工字形截面压弯杆的平面外弯扭屈曲  

OUT-PLANE FLEXURAL-TORSIONAL BUCKLING OF TAPERED BEAM-COLUMN

作　　者：李兰香 童根树[2] LI Lanxiang;TONG Genshu(China Shipbuilding NDRI Engineering Co.Ltd,Shanghai 200063,China;Institute of High Performance Building Structures and Materials,Zhejiang University,Hangzhou 310058,China)

机构地区：[1]中船第九设计研究院工程有限公司,上海200063 [2]浙江大学高性能建筑结构与材料研究所,杭州310058

出　　处：《工业建筑》2018年第7期140-145,共6页Industrial Construction

摘　　要：对受不等弯矩作用下的楔形变截面受弯构件进行平面外弹塑性分析,同时考虑初始缺陷和两种典型的残余应力模式的影响。取小端截面和大端截面的最大应力比值Kσ分别为-1.0、-0.5、0、0.5和1.0,考虑截面塑性开展,引入通用长细比,在通用长细比中考虑了楔率和弯矩变化的影响,拟合得到了新的弯扭屈曲稳定系数公式。对于变截面压弯构件的平面外稳定,提出了弯矩项带指数的光滑曲线相关公式,轴力项和弯矩项均取自大端的内力及其截面性质,弯矩项的稳定系数来自新的弯扭屈曲稳定系数公式,弯矩项的指数考虑了小端和大端截面应力比Kσ的影响,与ANSYS有限元程序结果进行了对比,发现所提公式的精度很好。Out-plane elastic-plastic analysis was carried out for tapered members which were effected by non-uniform moments,considering initial imperfection and two residual stress modes. The maximum stress ratio between the smaller end and the larger end was taken as-1. 0,-0. 5,0,0. 5 and 1. 0,and a new formula of stability coefficient was proposed,considering plasticity development and introducing the universal slenderness of beams in which the taper ratio and moment ratio were considered. For the out-plane buckling of tapered beam-column,another new formula was proposed in which the axial force and moment and sectional properties were taken from the larger end of tapered members,and the moment term in the formula took an exponent that varied with the maximum stress ratio slightly. The accuracy of the proposed formulas was verified by comparing with the ANSYS results.

关 键 词：变截面构件 弹塑性 平面外 弯扭失稳 非均匀弯矩 

分 类 号：TU391[建筑科学—结构工程]