The Effect of Short Metallic and Polymeric Fiber on the Fracture Behavior of Cement Mortar

摘要

A study has been made concerning the influence of short randomly oriented steel and polypropylene fibers on the fracture of cement mortar. With regard to the steel fibers, different fiber volume fractions were considered and the results obtained indicated an increase in the J-integral values, at the onset of mortar cracking and at maximum load, as the fiber content was increased. This improvement in the toughness level was attributed to the fiber bridging effect which enhances the capacity of the reinforced mortar to deform and hence to sustain higher load than that sustained by plain mortar. Compressive strength and modulus of elasticity also were improved due to the presence of steel fibers whose elastic modulus is much higher than that of the mortar. The use of short polypropylene fibers reinforcing elements was also associated with an appreciable improvement in the mortar's toughness as well as in its flexural strength. However, consistent with their low elastic modulus, the polypropylene fibers resulted in reducing the mortar's compressive strength.