The stiffness of the soil was revealed by velocity distributions from seismic models, with weak zones identified with values of V-p = 600 m/s and V-s = 200 m/s being designated as threshold frequency for failure to occur. The saturated zones with low resistivity values of 100 ohm m were showed in 2-D resistivity. The moderate resistivity values of 450-1400 ohm m indicated the loose sand profiles. The derivations of elastic modulus revealed the weak nature of the material in the inactive parts of the landslide (G(0) 0.1 GPa and E = 0.2 GPa) dominating at depth 5 m with Poisson's ratio varying between upsilon = 0.35-0.45. The shear strength and a rainfall data were examined to substantiate the interpretations. The cross-plot analysis allows comprehensive interpretation resulted in that low velocity and resistivity with a depth of 5 m are weak zones for materials to fail.