Studies of Geomechanical Properties Using Subsurface Borehole Logging

This dissertation aims to address the importance of geomechanical studies not just in the oil and gas industry but also in construction engineering, mining and hydrological industry. There are numerous methods to conduct this study but this project places emphasis on utilizing subsurface borehole data with laboratory data to further validate the findings. Universiti Teknologi PETRONAS is a vast area with impressive state of the art architecture, hence proper geomechanical study of the area is vital since there have never been a study like this conducted before. Two cross sections and a land survey map are constructed to study the local geology of the area. Triaxial compression test, compaction / CBR test and particle size distribution are among the tests conducted to study the compressive strength, elastic constants, stress parameters, grain size and sorting and load bearing capacity of the collected samples. There is an abundance of clay and silt up to 13 meters below ground level and limestone from about 15 meters onwards which is believed to be of Kinta origin. The soil disturbance is caused by mining activities in the past. The soil samples obtained is comprised of mainly poorly sorted gravel on the shallower depth and moderately sorted clay and silt in a slightly deeper depth. The sandy silt sample (CBR value from 10 - 20) located south- east to the Chancellor Hall has a maximum dry density of 1.733 mg/m3 with optimum moisture content of 18% where its strength is at its highest. The Mohr circle plotted shows that the soil has a cohesion value of 2kN/m2, angle of internal friction 26.1º where the maximum shear stress that it can handle is 45kN/m2 and maximum normal stress is 87kN/m2 before failure