Effects of Stratigraphy on Response of Energy Piles

TL;DR

This study investigates how soil stratigraphy affects the behavior of energy piles by comparing analytical predictions with experimental data in both layered and homogeneous soils, highlighting the importance of stratigraphy in soil-structure interaction.

Contribution

It introduces and validates analytical solutions that account for stratigraphy effects on energy pile response, enhancing understanding of soil-structure interaction in layered soils.

Findings

Analytical models accurately predict pile response in homogeneous soils.

Models capture trends in axial stress and strain at layer interfaces.

Layered soil responses show more scatter and slight prediction inaccuracies.

Abstract

Energy piles are gaining increased popularity due to a growing demand for clean energy. To further advance the understanding of soil-structure interaction in energy piles, recently-derived analytical solutions have been implemented to investigate the impact of stratigraphy on the soil-structure interaction. This was accomplished by comparing the measured and predicted head displacements, axial strains and stresses in an energy pile embedded in the actual homogeneous and layered soil profiles, as well as into synthetic homogeneous soil profiles. The analytical solutions for homogeneous soil profile captured the smooth experimentally observed response versus depth very well. In the case of a layered soil profile, the corresponding analytical model was capable of capturing nuances in trends of axial stress and strain versus depth at the interface of different layers. The analytical predictions for the layered profile appear to be slightly less accurate than for the homogenous profile. The experimental data obtained from the layered profile appear to be a bit more scattered than those from the homogeneous profile. In the former case, the interplay of the individual soil layers with the pile occurs while maintaining the continuity of the pile stress and displacement at the interface of different layers. The response throughout each layer of the layered profile is quantitatively different than the corresponding homogeneous response. Nevertheless, qualitatively the response throughout each layer of the layered profile is similar to the response of the pile embedded in the corresponding homogeneous layer.