Question

An embankment is to be constructed with a granular soil $(bulkunitweight=20kN/m^3)$
on a saturated clayey silt deposit (undrained shear strength = 25 kPa). Assuming undrained general shear failure and bearing capacity factor of 5.7, the maximum height (in m) of the embankment at the point of failure is

• A.
  7.1
• B.
  5.0
• C.
  4.5
• D.
  2.5

Answer 1

The correct option is A

7.1
Bulk unit weight,$${\gamma }_t=20kN/m^3$$
undrained shear strength,$$\tau =25kPa$$$$\Rightarrow C=25kPa$$Bearing capacity factor,$$N_c=5.7$$At the point of failure
Stress caused by = Bearing capacity embankment$${\gamma }_t\times H=C{N}_c$$$$\Rightarrow H\times 20=25\times 5.7$$Maximum height,$$H=7.125m$$