高温喷水冷却后钢筋再生混凝土梁受力#br# 性能试验及承载力计算

为研究高温喷水冷却后钢筋再生混凝土(卵石类)梁的力学性能，以温度、取代率、冷却方式和剪跨比为变化参数，对28个试件进行高温喷水冷却后的静载试验。观察试件的表观变化、受力破坏形态，获取其荷载 挠度曲线及力学性能指标。基于试验实测数据，深入分析各变化参数对试件力学性能的影响，并探讨其承载力的计算方法。研究结果表明：高温喷水冷却后，试件发生破损，受力破坏形态表现为弯曲破坏和斜压破坏，钢筋再生混凝土梁比普通钢筋混凝土梁具有更好的力学性能；随着温度的升高，承载力先增大后减小，而延性和耗能能力逐渐变差；随着取代率的提高，承载力、延性和耗能能力具有小幅增大的趋势，增幅在10%以内；冷却方式对承载力影响显著，而对延性和耗能能力无明显影响；剪跨比越小，承载力越大，但延性和耗能能力越差；最后，建议采用修正后的欧洲规范计算高温喷水冷却后钢筋再生混凝土梁的承载力。

Mechanical behavior test and bearing capacity calculation of reinforced recycled#br# concrete beam subjected to high temperature and subsequent water cooling

 In order to investigate the mechanical behavior of reinforced recycled concrete (pebble) beam subjected to high temperature and subsequent water cooling，the static load tests of 28 specimens under high temperature and water cooling were carried out with temperature，replacement ratio，cooling method and shear span ratio as analysis parametersThe apparent change and failure mode of the specimens were observed，and the load deflection curves and mechanical performance indexes were obtainedBased on the test data，the effects of various parameters on the mechanical behavior of specimens were analyzed，and the calculation method of the bearing capacity was discussedThe results show that the specimens are damaged under high temperature and subsequent water cooling，and the failure modes are bending failure and baroclinic failureThe mechanical behavior of the reinforced recycled concrete beam is better than that of normal reinforced concrete beam after high temperature and water coolingWith the increase of temperature，the bearing capacity increases first and then decreases，while the ductility and energy dissipation capacity gradually deteriorateWith the increase of replacement ratio，the bearing capacity，ductility and energy dissipation capacity have a slight increase less than 10%The cooling method expose a significant effect on the bearing capacity，but not on the ductility and energy dissipation capacityThe smaller the shear span ratio，the larger the bearing capacity，but the worse the ductility and energy dissipation capacityFinally，the revised European code is recommended to calculate the bearing capacity of the reinforced concrete beam after high temperature and water cooling.