Characterization of landslide and its earthwork solutions

Abstract

A slope has a high tendency to slide due to many factors. In any construction design, two things should be taken into account are stability and settlement. In case of landslide, a slope is not stable which mobilizing stress is higher than allowable stress. In order to reach target slope stability, earthwork solutions can be conducted. This study has the objective to characterize landslide and propose some properly alternative earthwork solutions. In order to realize the objective, field observation, literature review, laboratory test, and landslide modeling are performed. In field observation and literature review, it is obtained the geometry before and after landslide, and surrounding area condition. In this experiment, tested soil is taken from the location of landslide in Jepara, Central Java. The soil test aims to investigate index and engineering properties used as an input. In order to model earthwork in slope and to obtain its safety factor, application program Plaxis is used. From the result of tested material, the soil is dominated by granular soil with the amount of cohesive soil more than 5%. As for mechanical properties of the soil, the friction angle is and the cohesion quite high, classified as Silty Sand (SM). From modeling with Plaxis, the existing slope has safety factor (SF) 0.61 and 1.01 without reinforcement and with reinforced respectively. However with modification of slope into 5 terrace model having slope 1:1 each terrace, the SF increases 1.56.