钢框架组合深梁结构抗震性能试验研究

Experimental study on seismic behavior of steel frame filled with composite deep beams

钢框架、钢框架内填剪力墙反映了框架结构刚度值从小到大的两个端点值,刚度增幅是突变性质的。本文提出的钢框架内填钢-混凝土组合深梁可以满足两个端点刚度值之间的要求,实现宽范围的刚度渐变调幅。通过低周反复加载的试验方法,综合考虑深梁高宽比等因素,对两榀钢框架组合深梁结构和一榀纯钢框架进行了对比试验,试验得出了结构在低周反复荷载作用下的滞回曲线、应力分布规律和变形特征,分析了结构的耗能机理,计算了相应的延性系数、承载力退化系数。试验表明,钢框架内填深梁之后,整体结构的初始刚度、极限承载力都有了明显提高,解决了纯框架结构抗侧刚度不足的问题。通过改变内填深梁的高宽比,可以实现从纯框架结构到框架剪力墙结构之间刚度的渐变提高。

Steel frame structures and steel frame-shear wall structures are two common lateral resisting systems,but the rigidities of these two structural systems are substantially different.A new type of lateral resisting system-steel frames filled with composite deep beams is proposed,which is between steel frame structures and steel frame-shear wall structures in rigidity.Two quasi-static tests on steel frame filled with composite deep beam and one test on steel frame are conducted.The effects of depth-to-span ratio of the composite deep beam on the hysteretic behavior of the frame are investigated.The hysteretic curves,the distribution of the stresses and the deformation configuration are obtained experimentally.The mechanism of energy dissipation is analyzed;the ductility parameters are calcuated and the capacity deterioration is examined.The tests show that the composite deep beam helps to increase the initial stiffness and ultimate bearing capacity of the frame.It is also found that adjusting the depth-to-span ratio of the composite deep beams can achieve the optimal combination of lateral stiffness,suitable earthquake-resistant capability and dissipate seismic energy capacity of the structure.