Verification of Scale Effect of Shallow Foundation in Determination of Bearing Capacity of Sandy Soil

Abstract

The strength parameters for sandy soil are not depending mainly on level of stresses but they are a linear function of width (B) and embedment depth (u) of footing in Terzaghi's solution of bearing capacity. On the other hand, it was found by as called the non-classical solution conducted by Parkins and Madson (1997) that this relation is nonlinear and the bearing capacity for sandy soil is mainly relating to width and depth of foundation, which is known as scale effect. In this work a field model test was carried out on compacted sandy soil bed for different types of footings with different sizes and geometry for clarification of the two aforementioned approaches. It was found that two approaches are consistent and indicating the scale effect well for bearing capacity of sandy soil. On the other hand, from the field model tests results, it is found that the two determinations give overestimated bearing capacity values, especially for rectangular footing with length to width ratio more than 5 (L/B > 5) specially by Parkins and Madson's approach rather than the Terzaghi's equation.