细观结构对混凝土动态力学特性的影响研究

Effect of Mesostructure on the Dynamic Mechanical Properties of Concrete

混凝土作为非均质复合材料,其力学特性受材料的微细观结构形态影响比较明显,物理试验很难将各因素孤立出来单独考虑其对混凝土力学特性的影响,本文从数值试验入手,把混凝土看作是由骨料、砂浆以及界面组成的三相材料,研究动压和动拉荷载作用下细观结构中诸如骨料位置、单元尺寸、材料强度以及骨料粒径对混凝土动态力学特性的影响,发现混凝土的细观结构对其动态力学特性有影响,不同因素对混凝土动态力学特性影响权重不同,相同因素在不同荷载作用下的影响结果也不同。

Concrete is a nonhomogeneous composite material.Thus,its mechanical properties are affected by its mesostructure,and the isolation of the influences of various factors on the mechanical properties of concrete is difficult.In this study,concrete is considered as a three-phase material that consists of aggregates,mortar,and interface.Numerical experiments are conducted to analyze the influence of microstructural parameters(e.g.,aggregate position,element size,material strength,and aggregate size)on the properties of concrete under dynamic compressive load and dynamic tensile load.The mesostructure of concrete affects the dynamic mechanical properties of concrete.However,different factors have different weights,and the same factor may exert different effects under different loads.