Numerical investigation of the effects of thermal expansion coefficient of pile and soil on the mechanical response of energy pile

Document Type : Research Article


1 Civil Engineering Faculty, Sharif university of technology, Tehran, Iran

2 Civil Engineering Faculty, Sharif University of Technology, Tehran, Iran


Considering the environmental pollution resulting from the consumption of fossil fuels, replacing clean energy with fossil fuels has become one of the most critical issues in the world. In order to exchange the heat between superstructures and the ground, the use of energy piles can be considered as an approach to take advantage of clean energy. In order to maintain the safety and serviceability of structures built on energy piles, it is necessary to properly study the effects of heat exchange between energy piles and the ground on the mechanical response of energy piles and the influence of various parameters on the interaction between piles and the soil. In this paper, a 3D finite difference model was initially created using FLAC software for the thermo - mechanical analysis of energy piles, and it was validated by comparing the results of the present model with those of field tests and numerical models performed by other researchers. Using the present numerical model, the effects of changing the thermal expansion coefficient of the energy pile and clayey soil on axial stress, shaft friction, and axial displacement along the energy pile under cyclic thermal loading have been investigated. The results indicate that changing the thermal expansion coefficient of pile materials causes significant changes in the behavior of energy piles under heating and cooling conditions; however, changing the thermal expansion coefficient of the soil has little effect on the mechanical behavior of the energy pile during heating thermal loading.


Main Subjects

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