循环温度荷载下管式能量桩荷载传递机理研究

基于模型试验方法,开展加热(制冷)工作模式下,实心和管式能量桩的热响应测试研究;分析多次加热/制冷循环作用下两种能量桩的热力耦合特性,实测桩顶位移、桩身应变、以及桩侧摩阻力等变化规律,并对实际运行过程中实心和管式能量桩的承载特性进行初步讨论。研究结果表明,相同直径的管式能量桩换热效率高于实心能量桩,管式能量桩对加热循环的热响应要高于实心能量桩;多次循环后,能量桩桩顶产生塑性沉降、桩身产生微小的塑性应变,桩侧摩阻力值增加。

Thermo-mechanical Properties of Pipe Energy Pile under Cycle Temperature Load

Based on model test method, the thermal response of two kinds of precast reinforced concrete piles, the solid energy pile and hollow energy pile, was carried out under thermal cycling loads. The thermal-mechanical coupling behavior of energy piles under multiple heating cycles was analyzed. Displacement of pile head, strain and the lateral friction resistance were measured during the cycling period. The bearing capacity and shear friction of solid and hollow energy piles were studied. It shows that the hollow energy pile has higher heat transfer efficiency than the solid energy pile with same diameter. Faster responses to the thermal loads were also observed on hollow energy piles. Plastic settlement appeared after multiple heating and plastic strain was also observed on the piles. The lateral friction resistance of energy piles increased with thermal cycles, and the hollow energy pile has a faster response of lateral resistance than solid energy pile.