. An existing 75° inclined rock slope with a joint dipping at the same direction at 40° and the
joint cuts the slope from its toe. The slope is 15 m in height, and at the top of slope there is a
flat plateau with a vertical tension crack located 3 m behind the crest of the slope. The tension
crack stops when it reaches the joint surface. The existing groundwater level is at 2 m below
the surface of the top plateau. The strength parameters of the rock joint: c = 35 kPa, φ = 35°.
The unit weight of rock is 26 kN/m3
and the unit weight of water is 9.81 kN/m3
.
a) Determine the factor of safety of the slope.
b) What reinforcing bolt force should be applied on the slope face to upgrade the safety
factor to 1.4? Assume that the inclination of bolt angle measures 15° from horizontal
