ABSTRACT
Let XY in Fig. 11.6(a) represent the horizontal surface of a semi-infinite mass of cohesionless soil with a unit weight y. The soil is in an initial state of elastic equilibrium. Consider a prismatic block ABCD. The depth of the block is z and the cross-sectional area of the block is unity. Since the element is symmetrical with respect to a vertical plane, the normal stress on the base AD is
(11.6) lJ'v is a principal stress. The normal stress lJ'h on the vertical planes AB or DC at depth z may be expressed as a function of vertical stress.
