钢-混凝土组合箱梁抗震性能试验

Experiment of seismic performance for steel-concrete composite box-beam

进行了4组不同剪力连接度与腹板高厚比的组合箱梁低周反复荷载试验,对组合箱梁的失效模式、滞回性能、骨架曲线、耗能能力、延性、刚度退化规律等抗震性能进行了深入研究,重点分析了腹板高厚比和剪力连接度对组合箱梁抗震性能的影响。研究结果表明:由于腹板高厚比和剪力连接度的不同,组合箱梁存在局部屈曲破坏、弯剪破坏、压弯破坏和剪切破坏4种失效模式;荷载-挠度滞回曲线和骨架曲线可分为弹性、弹塑性与破坏3个阶段;不同剪力连接度与腹板高厚比情况下的荷载-挠度滞回环丰满而稳定,没有明显的捏缩现象,体现良好的抗震性能;剪力连接度越大,组合箱梁骨架曲线越饱满,耗能能力越强,但延性变化不明显;腹板高厚比越大,组合箱梁延性越好,耗能能力越强;剪力连接度与腹板高厚比对组合箱梁刚度退化前期有较大影响,后期影响变小。

Four steel-concrete composite box-beams （SCCBBs）with different shear connection degrees and height-width ratios of web were experimentally studied under low-cyclic reversed loading.The seismic performances,such as failure mode,hysteretic behavior,skeleton curve, energy-dissipating capacity,ductility,and rigidity degeneration rule,were deeply studied.The influences of shear connection degree and height-width ratio of web on the seismic performance were mainly analyzed.Study result shows that according to different shear connection degrees and height-width ratios of web,there are four types of failure modes,which are local buckling failure,bending-cutting failure,compressing-bending failure,and shear failure.Load-deflection hysteretic curve and skeleton curve can be divided into three stages that are elasticity, elastoplasticity,and failure.Load-deflection hysteretic loops,with different shear connection degrees and height-width ratios of web,are plump and do not have obvious rheostriction,which shows that SCCBB has good seismic performances.Skeleton curve becomes plumper and energy-dissipating capacity becomes higher when shear connection degree increases,but the change of ductility is not obvious.Ductility becomes better and energy-dissipating capacity bocomes higher when the height-width ratio of web increases.The influences of shear connection degree and height-width ratio of web on rigidity degeneration are greater at earlier stage and less at later stage.3 tabs,12 figs,22 refs.