混凝土随机参数化骨料模型及加载的数值模拟

Numerical simulation of concrete random parameterized aggregate model and load test

在细观层次上,混凝土被认为是一种由粗骨料、水泥砂浆以及二者间的黏结界面所组成的三相非均质复合材料。为此,在二维情形下,基于参数曲线的自由变形技术,将混凝土骨料及黏结界面的轮廓线用确定的、形式统一的参数方程予以表示,建立了混凝土随机参数化骨料数学模型。对骨料为卵石和碎石的混凝土,分别给出了级配、含量、配合比等可控制的随机混凝土数值试样。该数学模型描述了骨料、砂浆与黏结界面组成的二维三相复合结构形式。最后,使用MATLAB、AutoCAD和ANSYS软件建立了有限元网格模型,并进行了数值加载试验。结果表明,该方法可较好地满足混凝土动静力学性能细观数值分析的要求。

At the mesoscopic level,the concrete is considered as a kind of three-phase non-homogeneous composite materials composed of coarse aggregate,cement mortar and bonded interface between them.In the two-dimensional case,based on the technique of free-form deformation for parametric curves,the outline of every aggregate and interface is expressed by a defined and unified parametric equation,and then the concrete random parameterized aggregate model is established.When the concrete aggregate is gravel or crushed stone,the model gives a concrete random numerical structures with the controllable grade,content and rate of composite,and shows an advantage in describing two-dimensional three-phase composite materials composed of the aggregate,mortar and bonding interface.At last,the finite element mesh model and numerical load test by axial compression and tension are given by MATLAB,AutoCAD and ANSYS.The results show that the method can satisfy the requirements of numerical analysis of the static and dynamic mechanical properties of concrete.