半刚性梁柱节点连接的初始刚度和结构内力分析

给出了考虑节点半刚性连接的线性化模型初始刚度的计算公式,推导了半刚性连接在荷载作用下的内力计算公式,讨论了半刚性连接对框架内力的影响。通过分析表明,半刚性连接的初始刚度主要与连接件的抗弯刚度、板厚以及螺栓的分布位置有关。半刚性连接框架受连接柔性的影响,钢框架采用半刚性连接会使横梁的杆端负弯矩减少,而跨中正弯矩要相应增加,按刚性连接设计不符合实际受力情况。其结果将高估由梁端传到柱的负弯矩而低估梁的跨中正弯矩,框架的半刚性连接对结构受力性能有明显影响,在钢框架分析和设计中,应考虑半刚性的影响。

INITIAL STIFFNESS OF SEMI-RIGID BEAM-TO-COLUMN CONNECTIONS AND STRUCTURAL INTERNAL FORCE ANALYSIS

This paper is concerned with the initial stiffness of semi-rigid connections under linear assumption. The fixed-end moments of semi-rigid beams under concentrated, uniform and linearly varying loads are obtained. The influence of semi-rigid connections on the internal forces of steel frame is discussed. It is shown that the initial stiffness of semi-rigid connections is mainly related to the bending stiffness of the joints, thickness and location of bolts. The flexibility of the connections affects the behavior of the frame. It can decrease the negative end moment of beams and increase the positive moment at the mid-span of beams. Thus, it is unreasonable to design under rigid connection assumption. It is concluded that the semi-rigid connections should be taken into account in the analysis and design of steel frames.