压剪作用下 PVA 纤维再生混凝土力学性能试验研究

In order to study the influence of polyvinyl alcohol (PVA) fiber on the mechanical properties of recycled aggregate concrete under compression and shear, 144 cubes were designed and fabricated using replacement rate of recycled coarse aggregate, compressive stress ratio and volume content of PVA fiber as the changing parameters. The specimen is subjected to compression shear test. The failure mode of the specimen was observed, the load⁃displacement curve and the vertical deformation⁃shear displacement curve were obtained, and the influence of different changing parameters on the shear strength and peak displacement was analyzed. The results show that: the shear strength of recycled concrete with 0.1% PVA fiber increased by 10%; with the increase of compressive stress ratio, the shear strength of the specimen increased by 2.03 times on average. Compared with ordinary concrete, the shear strength of recycled concrete decreases by 13% on average%. When the replacement rate of recycled coarse aggregate is 100%, the optimum content of PVA fiber is 0.1%; the calculation formula of the shear strength of PVA fiber recycled aggregate concrete under compression and shear is proposed when the content of fiber is 0.1%.