Thermally induced mechanical response of energy piles in axially loaded pile groups

In this study, the thermo-mechanical behavior of the energy piles in a pile group is investigated by coupled multi-physical 3D finite element analyses. The emphasis is on quantifying the changes in axial load and settlement of individual energy piles in a group subjected to combined thermo-mechanical loadings. Experimental data available in literature are used to validate the model calculation. The major influencing factors, i.e., pile spacing, pile arrangement, soil type, and end bearing condition on the energy pile response are analyzed. Based on the results obtained, it is found that the conventional thermal load causes little change in mechanical behavior of energy piles, which does not induce geotechnical failure at working load level. The observations from this study are beneficial for understanding the mechanical behavior of axially-loaded energy piles under thermal loading.