Question

When the high value of σϴ in the vicinity of the walls of a shaft exceeds the compressive strength it results in __________

(a) Plastic flow of soil

(b) Non uniform stress distribution

(c) Increase fluid pressure

(d) All of the mentioned

I had been asked this question in exam.

My question is based upon Stress Distribution in the Vicinity of Shafts topic in section Shafts, Tunnels and Conduits of Geotechnical Engineering II

Answer 1

Right option is (a) Plastic flow of soil

For explanation I would say: The high value of σϴ in the vicinity of walls of a shaft may exceed the compressive strength of the soil, resulting in a plastic flow of the soil which continues until a state of plastic equilibrium.