【摘要】 本文对按应变能密度理论和最大拉应变理论所推导出的两个三维复合型断裂临界曲面作了简要介绍.并叙述了以35组混凝土试样进行Ⅰ-Ⅱ、Ⅰ-Ⅲ和Ⅰ-Ⅱ-Ⅲ型各种复合型断裂破坏试验为依据所得出的混凝土材料的两个试验临界断裂曲面.结果表明,按最大拉应变理论所得到的理论临界曲面和试验临界曲面相当接近.由本试验所得到的临界断裂曲面,及其拟台的经验判据式为判别含各种复台状态裂纹的工程构件中的裂纹是否会失稳扩展,提供了一个准则.更多还原

【Abstract】 Introduced in this paper are two fracture critical surfaces of three dimensional mixed mode obtained from the theory of strain energy density factor and the theory of maximum tensile strain. Other two fracture critical surfaces of Ⅰ-Ⅱ, Ⅰ-Ⅲ and Ⅰ-Ⅱ-Ⅲ modes from 35 groups of specimens of concrete are described. The results show that the theoretical and experimental critical surfaces of the maximum tensile strain are very close. The criterion given by the experimental critical surface of the maximum tensile strain can be used in the analysis of the instable cracking of structural members with cracks of all types of mixed mode.更多还原