Fracture Toughness of Fiber Reinforced Concrete.
Progress rept. Jun 82-Jun 83,
NORTHWESTERN UNIV EVANSTON IL DEPT OF CIVIL ENGINEERING
Pagination or Media Count:
For fiber reinforced cement based composites, the principal beneficial effects of fibers metallic, mineral or organic accure after the matrix has cracked. For loads beyond which the matrix has initially cracked, the further crack extension and opening is resisted by bridging of fibers across the cracks. The resistance provided by the fibers will depend prinicipally on the debonding and the pull-out resistance of fibers. A theoretical model based on the concepts of nonlinear fracture mechanics to predict the resistance provided by the fibers against the fracture of matrix is presented in this report. The theoretically predicted response is compared favorably with the experimental data on notched beams and double cantilever beam specimens of steel fiber reinforced concrete. The proposed theoretical model provides a method to calculate fracture resistance for a crack extension in a specimen of any geometry. One of the key parameters required for the model is the relationship between the uniaxial post-cracking stress and the corresponding displacement. This relationship will depend on the bond-slip function of fibers. A method to estimate this relationship is presented.
- Ceramics, Refractories and Glass
- Laminates and Composite Materials
- Construction Equipment, Materials and Supplies