Awarded as the best online publication by CIDC

Soil Engineering

What is the Lateral Pressure In Soils?

We know that The Rankine theory of lateral earth pressures is the most widely used theory to find the lateral pressure which is acting on retaining walls. But this theory has some assumptions which we need to know before hand.

Assumptions in the Rankine Theory of Lateral Earth Pressures
1) The pressure on the back of a vertical wall is the same as the pressure that would exist on a vertical plane in an infinite soil mass.
2) Their is no Friction between the wall and the soil.

What is the Lateral Pressure of Cohesive Soils?

P=1/2YH2KA-2cH(KA)1/2
where
Y=unit weight of soil, lb/ft3 or kg/m3
P=total thrust of soil, lb / linear ft (kg/m) of wall
H= total height of wall, ft (m)
KA= coefficient of active pressure
c= cohesion, lb/ft2or kPa

Physical Properties Of Soils

The soil properties and parameters can be broadly classified as
1)Physical
2)Engineering
3)Index

Physical soil properties include specific gravity, density, particle size and distribution and water content.
The water content represented by w of a soil sample is defined as the weight of free water in the sample expressed as a percentage of its dry weight.

The degree of saturation S is defined as the ratio of the volume of free water to its total volume of voids Vv

n=Vv/V
where n is the Porosity defined as the ratio of void volume to the total volume V of soil.
(more…)