I Rasoolan - Ph.D Candidate of Civil Eng, Civil Eng. Faculty, K.N.T University, Tehran
S.A Sadrnejad - Prof.of Civil Eng, Civil Eng. Faculty, K.N.T University
A.R Bagheri - Associate Prof. of Civil Eng., Civil Eng. Faculty, K.N.T University

The mechanical behavior of concrete materials is strongly influenced by its microstructure. The macroscopic properties of concrete materials such as strength and stiffness are dependent on the properties of micromechanics. The advance of composite mechanics and advanced computing technologies has made possible the micromechanical analysis of concrete materials. At first the status of micromechanical modeling with special emphasis on the advantage and disadvantage of each model is presented. The current paper focuses on the geometrical description and numerical simulation of normal-weight concrete at the mesoscale. In the first part the numerical representation of concrete at the mesoscale is introduced. The internal structure of concrete is considered at the micro level, and is treated as a three phase material comprised of aggregate particle, matrix, and the aggregate- matrix interfaces the generation of the mesoscale geometry, the finite element discretisation and the applied material laws with micro plane theory are described. The main objective of this paper is to investigate the macroscopic behavior and progressive failure of concrete materials under static loading, as influenced by the properties of its constituents at the meso level.

three phases, concrete, itz, finite element, micromechanical