The energy pile with embedded steel tube is a new type of ground source heat pump (GSHP) technique in the form of pipe-coupled pile. However

there are few studies focused on thermal response of this new pipe form. Experimental test and numerical simulation were conducted to study the heat transfer from tube to steel tube

to concrete

and to soil of energy piles with single U-shaped embedded steel tube. Temperature variations of surrounding soil and pile shaft under temperature loading of heating-cooling cyclic were measured. The thermal response of the ordinary single U-shaped heat exchanger energy pile with tied tube was also tested for comparative analysis. Finally

the applicability of energy pile with embedded steel tube was analyzed. The results show that the thermal response of energy pile with embedded steel tube is slightly lower than that of energy pile with tied tube. The final temperature of surrounding soil and pile shaft of two types of energy pile varies 23% and 16% in summer

and 14% and 18% in winter.