Experimental Research on Crack Resistance of Steel–Polyvinyl Alcohol Hybrid Fiber-Reinforced Concrete

This paper investigates the effects of steel fiber and PVA fiber hybrid blending on the compressive strength ($f_{\mathrm{c}\mathrm{c}}$), splitting tensile strength ($f_{\mathrm{t}\mathrm{s}}$), compression energy ($W_{1.0}$), and shrinkage properties of concrete. It also establishes a multi-factor crack resistance index evaluation model based on the Analytic Hierarchy Process (AHP) to comprehensively evaluate the crack resistance of concrete. The results show that the steel–PVA hybrid fiber (S-PVA HF) further enhances $f_{\mathrm{c}\mathrm{c}}$, $f_{\mathrm{t}\mathrm{s}}$, the compression energy, and the shrinkage suppression properties of the concrete. The crack resistance of the steel–PVA hybrid fiber concrete (S-PVA HFRC) is the best when the proportion of steel fiber is 1.0% and that of the PVA fiber is 0.2%, and it increases up to 143% compared to the baseline concrete. The established concrete crack resistance evaluation model has a certain reliability.