Question

The inclination of failure plane behind a vertical wall filled with cohesionless soil $(\varphi ={36}^0)$ in passive earth case from vertical is

• A. ${27}^0$
• B. ${36}^0$
• C. ${45}^0$
• D. ${63}^0$

Answer 1

The correct option is D ${63}^0$



Failure plane makes an angle $45+\frac{\varphi }{2}$ from major principal axis. In passive case, major prinicpal axis is vertical.

$=45+\frac{36}{2}={63}^0$
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