Question

Consider the following statements associated with stability of slope:
1. Stability number is inversely proportional to cohesion and directly proportional to height.
2. Swedish method of analysis is based on circular failure surfaces.
3. The Culmann method assumes that rupture will occur in a plane.
Which of these statements are correct?

• A. 2 and 3
• B. 1 and 3
• C. 1 and 2
• D. 1, 2 and 3

Answer 1

The correct option is A 2 and 3

Taylor's stability number, $S=\frac{C_m}{\gamma H}$

where, $C_m$ is unit cohesion mobilised, $\gamma$ unit weight of soil, H is height of slope
Thus, stability number is directly proportional to cohesion and inversely proportional to height. The culmann's graphical method of earth pressure determination is based on Coulomb's wedge theory. It is better than Ponclet's method and can be used for ground surface of any shape, for different types of surcharge loads, and for layered backfill with different unit weights for different layers.