外包角钢加固震损型钢混凝土节点试验研究

Experimental research on seismic behavior of angle steel-strengthened seismic-damaged joints in a composite frame of SRC columns and RC beams

为研究外包角钢加固震损型钢混凝土柱—钢筋混凝土梁组成的框架节点抗震性能,按1∶2缩尺比例设计并制作了5个型钢混凝土柱—钢筋混凝土梁组成的框架节点模型。其中1个为对比节点,1个为外包角钢加固节点,另外3个为模拟不同地震损伤后采用外包角钢加固节点,对所有节点模型进行低周往复加载破坏性试验。通过试验和测试参数分析可知:外包角钢加固型钢混凝土柱—钢筋混凝土梁组成的框架节点,保证了"强柱弱梁"抗震设计目标,破坏形态均为梁端弯曲破坏;采用外包角钢加固后的试件模型极限承载力、初始刚度和延性系数最大值分别提高了53.7%、47.1%和25.5%。在一定的损伤程度下,外包角钢加固震损型钢混凝土柱—钢筋混凝土梁组成的框架节点是一种有效的抗震加固方法。

In order to study the seismic behavior of angle-steel-strengthened earthquake-damaged joints in a composite frame of steel reinforced concrete(SRC)columns and reinforced concrete(RC)beams,five one-half scaled models of the joints were designed and manufactured.Among the models,one was the prototype control specimen,another one was strengthened by angle steel,and others were pre-damaged and reinforced by angle steel.The destruction tests on the models under lateral cyclic load were carried out.The result analysis shows that the joints can meet the strong column,week beam design requirement,and the failure modes of all joints are the flexural failure of beam.The ultimate bearing capacity,initial stiffness and ductility coefficient of the specimen strengthened by angle steel increased by 53.7%,47.1%and 25.5%,respectively.Under certain damage degree,it is an effective method to reinforce the seismic-damaged joints with angle steel in composite frames consisting of SRC columns and RC beams.