初始缺陷对冷弯薄壁腹板开孔C形钢梁稳定承载力的影响研究  

Study on the effects of initial imperfections on stability bearing capacity of the web opening C-shaped cold-formed steel beam

作　　者：徐宏艳[1,2] 刘晶波[2] 

机构地区：[1]中国建筑设计研究院,北京100044 [2]清华大学土木工程系,北京100084

出　　处：《建筑结构》2013年第S1期439-442,共4页Building Structure

摘　　要：冷弯薄壁型钢构件在制作安装过程中将会产生一定的初始缺陷,包括几何初始缺陷和力学初始缺陷。采用ANSYS程序分析了几何初始缺陷、冷弯残余应力及两者综合作用对冷弯薄壁腹板开孔C形钢梁稳定承载性能的影响。根据算例分析得到以下结论和建议:对于破坏形式为跨中截面受弯破坏的开孔梁,局部初始缺陷对其承载力几乎没有影响,可忽略局部初始缺陷的影响;对于破坏形式为局部屈曲破坏的开孔梁,需要考虑局部初始缺陷的影响,可取0.005倍的腹板高度作为初始缺陷峰值进行计算。冷弯残余应力对构件极限承载力影响较小,使构件整体刚度和稳定性略有降低。C-shaped cold-formed steel beam will carry some initial imperfections during manufacturing process,including initial geometrical imperfection and cold-formed residual stress. Finite element analysis software ANSYS is used to study the influence of initial geometrical imperfection and cold-formed residual stress in bearing capacity of the web opening beam. According to the results,the following conclusion and propose are given: the initial geometrical imperfection should be included only when the failure mode is local buckling,and a peak value of the initial geometrical imperfection is suggested as 0. 005 times the web height. Meanwhile,stability bearing capacity is verified to be little influenced by the cold-formed residual stress.

关 键 词：冷弯薄壁型钢 腹板开孔 C形截面梁 稳定承载力 初始缺陷 残余应力 

分 类 号：TU392.1[建筑科学—结构工程]