高温后型钢再生混凝土梁变形性能及刚度计算

通过16根高温后型钢再生混凝土梁静力加载试验,观察其受力破坏过程及形态,获取受力破坏全过程的荷载-挠度曲线,深入分析再生粗骨料取代率和高温温度对型钢再生混凝土梁变形性能的影响,并探讨其刚度的计算方法。研究结果表明:高温后型钢再生混凝土梁具有良好的变形性能;温度对其变形性能有一定的影响,温度越高,初始刚度和峰值荷载越小;取代率对其变形性能影响不大;根据叠加法理论和JGJ138—2001《型钢混凝土组合结构技术规程》的方法,提出的修正刚度计算式可近似用于高温后型钢再生混凝土梁的短期刚度计算。

DEFORMATION PERFORMANCE AND CALCULATION OF FLEXURAL RIGIDITY OF STEEL REINFORCED RECYCLED AGGREGATE CONCRETE BEAMS AFTER HIGH TEMPERATURE

Based on the static load tests of 16 steel reinforced recycled aggregate concrete( SRRAC) beams after high temperature,the damage process and failure mode of specimens were observed,and the load-deflection curves were obtained. The effects of replacement ratio of recycled aggregate concrete and high temperature on SRRAC beams were investigated,and the method to calculate flexural rigidity was analyzed. The test results indicated that the SRRAC beams after high temperature had a good deformation performance. It was shown that temperature had an influence on deformation performance of SRRAC beams,i. e. increasing the temperature caused a decrease of initial flexural rigidity as well as peak load. However,replacement ratio had little influence on deformation performance. Based on superposition method and Technical Specification for Steel Reinforced Concrete Composite Structure( JGJ 138—2001),the post-correction formula was proposed to calculate the flexural rigidity of SRRAC beams after high temperature.