Experimental Study on Cracking Resistance of Recycled Concrete Beams Reinforced with Hybrid Polyacrylonitrile and Recycled Fibers

In order to improve the comprehensive performance of the recycled concrete, reduce the waste of natural resources and environmental pollution, fly ash and recycled concrete aggregates were mixed into the reference concrete group RC0 to partially replace cement and natural coarse aggregates, respectively. The basic mechanical properties of five groups of recycled concrete reinforced with recycled fibers and organic fibers in different combinations were analyzed. In addition, the cracking resistance, failure process and bearing capacity of each group of recycled concrete beams were also studied. The test results and corresponding analysis showed that: the damage process of concrete beams reinforced with hybrid polyacrylonitrile fibers and recycled fibers was basically the same as that of ordinary concrete beams; the development of cracks is more effectively prevented with the increase of the proportion of waste fibers; the use of recycled waste fibers and polyacrylonitrile can significantly improve cracking resistance, deformation resistance, and load carrying capacity of recycled concrete beams.