摘要
结合某超高层钢结构工程,针对该项目中拟采用的中厚壁、大直径钢管混凝土节点可能存在的层状撕裂问题进行试验研究。依据CECS28:90规范设计了两种不同构造的内置加劲环节点,对其进行的加载试验表明:该节点具有较高的承载力和变形能力,塑性铰出现在梁柱交接处,若焊接稍有缺陷则很有可能发生层状撕裂现象。在此基础上,提出了对梁端翼缘进行变截面扩展处理的改进型节点,并重新进行试验及相应的有限元分析。研究表明:改进型节点塑性铰位置明显偏离了节点区域,有效改善了节点的受力状况。按弹塑性非线性有限元分析得到的节点破坏形态、应力分布状况和极限承载力与试验实测结果基本吻合,证明工程设计所采用的分析理论符合节点的实际工作状况,所提出的变截面坡度为1∶1的小扩展形式构造措施可以避免层状撕裂的发生。
Based on a super high-rise steel structure project,which intends to use large-diameter,middle thickness steel tube filled with concrete,the paper studies of the possible lamellar tearing at connections.Firstly,two different connection specimens with inside strengthening rings were designed according to the design code.The results show that the connections are of high load-bearing and deformation capacity,but the plastic hinge appears in the intersection of the beam and the column.If the welding happens to have some minor defects,it will lead to lamellar tearing failure causing a great security risk for the structure.A new improved connection design was proposed,and the corresponding test study and finite element analysis were carried out.The results show that the plastic hinge location is obviously away from the intersection region,which has effectively improved the stress state of the connections.The failure mode of the connections,stress distribution and the load bearing capacity from elastic-plastic finite element analysis basically match with the test measured results,which shows that the analysis theory used in engineering design in line with the actual working conditions of the node.The suggested detailing design can avoid lamellar tearing failure in connections.
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2010年第11期111-118,共8页
Journal of Building Structures
基金
国家自然科学基金项目(10672039)
教育部科学技术研究重点项目(105083)
关键词
钢管混凝土
节点
中厚钢板
静力试验
层状撕裂
塑性铰
concrete-filled steel tube
connection
middle thickness plate
static test
lamellar tearing failure
plastic hinge
