chapter  11
3 Pages

7b

RANKINE'S ACTIVE EARTH PRESSURE WITH COHESIVE BACKFILL

The point P2 at which the circle cuts the ground line represents the lateral earth pressure. The length OP2 measures 47.5 kN/m2.

1 Hence the active thrust per unit length, Pa =- x 47.5 x 8 =190 kN/m2

11.6 RANKINE'S ACTIVE EARTH PRESSURE WITH COHESIVE BACKFILL In Fig. 11.13(a) is shown a prismatic element in a semi-infinite mass with a horizontal surface. The vertical pressure on the base AD of the element at depth z is

The horizontal pressure on the element when the mass is in a state of plastic equilibrium may be determined by making use of Mohr's stress diagram [Fig. 11.13(b)].