水饱和大骨料混凝土单轴拉动态内时损伤模型

摘要

The free water in the pores of the concrete affects its dynamic mechanical properties ,however ,related re-search of this effect is scarce .In view of the reduction of concrete tensile strength caused by pore water ,the reasons were explained from the mesoscopic level based on the Stefan effect and fracture mechanics .And then with the consideration of strain rate and coarse aggregate in saturated state ,a dynamic tensile constitutive model of saturated coarse aggregate con -crete was established based on the endochronic theory and damage mechanics .The comparison of the simulation and test results indicates that the constitutive model can reflect the mechanical properties of saturated coarse aggregate concrete under dynamic tensile stress .%孔隙水给混凝土的动态力学性能带来一些影响，但是目前这方面的理论研究甚微。针对孔隙中的自由水降低了混凝土的抗拉强度，利用 Stefan 效应及断裂力学概念从细观层次上解释了自由水降低混凝土抗拉强度的原因，在水饱和状态下考虑应变率及大骨料因素，应用内时理论和损伤力学建立了饱和大骨料混凝土的动态受拉本构模型。理论计算与试验结果对比表明：本构模型可较好的反映饱和大骨料混凝土动态受拉力学性能。