Study on the Influence of Heat Exchange of Static Drill Rooted Energy Pile on the Consolidation of Coastal Soft Soil Site

Abstract

The use of static drill-rooted energy piles in deep soft soil foundations causes thermal exchange between the piles and the surrounding soil, resulting in excess pore pressure and consolidation settlement in the soft soil layer around the piles, which affects the long-term deformation of the site. To investigate the impact of the operation of this novel energy pile on the consolidation of the soil around the pile, a simulation analysis was conducted using the ABAQUS software to assess the soil temperature, pore pressure, and consolidation settlement around the static drill rooted energy pile group under a 120-day heating and cooling cycle. The research findings indicated that the temperature change decreased as the distance between the soil and the pile increased, resulting in less thermal consolidation settlement and pore pressure variations. Heating conditions (ΔT = 18.7°C) resulted in a 17°C increase in the soil temperature below the center of the pile group, with temperature changes becoming negligible beyond 8D. The maximum pore pressure variations in the soil occurred at 2D and 6D distances from the pile, with values of 1.24 and 1.12 kPa, respectively. Under heating conditions, the surface settlement at a 2D distance from the pile group was 6.19 mm, which increased to about 10 mm under heating–cooling cycles. These research findings provide a foundation for analyzing the environmental impact of novel energy piles in coastal areas.