简单介绍了以应力、应变及能量表达的混凝土破坏准则,指出应变破坏准则不仅能反映材料破坏的形变本质,还具有应用方便等诸多优点.为了方便描述混凝土在应变空间的破坏面,引入了Haigh-Westergaard坐标系,并介绍了应变的H-W不变量、应变张量的不变量和主应变的平均值、标准差之间的换算关系.在分析国内外混凝土强度和形变试验资料的基础上,提出了在Haigh-Westergaard坐标系中由应变的H-W不变量表示的应变空间破坏准则的一般式和简化式.拟合得到了一种C50混凝土的应变空间破坏准则的各个参数值,并对一般式和简化式进行了比较,指出一般式适用于各种形变状态,简化式在一定条件下能满足工程应用的要求.%The failure criterions of concrete expressing by stress, strain or energy are introduced simply. It is pointed out that strain failure criterion can reflect the deformation essence of failure of material and has many advantages such as using easily. The Haigh-Westergaard coordinates are used to express the failure surface of concrete in strain space, and the conversion relationship between H-W invariant of strain, invariant of strain tensor and the average and variance of principal strain is introduced. By the analysis of the strength and deformation test data of concrete at home and abroad, a general formula of failure criterion in strain space and its simplified one are put forward, which is expressed by H-W invariant of strain in the Haigh-Westergaard coordinates. The parameter values of failure criterion in strain space about a C50 concrete are obtained by fitting, and a comparison between general and simplified formula is made. It is indicated that the general formula is suitable for every deformation state and the simplified one meets the application demands of engineering to some extent.
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