ABSTRACT
The Cikareo landslide is located in southwest of Majalengka (a small town) in Java Island of Indonesia. This study led to the conclusion that the landslide developed by rotational sliding movement although the direction of sliding plane is perpendicular to the direction of stratification planes.
The analytical model was developed using a bending plate analogy and considering the deflection equation for a plate under its own weight. The tension at every point of the layer can be estimated and used to check whether the tensile strength and the resistance from the underlying layer are exceeded. This approach can be used to develop a computer program for the simulation of slope failure. The limit equilibrium factor of safety is calculated using the Janbu approach (1973) assuming the rock mass to be fractured.
Appropriate geologic investigation in the landslide area showed that the slope consists of alternate layers of coarse to fine-grained sandstone, claystone and limestone. These strata are considered to be the bottom portion of Cinambo Formation of Middle Miocene age. Sixteen rock samples were taken and tested in the laboratory. The mechanical and physical properties determined were density, porosity, cohesion, internal friction angle, compressive strength, modulus of elasticity and tensile strength. For the purpose of stability calculation, residual cohesion and residual internal friction angle were also measured.
Simulation by’using field and laboratory data proved that the Cikareo Landslide originated by rotational sliding movement.
