罕遇地震作用下某超限钢结构建筑转换桁架复杂节点有限元分析

Finite Element Analysis of Complex Joints of Transfer Truss of an Transfinite Steel Structure Building under Rare Earthquake

为了研究某超限钢结构建筑转换桁架复杂节点在罕遇地震作用下的性能,采用ABAQUS软件对转换桁架关键节点进行拟动力作用下的应力分析和节点极限承载力分析。结果表明:除各构件局部接触角部位置达到屈服强度,进入塑性外,节点其他区域Mises应力明显低于材料屈服强度,节点整体基本保持弹性状态,未出现明显的塑性开展,满足罕遇地震作用下的性能目标;极限破坏时,构件区域先于节点区域破坏,且各节点设计均满足安全储备要求。可见,本工程的节点设计将节点隔板和加劲钢骨作为主要传力构件,采用等效面积原则来保证节点承载力大于进入节点的各构件承载力之和,保证了“强节点、弱构件”的结构设计要求。

In order to study the performance of complex joints of an transfinite steel structure building under rare earthquake,the finite element software ABAQUS was used to simulate the stress and destruction effect under ultimate load of key joints of transfer truss.The results show that:the Mises stress in other areas of the joint is significantly lower than the yield strength of the material,except that the local contact angle of each component reaches the yield strength and enters into plasticity.The whole joint basically keeps elastic state without obvious plastic development,which meets the performance target under rare earthquake.When the ultimate destruction occurs,the component area is destroyed prior to the node area,and the design of each joint meets the requirements of safety reserve.It can be seen that in the joint design of this project,the joint diaphragm and stiffening steel frame are taken as the main load transfer components,and the equivalent area principle is adopted to ensure that the bearing capacity of the joint is greater than the sum of the bearing capacity of each member entering the joint,and the structural design requirements of strong joint and weak member are ensured.