ABSTRACT:

The paper deals with geotechnical study and optimum slope design of lumpy chromite ore mine. The sensitivity analysis was done to determine the factor of safety in undrained condition. The rock discontinuities were mapped as per the suggested methods of International Society of Rock Mechanics. Geotechnical mapping was undertaken to determine the critical orientation of structural discontinuities. Kinematic analysis was done to determine the types of failure in the rock slopes of the mine. The geo-mechanical tests of different lithological units were conducted. The failure analysis was done by GALENA software, which shows that the 160 m high southern and 65 m high northern slopes of the open pit mine may have an overall slope angle of 44 and 53 degree respectively.

INTRODUCTION

The paper deals with geotechnical study and optimum slope design of lumpy chromite mine of M/s Jindal Stainless Ltd.. The mine is situated in Orissa state of India. The strike length of the quarry will be 320 m. The ore body is about 10 m wide dipping at an angle of 85 deg. towards south. The Cr2O3 is +35%. The mine is being developed to produce 40,000 tonne of ore with 6.5 lakhs m3 OB. The life of the mine is 10 years. The average rainfall in the area is about 900 mm/ annum. About 90% of the precipitation in the valley escapes as surface run off.

The rock discontinuities were mapped along the exposures at the upper horizons of lumpy ore quarry as per the suggested methods of International Society of Rock Mechanics (ISRM 1978). Geotechnical mapping was undertaken to determine the critical orientation of structural discontinuities. After identifying kinematically possible failure modes, detailed slope stability analysis is carried out. The sensitivity analysis was done to determine the factor of safety in undrained condition.

This content is only available via PDF.
You can access this article if you purchase or spend a download.