混凝土在双向加载下破坏特征的试验研究

An Experimental Study on Failure Mode of Concrete under Biaxial Compressive

采用河南理工大学和加拿大McGill大学联合研究开发的双向等刚度加载系统,对C60混凝土立方体试块进行了双向和单向加载下破坏特征的试验研究。实验结果表明:在单向加载条件下,试件破坏形态为剪切破坏,尺寸效应不明显;在双向加载条件下,试件总体破坏形式为拉—剪破坏,具有延性破坏的特性,尺寸效应较明显,但是试件在双向1:1加载下要比双向2:1加载下破坏的更严重,主要是中间主应力的影响。

In order to make an experimental study on failure of C60 concrete specimens under biaxial loading and unilateral loading,we used Isotropic Biaxially Loading System（IBLS） which had been designed and established by Henan Polytechnic University of China and McGill University of Canada.The research results indicated that under the bidirectional loading environment,the Specimen failure mode was Shear failure and the size effect was not obvious;the Specimen failure mode under biaxial loading was tension-shear failure and the size effect was obvious.The damage under biaxial loading of σ1：σ2 =1：1 was more serious than that of biaxial loading of σ1：σ2=2：1;the influence was mainly intermediate principal stress.