Effect of polypropylene fiber content on compressive and flexural performance of recycled concrete

Abstract

Recycled concrete was a kind of green, environmental protection and energy-saving building material, and its mechanical properties can be improved by adding polypropylene fiber. Taking the polypropylene fiber content as a parameter, experiment of cube compressive strength and bending strength on polypropylene fiber recycled aggregate concrete (PFRAC) and natural aggregate concrete were done, among which the PFRAC has 50% replacement rate of recycled aggregate. Through the comparison of strength and fracture mode of specimens, the influence of polypropylene fiber content on the pressure resistance and fracture resistance of recycled concrete were studied, and the recycled concrete’s appropriate amount of polypropylene fiber which strength can reach to natural aggregate concrete were obtained. The results were as follows: the compressive strength and bending strength of recycled concrete with polypropylene fiber were obviously intensified and the strength continuously intensifies along with the adding of fiber content. The compressive strength and bending strength of PFARC exceed that of natural aggregate concrete when fiber content was up to 1.0kg/m3. The recycled concrete with polypropylene fiber can still maintain the property of crack without breaking after damage, and the britttle fracture morphology wouldn’t occur in it.