. A granite rock formation consists of three sets of discontinuities where the average joint spacing is 320 mm. The RQD of the rock cores obtained from the boreholes is 68%. The joint surfaces are rough, stepped and unweathered, with no separation. The average uniaxial compressive strength of the intact rock cores is 200 MPa. The surface of excavation is found to be damp. Determine the RMR value, disregarding the rating adjustment for discontinuity orientation. What values would you use for cohesion and friction angle in analysis of the rock mass?

. A granite rock formation consists of three sets of discontinuities where the average joint spacing is 320 mm. The RQD of the rock cores obtained from the boreholes is 68%. The joint surfaces are rough, stepped and unweathered, with no separation. The average uniaxial compressive strength of the intact rock cores is 200 MPa. The surface of excavation is found to be damp. Determine the RMR value, disregarding the rating adjustment for discontinuity orientation. What values would you use for cohesion and friction angle in analysis of the rock mass?

Principles of Foundation Engineering (MindTap Course List)

9th Edition

ISBN:9781337705028

Author:Braja M. Das, Nagaratnam Sivakugan

Publisher:Braja M. Das, Nagaratnam Sivakugan

Chapter7: Ultimate Bearing Capacity Of Shallow Foundations: Special Cases

Section: Chapter Questions

Problem 7.16P

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