Select all true statements. 1-Direct shear tests are useful to establish the Mohr-Coulomb envelope for intact rock. 2-In the stress-strain curve, yield occurs when the deformation becomes plastic. 3-When discontinuities are present in a rock mass, failure can occur along intact rock or along discontinuities. 4- In the stress-strain curve, strain-softening is observed between the yield point and the peak strength. 5-A lower Geological Strength Index (GSI) implies smaller Mb and s rock constants and a poor-quality rock mass.

Select all true statements. 1-Direct shear tests are useful to establish the Mohr-Coulomb envelope for intact rock. 2-In the stress-strain curve, yield occurs when the deformation becomes plastic. 3-When discontinuities are present in a rock mass, failure can occur along intact rock or along discontinuities. 4- In the stress-strain curve, strain-softening is observed between the yield point and the peak strength. 5-A lower Geological Strength Index (GSI) implies smaller Mb and s rock constants and a poor-quality 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

Chapter8: Vertical Stress Increase In Soil

Section: Chapter Questions

Problem 8.13P

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