Earthquake Geotechnical Engineering

Abstract

This paper derives the best location of field sensor for landslide monitoring based on static, pseudostatic and dynamic finite element slope stability analysis. Use is made of the finite element technique as not to constrain the analysis by the assumptions required in classical approaches. Numerical techniques in general, easily handle the strain-stress relationship, the non-linear soil behaviour, and complex geometries. The present methodology is implemented in a potential landslide site at km 27 along the Cuenca-Machala highway, Ecuador. This site has a cut slope of about 40 degrees with a length of 130 m and it is 100 m wide, given an approximated landslide volume of 240,000 m 3 with an average depth of 18.5 m. The soils behaviour is represented as elastic-plastic soil material with a Mohr-Coulomb failure criterion for which the soil strength parameters were derived from in-situ and laboratory tests. The changes of static and/or dynamic stresses, geometry and soil properties will cause a variation where the highest displacements are developed. The location of the highest total, vertical and horizontal displacements are used to judge the best location for installing sensors for landslide monitoring. Different scenarios are analyzed to evaluate the effect of introducing remedial measures and different transient conditions. The results of the numerical simulation enabled definition of the most efficient and cost-effective location of the sensors to alert for potential landslides.