Geotechnical study and optimum slope design of Tirap Colliery, Assam, India

The paper deals with geotechnical study for optimum slope design of Tirap Colliery, Assam, India, with special reference to steep southern highwall slopes. Geotechnical mapping was done on the exposed benches of the quarry. The different geo-mechanical properties of lithological units were determined. Initially kinematic analysis was done to determine the types of failure in the slopes with respect to the measured discontinuities in the field. The failure analysis was done by GALENA software. An assessment of the engineering and structural geology, strength properties and the related geotechnical controls indicated that the 216 m high ultimate southern slopes of the colliery may have an overall slope angle of 31 0 .