Effects of PVA fiber on mechanical properties of composite modified recycled concrete
To clarify the effects of the volume fraction and length of polyvinyl alcohol(PVA)fibers,as well as the impact of composite modified recycled aggregate of sodium silicate and silane on the mechanical properties of recycled concrete,mechanical tests were conducted on six groups with different fiber volume fractions and lengths,along with two control groups.The test results were analyzed using variance analysis.The results indi-cate that both the composite modification of recycled aggregate with silane and sodium silicate and the addition of PVA fibers can effectively enhance the mechanical properties of recycled concrete.The mechanical proper-ties of modified recycled concrete showed a significant improvement compared to unmodified concrete.When 0.1%volume fraction and 9 mm length of PVA fibers were incorporated,the mechanical properties of recycled concrete reached the optimal level.Observing the appearance of cracks after splitting tensile failure,it was found that the 12 mm PVA fibers exhibited better effects in inhibiting crack propagation and expansion.Vari-ance analysis using SPSS software revealed that the fiber volume fraction is the primary factor affecting the me-chanical properties of recycled concrete.