Rock failure mechanism

Rock failure mechanism

1. Plane failure

It is possible under the following conditions.

a. The dip direction of planar feature (joint, bedding, foliation) is at the same direction (+/-)20 degree as that of the hill slope.

b. The dip amount of hill slope is usually higher than that of the planar features.

c. The dip amount of the failure plane must be greater than angle of friction.

2. Wedge failure

It is possible under the following conditions.

a. Two planes intersects obliquely across the slope face and their line of intersection dips at the same direction (+/-)20 degree at the dip direction at hill slope.

b. The dip amount of the line of intersection is less than that of hill slope.

c. The dip amount of the line of intersection is greater than angle of friction.

3. Toppling failure

It occurs under the following condition.

a. The plannar features dip opposite to the hill slope

b. The fall slope is steep enough than planar failures i.e. hill slope is at least 55 degree.