SHEAR PROPERTIES EXPERIMENT OF STEEL REINFORCED RECYCLED AGGREGATE CONCRETE BEAMS AFTER ELEVATED TEMPERATURES

To study the shear properties of steel reinforced recycled aggregate concrete beams subjected to elevated temperatures，17 specimens were designed for static load test under different elevated temperatures，and the replacement rates of recycled coarse aggregate，temperatures and concrete strength grades were considered． The physical and mechanical properties of steel reinforced recycled aggregate concrete beams after different temperatures were tested． The damage processes and patterns were observed． The load-midspan deflection curves and ultimate bearing capacities were obtained． The influence regularities of varying parameters on the initial stiffness，peak stresses，the ductility coefficients and energy dissipation of steel reinforced recycled aggregate concrete beams subjected to elevated temperatures were analyzed． The results showed that as the increase of temperatures，the masses of steel reinforced recycled aggregate concrete beams lost; initial stiffness and peak stresses decreased; the ductility coefficient and energy dissipation first decreased and then increased． As the increase of replacement ratios， mechanical properties changed a little． As the increase of concrete strength，the initial stiffness and peak stresses increased; the ductility coefficient was smaller; energy dissipation changed rarely．