Horizontal impedance of square foundation in layered soil

This paper presents an extensive investigation into the influence of key mechanical and geometrical parameters on horizontal impedance of square foundations resting on or embedded in a two-layer soil deposit. The parameters investigated are the ratio of shear-wave velocities, the thickness of the top layer, the depth of embedment and the degree of contact between the footing-sidewall with backfill-soil. The results are presented in the form of simple and versatile dimensionless graphs, which should prove to be useful in understanding the steady-state harmonic response of square foundations in layered soils due to horizontal excitation. The investigation was conducted using a rigorous boundary element algorithm incorporating isoparametric boundary elements. Higher order quadratic elements were used since they can model the wavy nature of the dynamic problem investigated more accurately.

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