Geotechnical investigation of mass movements as landslides, creep and subsidence in Camp
8 and vicinity, Kennon Road, Baguio City, Benguet Province was conducted to help solve the
problems and geological hazards which are common in a mountainous terrain. These hazards, if not mitigated, have serious consequences and effects to life and property, which could run into millions of pesos.

The determination of index properties of soil samples such as moisture content, Atterberg limits, grain size, hydrometer analyses, and Triaxial Test were conducted to understand the parameters that control the mechanical behaviour of the soil. Stability analysis was studied by the Bishop Method.

The results of this investigation revealed that the rocks in the area of interest are chiefly tuff, intruded by an andesite dike and overlain by volcanic rocks (i.e., pyroclastic flow deposit and basalt flow breccia) and covered by thick residual soil. Landslides are of rotational type and occurrences of mass movements were traced to the clayey silt (ML) type of soil, characterized by its being finegrained, low plasticity, friability, medium firm consistency, high liquid limit and water content.

The two principal causes of mass movements can be attributed to the increase of the pore water pressure within the clay silt soil and the others, to the shearing stresses to which the bedrock has been subjected because of its location with respect to a splay of the active Philippine fault. This factor apparently contributed to the breakages, fracturing and instability of rocks within the study area and surrounding environment, thus causing the rapid disintegration and weathering of the rocks into relatively thick soil deposit.