高层有支撑钢刚架二阶弹塑性分析的改进P－△法

Second Order Elasto-Plastic Analysis of Tall Steel Braced Frames

采用文献［１］提出的改进Ｐ－△法，对１０层３４跨刚架进行分析，引用文献［２］的方法建立支撑（压杆）的荷载－位移曲线，包括其上升段与下降段，由轴向变形确定其轴力与割线模量．刚架分为强柱弱梁型和弱柱强梁型两种（柱截面尺寸相同），支撑采用单斜杆（压杆），根据不同的长细比和截面积，计算了３６榀刚架荷载－位移的全过程．作出了相应的荷载－位移曲线和弹塑性极限状态时的层间相对位移．

A parameter study of the elasto-plastic behavior of 10-story 3-span frames subjected to lateral loading is presented in the paper by using the improved P-△ method described in reference 1. The secant stiffness of the compression brace bar is determined from its load-deflection curve including ascending and descending parts of the curve which is established by using the method presented in reference 2. The frames analysed consist of two kinds of types, i.e.strong-column weak-beam type and weak-column strong-beam type. The slenderness ratio and cross sectional area of the bracing bars are adopted as parameters and 36 whole load-deflection curves of the frames are obtained and described in the paper.