Mechanical properties and damage constitutive of recycled aggregate concrete with polyvinyl alcohol fiber under compression and shear

Abstract

This paper researched the mechanical properties and damage constitutive of polyvinyl alcohol (PVA) fiber recycled aggregate concrete (RAC) under compression and shear. A total of 102 cube specimens were performed considering the effects of PVA fiber volume content, replacement ratios of recycled coarse aggregate, and normal stress. The shear strength, peak shear displacement and shear force-displacement relation of RAC were analyzed. The test results show that the shear strength increases with increasing normal stress and decreases with increasing replacement ratios of recycled coarse aggregate. The maximal shear strength generally appears at a PVA fiber content between 0.05 % and 0.1 % when identical to the normal stress and replacement ratios of recycled coarse aggregate. The peak shear displacement increases with increasing normal stress and PVA fiber volume content. The optimal PVA fiber content was 0.1 % considering the shear strength and shear displacement. It is suggested that a damage constitutive model be used to explain the shear force-displacement relationship of PVA fiber RAC in a compression-shear composite stress condition. The test findings and calculation results showed good consistency, proving that the damage constitutive model suggested in this research is applicable to PVA fiber RAC.