TWO-SCALE NUMERICAL HOMOGENIZATION OF THE CONSTITUTIVE PARAMETERS OF REACTIVE POWDER CONCRETE

The paper is concerned with the modeling of reactive powder concrete (RPC) by using the method of numerical homogenization. More specifically, a two-scale modeling approach and the finite element method are used. The behavior of a model of RPC on the macro scale is described on the basis of the phenomena occurring in the microstructure of the material. The applied approach makes it possible to take into account the microstructure of material as concerns the different mechanical properties of its constituents. The method does not require any knowledge of the constitutive equations at the macro level, which are determined implicitly by solving a boundary value problem for a representative volume element (RVE) of RPC on the micro level. In order to determine the constitutive equations on the macro scale it is necessary to know the layout of microstructure, the constitutive equations at the micro level, and their parameters. In this contribution the response of each of the concrete constituents (cement matrix, sand, crushed quartz) is assumed to be elastic. The microstructure of RPC concrete is randomly generated. A computer program for the two-scale homogenization of 2D disks has been developed and numerical results for micro and micro macro test problems are presented. Further studies of the considered problem, including also laboratory experiments, are under way.