Study On Mechanical Properties And Durability Of Glass Fiber Recycled Concrete

With the rapid development of cities,along with the surge and excessive accumulation of construction waste,waste of land resources and serious environmental pollution,it is the general trend of the current national conditions for the state to adhere to the road of sustainable development and realize recycling economy.Starting from the recycled construction waste,the recycled coarse aggregate is processed and pretreated by soaking in 10%PVA solution to make up for the high water absorption rate caused by its own cracks and covering the old cement mortar,and improve the basic performance of recycled aggregate to prepare recycled aggregate concrete.The influence of adding glass fiber on the mechanical properties and durability of recycled concrete was studied by controlling the length and content.The test results showed that adding glass fiber improved the overall compressive strength of recycled concrete,and the best length was 6mm with 0.1%content,and the compressive strength of 6mm>12mm>3mm.0.2%dosage of 6mm is the best,with 6mm compressive strength>3mm compressive strength>12mm compressive strength,and the compressive strength of 0.1%dosage is higher than that of 0.2%dosage,which is higher than that of the control group.Glass fiber can inhibit the long-term splitting tensile strength of recycled concrete.The splitting tensile strength of specimens after 28 days is lower than that of RA,and only the 0.2%content can improve the early strength.In the durability study,the chloride-wet-dry cycle has no obvious loss on the quality of the specimen,but the loss of compressive strength shows after 100d days of cycle,and the loss of splitting tensile strength shows after 75 days of cycle.Chloride ion soaks into the eroded specimen,and the strength gradually loses with the number of cycles.The chloride ion permeability resistance test showed that the electric flux of RA reached5000C,which decreased by 6.9%～19.5%after adding glass fiber,and F₁₂RA_0.2was the best group.Glass fiber improves the defects of recycled concrete,such as high porosity and easy to be eroded by chloride ions,and has a remarkable effect on improving the durability of recycled concrete.Figure[59]Table[16]Reference[70]...