陈智, 高华雨, 肖衡林, et al. In-situ Thermo-mechanical Response Test of Perfusion Energy Pile under Temperature Loading[J]. 2019, 39(4): 592-598. DOI: 10.13409/j.cnki.jdpme.2019.04.008.
In-situ Thermo-mechanical Response Test of Perfusion Energy Pile under Temperature Loading
Energy pile is a building energy-saving technology by utilizing shallow geothermal energy.It has the advantages of higher heat transfer efficiency and land saving than traditional ground source heat pump system.Heating tests were carried out on the 1#and 2#full-scale perfusion energy piles in the energy pile test base to obtain the temperature
strain
additional stress and lateral friction resistance of the pile.The thermal and mechanical responses of energy piles subjected to temperature loading(temperature rise of 10℃)of summer condition were analyzed.The test results show that:For multi-group U type heat exchange pipe arranged along the pile wall
the temperature distribution of pile body is uniform
the strain of pile body is large at both ends and small in the middle
and the maximum additional stress is located in the middle of pile.With the increase of temperature load
the lateral friction resistance of pile is positive at the top and negative at the bottom.The increase of the lateral friction resistance at the junction of positive and negative in the middle of pile is faster than that at both ends of pile.When the temperature rises to 7.5℃
the increase rate decreases.Under this test condition
the value of the additional stress of pile may exceed 1.66 MPa by fitting the law of the change of the additional stress of pile.The influence of temperature load on the bearing capacity of pile must be considered in design.