Numerical Analyses of Mechanical Behaviors of Concrete

摘要

Taking concrete as a type of three-phase composite material comprising mortar matrix,aggregate and the interface between mortar matrix and aggregate.Using the random aggregate models reflects the grades of concrete. At the mesoscopic level,meshing the mesofinite element,the element types,i.e.matrix elements,aggregate elements and bond elements,are distinguished and assigned to corresponding material properties. The material parameters are given to consider the interface characteristic,as well as the strain vate effects of elastic modulus and strength.Based on the aforementioned assumption a series of the numerical simulations are conducted to investigate the influences of the property of interface zones,specimen size affect,load rate,static preload,concrete quality,aggregate grades and aggregate geometric shapes on the macro-mechanical behaviors. The computational results demonstrate that the meso-mechanics model can well reflect the predominating characteristics of the meso-structure heterogeneity of concrete,and meso-mechanics method can be used to efficiently analyze the mechanical behaviors.