Centrifuge study of a reduced model of a geothermal pile loaded horizontally

As part of the ANR "COOP" (Combined lOading Of energy Piles) project, the Geotechnical Centrifuge Laboratory at Gustave Eiffel University has studied the bending behaviour of a small geothermal pile, subjected to temperature cycles and horizontal head loading. It simulates a prototype pile 16 m long and 0.8 m in diameter. This study aims to predict the horizontal behaviour of reinforced concrete geothermal energy piles (GEPs) subject to lateral loads, followed by thermal loads with alternating heating and cooling cycles in saturated dense sand. The study examined three piles: a capacity pile to measure its ultimate load (Fu), a reference pile and an energy pile tested at 50% of Fu. A four-point bending test highlighted a low Young's modulus, confirming soft characteristics in the pile. Thermal loading led to significant displacement accumulation, potentially impacting both pile and soil properties. The study provided insights into failure characteristics and the impact of thermal loading on energy piles.