基于数字图像的混凝土破坏过程的数值模拟  

DIGITAL IMAGE-BASED NUMERICAL SIMULATION ON FAILURE PROCESS OF CONCRETE

作　　者：于庆磊[1] 唐春安[2] 朱万成[1] 唐世斌[2] 

机构地区：[1]东北大学资源与土木工程学院工程力学所,沈阳110004 [2]大连理工大学土木与水利学院,大连辽宁116024

出　　处：《工程力学》2008年第9期72-78,共7页Engineering Mechanics

基　　金：国家自然科学基金重点项目(40638040);国家自然科学基金资助项目(10672028)

摘　　要：把混凝土看作是由水泥砂浆为基相,粗细骨料为分散相的复合材料。在细观尺度上,应用数字图像处理技术表征混凝土材料中由骨料的形状、大小和分布对混凝土材料造成的非均匀性,在组成相材料内部细微观尺度上,采用统计方法来描述材料的非均匀性,建立了细-微观尺度耦合分析的混凝土损伤数值模型,模拟了混凝土单轴载荷作用下的破坏过程。数值模拟结果能反映出骨料分布和组成相材料的非均匀性对混凝土力学行为的影响,较好的模拟了混凝土试样从裂纹萌生扩展到宏观裂纹形成的整个破坏过程。Concrete is considered to be one of two-phase composite materials composed of cement matrix and aggregates. At meso-scale level, the digital image processing method is used as a measurement tool to construct a digital representation for the distribution and the shape of aggregates in concrete; and at micro-scale level, statistical method is used to describe the inhomogeneity of component materials. A multi-scale coupled numerical model that can simulated damage evolution of concrete under loading is proposed by taking into account the material inhomogeneity at micro-scale and meso-scale level. The failure process of concrete is simulated by this model under uniaxial stress. The computing results show that this model can take into account the influence of the distribution of aggregates and respective heterogeneity of component materials on mechanical performance of concrete and is able to capture the complete failure process of concrete materials that includes the initiation, propagation and coalescence of microcracks as well as cracking pattem associated with different loading stages.

关 键 词：数字图像 混凝土 破坏过程 非均匀性 细观尺度 微观尺度 

分 类 号：TU528.01[建筑科学—建筑技术科学]