基于损伤的PHC桩单轴受拉动态本构模型研究

摘要

Based on the strain rate enhancement factor, damage weakening factor and pre-stressed enhancement factor, this paper has analyzed their impact on the strength of pre-stressed concrete and established a uniaxial tensile dynamic constitutive model which is used to describe the impact properties of PHC piles under impact load.The model simulation results were compared with the experimental results, which shows that the results indicated by this model is good agreement with the deformation trend and agreement with the experimental results in numerical accuracy.The results of this paper can provide the basis for controlling the vibration parameters in the process of vibrating pile.%通过引入应变率强化因子、损伤弱化因子和预应力强化因子,并分析它们对预应力混凝土强度的影响,建立了一个单轴受拉动态水构模型用于描述PHC桩在冲击载荷作用下的冲击特性.对比了试验结果与该模型的数值模拟结果,结果表明:模型预示结果在变形趋势上符合很好,在数值精度上与试验结果符合良好.本成果可为振动沉桩过程中控制振动锤参数提供依据,能有效防止因拉应力过大而导致PHC桩被拉断的事故.