Apparatus development for contact mechanics of energy pile-soil interface

¹ School of Earth Sciences and Engineering, Nanjing University, 210023 Nanjing, China
² Key Laboratory of Earth Fissures Geological Disaster, Ministry of Land and Resources (Geological Survey of Jiangsu Province), Nanjing 210018, China

^* Corresponding author: zhangdan@nju.edu.cn

Abstract

An Energy Pile-Soil Interface Characteristic Apparatus (EPSICA) was developed to investigate the contact mechanics of the pile-soil interface. In the center of the apparatus, there is an energy pile model, around which different soil can be filled to simulate pile in different subsoil. The soil can be saturated. By applying loads on the top of the soil, the different depths were simulated. The temperature of energy piles was controlled by the cycling fluid with a water bath. The Pt100 sensors were installed in the pile and soil to measure the temperature changes. The miniature earth pressure cells were installed on the pile surface to measure the normal stress of the pile-soil interface. The FBG quasi-distributed optical fiber technology was used to measure the hoop strain to evaluate the circumferential deformation of the pile model. Taking the sand foundation as an example, the mechanical behavior of pile-soil contact behavior during the heating and cooling cycle was studied based on the temperature of pile and soil, normal stress of pile-soil interface and hoop strain of pile. The developed apparatus provides a new method for the study of thermos-mechanical behavior of energy pile.