钢管混凝土柱-波纹腹板H形钢梁栓焊混合加腋节点抗倒塌能力研究

RESEARCH ON THE ANTI-COLLAPSE CAPACITY OF CFST COLUMN-CORRUGATED WEB H-SHAPED STEEL BEAM HAUNCH JOINT WITH HYBRID BOLTED WELDING CONNECTION

  • 摘要: 该文基于ABAQUS/Implicit建立了钢管混凝土柱-H形钢梁栓焊混合节点抗连续倒塌数值模型。为提高该类节点的抗倒塌承载力,采用了波纹腹板H形钢梁和下翼缘加腋构造。分析该类节点在竖向荷载作用下的破坏特征和失效机理,并考虑波纹腹板的“折叠效应”对节点抗倒塌能力的影响。研究结果表明,钢管混凝土柱-平腹板H形钢梁节点(J-WB-O)的破坏出现在环板和钢梁连接位置,而钢管混凝土柱-波纹腹板H形钢梁加腋节点(J-CW-AP)的破坏远离环板与钢梁连接位置,延缓了钢梁下翼缘断裂;此外,J-WB-O节点钢梁全截面提供倒塌抗力,而J-CW-AP节点在加载初期波纹腹板几乎不提供倒塌抗力,当下翼缘断裂后波纹腹板开始受力,并且随着裂缝的向上延伸波纹腹板截面依次呈现受拉状态,表现为波纹腹板波纹逐渐拉开的过程即为“折叠效应”,延缓了腹板开裂和局部屈曲。对比普通栓焊混合节点J-WB-O,波纹腹板H形钢梁栓焊混合加腋节点J-CW-AP的极限承载力与延性分别提高了67.2%和62.3%。基于抗力机制分析,给出了钢管混凝土柱-波纹腹板H形钢梁栓焊混合加腋节点抗倒塌承载力简化计算公式。

     

    Abstract: Establishes a numerical model using ABAQUS/Implicit for analyzing the progressive collapse of concrete-filled steel tubular (CFST) column to flat web H-shaped steel beam joint. In the joint configuration, a corrugated web steel beam and a welded haunch were employed to improve the anti-collapse capacity. The failure mode and failure mechanism of the joints under vertical loading and the folding effect of the corrugated web are analyzed. The results show that the failure of CFST column to flat web beam joint (J-WB-O) started at the connection between the ring plate and the beam, while the initial failure of the CFST column-corrugated web beam haunch joint (J-CW-AP) appeared at the end of the welded haunch, which delayed the fracture of the lower flange of the beam. Moreover, for the specimen J-WB-O, the entire beam section contributed to anti-collapse capacity. For the specimen J-CW-AP, the corrugated web seldom contributed to anti-collapse capacity in the initial loading stage. After the fracture of the bottom flange of the specimen J-CW-AP, the corrugated web began to contribute to anti-collapse capacity. As the cracks propagated upwards, the sections of the corrugated web were under tension gradually. The fracture and local buckling of the web were delayed due to the folding effect of the corrugated web. Compared with the specimen J-WB-O, the bearing capacity and ductility of the specimen J-CW-AP increased by 67.2% and 62.3%, respectively. Furthermore, a simplified calculation method of anti-collapse capacity is proposed based on the analysis of resistance mechanism.

     

/

返回文章
返回