Condition for local and general shear failure
Stress strain test (c- soil)
General shear failure at low strain, say < 5%, while for local shear failure, stress strain curve continues to rise at strains of 10 to 20%.
Angle of shear resistance :
For Phi> 36°, general shear failure Phi < 28°, local shear failure.
Penetration test
N> 30 General shear failure N≤ 5 Local shear failure.
Plate load test
Shape of the load settlement curve decides whether it is general shear failure or local shear failure.
Density Index
Ip> 70 General shear failure. Ip < 20 Local shear failure.
