(1. College of Civil Engineering，Chongqing University，Chongqing 400045，China；2. Academy of Dazu Rock Carvings，Chongqing 402360，China；3. Chongqing Bureau of Geology and Minerals Exploration，Chongqing 401121，China)
Abstract：Currently，the research on the thermo-mechanical response of energy piles primarily focuses on vertical loads，while studies considering the influence of horizontal loads are relatively limited. To investigate the thermo-mechanical response characteristics of horizontally loaded energy piles，a model test was conducted to analyze the variations in pile top displacement，pile bending moment，pore pressure，and soil pressure in front of the pile under different temperature gradients in saturated clay. The research results showed that both heating and cooling of the pile induced additional pile top displacement，with cooling causing a larger additional displacement，reaching 0.22%D (D is the diameter of the pile)，while heating induced an additional displacement of 0.13%D. The ultimate bearing capacity of the pile increased after heating/cooling compared to the ultimate bearing capacity pile，with a greater increase observed after heating，approximately 32.7%，compared to an increase of approximately 26.1% after cooling. This was due to the significant increase in the strength of the soil caused by the thermal consolidation effect during heating. Heating and cooling did not have a significant impact on the location of the maximum bending moment，as the maximum bending moment consistently occurred at 37.5%L (L is the burial depth of the pile) before and after heating/cooling. The maximum bending moment increased after heating/cooling. During cooling，the maximum bending moment initially increased and then stabilized gradually. During heating，the maximum bending moment decreased first and then gradually increased，exceeding the pre-heating moment. Throughout heating period，the pile top displacement continued to increase，suggesting that the pile may undergo rigid rotation in the initial stage of heating. Heating and cooling have different effects on the soil pressure in front of the pile. Overall，the upper part of the soil pressure generally increased and the lower part decreased. Heating and cooling caused variations in pore pressure in the soil，resulting in positive or negative excess pore pressure.
