混凝土材料经历三向受压荷载历史后抗拉强度劣化的研究

摘要

基于连续介质损伤力学，以侧向应力和最大竖向应变二者的组合来表征混凝土所经历过的荷载历史，以抗拉强度的劣化和超声波速的降低来表征混凝土的损伤，对10cm×10cm×10cm的立方体试件进行了损伤试验，研究了单调荷载历史、循环荷载历史、不同围压条件下损伤发生、发展的一些规律.根据试验结果拟合得到损伤的演化方程，分析了影响损伤发展的主要因素，阐述了其原因.可以看出用抗拉强度的劣化以及超声波速的降低来估测混凝土的损伤是可行的.%The damage trial of concrete cube is experimentally studied.The combination of lateral stress and maximum vertical strain denotes the loading history and the reduction of tensile strength and the descent of ultrasonic velocity denotes the damage of concrete.The laws of damage initiation and development,under the conditions of monotone loading,cyclic loading and varies confinement pressure are investigated.According to the fitting of experimental data,the evolution equation of damage is obtained.The main factors affecting the damage development are examined and the causes are expounded.It is concluded that this method is feasible.