碾压混凝土试件细观损伤断裂的强度与尺寸效应分析

为了实现碾压混凝土试件强度性能的仿真计算分析 ,在细观层次上将试件看成是由硬化水泥粉煤灰砂浆、粗骨料、二者之间的粘结带及水泥砂浆中间层面形成的非均质复合材料 ,以随机骨料模型代表碾压混凝土的细观结构 ,应用非线性有限元法 ,模拟试件的细观损伤断裂 ,从而求得其宏观力学强度 ,据此可解释试件的尺寸效应 .计算结果表明 ,试件的单轴抗压强度及劈裂抗拉强度与试验结果较为吻合 ,试件的尺寸效应符合一般规律 ,该方法为碾压混凝土试件强度性能的数值模拟提供了一种新的技术途径 .

Strength and size effect analyses of mesolevel damage fracture for RCC specimen s

In order to realize a numerical simulation of strength characteristics for rolled compacted concrete(RCC) specimens, in meso-level specimens are taken as a non-uniform composite of hardening fly ash-cement mortar, coarse aggregate, bond layer between each other and middle layer of cement mortar, meso-level structures of RCC are represented with random aggregate model, by means of nonlinear finite element model the meso-level damage fracture of specimens are simulated, then the macro level strength of specimens is obtained, with this method the size effect of specimens will be explained. The results of compute showing that the uniaxial compression strength and split strength of specimens are approximately coincident with the experiment results, and the size effect of specimens is agree with the common rule. This method provides a kind of new technique of numerical simulation for the strength characteristics of RCC specimens.