翼缘-腹板削弱型梁柱节点受力性能影响因素分析

Research of factors which affecting the capability of flange-web reduced beam-column connection

"强节点弱构件"是保证结构抗震能力的重要一环,工程设计中一般采用"狗骨式"等方式实现。考虑到工程中管线纵横交错,管线往往需要横向穿越梁腹板,因此本文创新性地提出翼缘-腹板削弱型梁柱节点,即在削弱翼缘的基础上开孔削弱腹板,开孔形式为圆形。除开孔形式外,本文还通过ANSYS数值模拟,研究了开孔的不同位置、不同直径、不同面积对翼缘-腹板削弱型梁柱节点受力性能的影响。再通过荷载-位移曲线、塑性铰发展过程等指标,确定了该类节点的开孔原则。使得按照该原则进行设计建造的构件能够在保证应有承载力的情况下,较好地实现"强节点弱构件"的效果。研究发现:(1)翼缘-腹板削弱型构件的极限承载力与纯翼缘削弱型构件大致相同,既可以满足工程实际需求,又可以更好地实现"强节点弱构件";(2)腹板开孔数量对节点承载力影响较小,但可以有效促进塑性铰在梁端实现;(3)开孔中心距柱翼缘距离D对节点性能影响较大,当开孔距离为0. 6~0. 7倍翼缘宽度时效果最好。

"Strong-joint Weak-members" is vital to the capability of structure when it suffers from earthquake,which is achieved by reducing the section of beams. Considering that the openings may be asked to be circles and may be occurred on the web when the lines need to pass through members,a new connection,which is flange-web reduced connection with circular openings is puts forward.There is need to analysis the influence of opening shape to the capability of flange-web reduced connection. Besides,location of openings,radius,and area of all the openings can have different impacts on the"strong-joint and weak-members". With the method of ANSYS,the factors above are discussed,and are some rules put forward to get better openings to achieve "strong-joint and weakmembers"when the capability is assured. The results show that the reduced beam-column connection can achieve the goal when the needs of construction can be met. Besides,the distance from the openings to the connection has great impact on the capability of the structure,while the number of web openings and the number of openings when the area keeps the same are not the key factors.