Effect of Crack Growth on the Overall Mechanical Properties of Cement Composites

This paper describes how cement-based composites, reinforced with randomly distributed short fibers exhibe a nonlinear behavior called damage. This could be described in terms of microcrack initiation, growth and coalescence, which leads to the creation of macrocracks. A micromechanics-based continuum damage mechanics, MBCDM, model is proposed for the prediction of the effect of initial microcrack configuration and propagation on the macroscopic Young’s modulus and thermodynamic force associated with the chosen damage variable. Parametric studies for a number of periodic crack distributions in a two-dimensional case have been carried out in this paper. Both unreinforced (brittle) and pitch-based carbon fiber reinforced thin sheet cementitious materials have also been considered. It is shown that despite the relative simplicity of the damage measure used, the model was able to capture the main effects of cracking patterns on the overall behavior of the composite. Simulation results also reveal that, whereas the evolution of the normalized stiffness is practically the same for all configurations over the entire range of damage variation, the damage thermodynamic force is different for each case. The results predicted by the proposed approach, appear to be consistent with experimental observations regarding tensile behavior of CFRC composites.

Language

  • English

Media Info

  • Media Type: Print
  • Features: Figures; References; Tables;
  • Pagination: pp 193-206
  • Monograph Title: Thin Reinforced Cement-Based Products and Construction Systems

Subject/Index Terms

Filing Info

  • Accession Number: 01000580
  • Record Type: Publication
  • ISBN: 087031159X
  • Files: TRIS
  • Created Date: May 23 2005 11:45AM