Stratified Soils and Westergaard's Analysis

Westergaard's analysis is a theoretical approach used in geotechnical engineering to determine the distribution of stresses and pressures exerted by loads applied to the surface of the soil mass. This method offers an alternative perspective compared to Boussinesq's theory.

The applicability of Westergaard's analysis is rooted in its assumptions regarding the behavior of the subgrade material. While basic Westergaard theory assumes an infinitely elastic medium, its formulation is particularly adapted for situations involving surface loads, such as those found in pavement design or on rigid foundations.

A key aspect making Westergaard's analysis suitable for stratified soils is its consideration of the medium's layering. Unlike theories that assume a completely homogeneous material, Westergaard's approach implicitly or explicitly handles scenarios where the soil mass consists of distinct layers, each potentially having different elastic properties (like modulus of elasticity and Poisson's ratio). This characteristic aligns well with the nature of stratified soils, where layers of different materials (e.g., sand, clay, gravel) are present.

Westergaard's method is often considered when:

• The load is applied on a rigid surface.
• Considering the influence of the medium's rigidity and Poisson's ratio.
• Analyzing stress distribution in layered systems (stratified soils).

Therefore, Westergaard's analysis is particularly relevant for understanding stress concentrations and distributions within layered soil profiles, commonly referred to as stratified soils.