Paper number 1139

MICROMECHANICAL ANALYSIS OF FIBER-REINFORCED CONCRETE

S. Maria¹ , E. Sacco²

1Dipartimento di Ingegneria Civile, Universitµ a di Roma "Tor Vergata", Roma
2Dipartimento di Meccanica, Strutture, A. and T., Universitŕ di Cassino, Cassino

Summary

The present paper deals with the problem of modelling the complete macroscopic response of short fibre reinforced cementitious composites under unidirectional tensile loading. It is considered a concrete matrix with a periodic distribution of cracks and fibres. A cell model is used to represent the periodic microstructure and the overall properties of the composite are deŻned using the homogenization theory for material with periodic microstructure. The damage of the FRC is modeled considering the evolution of a process zone and a propagation of an initial crack, taking into account the bridging action of the bers. A new numerical procedure is developed to evaluate the nonlinear response of the material. In particular, the softening process is investigated studying a simple nonlinear algebraic equation, whose coe±cients are evaluated solving linear elastic problems. A numerical application is developed to determine the overall behavior of FRC, and to assess the proposed numerical procedure.

Keywords

fiber-reinforced concrete, micromechanics, fracture mechanics, numerical procedure.