大尺度开孔钢梁性能的试验研究和数值分析  

Experimental and Numerical Study on Behavior of Steel Girders with Large Web Openings

作　　者：童乐为[1] 宋涛炜[2] 江蓓[3] 王经俞[3] 

机构地区：[1]同济大学土木工程学院,上海200092 [2]中国建筑西南设计研究院,四川成都610081 [3]上海华东建筑设计研究院有限公司,上海200041

出　　处：《同济大学学报（自然科学版）》2008年第8期1050-1056,共7页Journal of Tongji University:Natural Science

摘　　要：研究了超出我国设计规范构造尺寸限制的大尺度、非等间距腹板开孔的钢梁性能,进行了2榀针对实际工程的长9 m钢梁的足尺静力试验,将试验数据与一般梁理论、空腹桁架理论、有限元等方法得到的计算数据进行了比较分析.研究表明:这种大开孔钢梁只要设计得当,能够满足承载力和挠度要求;空腹桁架理论适用空腹截面正应力的简化计算;孔口附近的实腹截面应力分布受到开孔的显著影响,对正应力和剪应力分布,有影响的范围为距离孔口边缘分别约0.9倍孔口高度以内和1.0倍梁截面高度以内;在影响范围之内,正应力呈非线性分布,中和轴处的剪应力偏大,与梁理论有关弯曲应力和剪应力公式的计算结果相差较大.An investigation was made of the behavior of steel girders with large and non-equidistant web openings of a size greater than the size limit of design specification of China. Full-scale static tests on two steel girders of 9 meters long were carried out for a real engineering project. Experimental data were compared to the numerical data obtained from basic beam theory, Vierendeel truss theory and finite element method. The present study shows that the girder with large openings can meet the requirement of load capacity and deflection as long as it is well-designed. The Vierendeel truss theory is suitable for the simplified calculation of normal stresses along a perforated cross section. The stress distributions along an unperforated cross section near an opening are significantly influenced by the layout of opening. The influencing ranges from the edge of an opening are within about 0.9 times the height of opening for the normal stress distribution and within about 1.0 times the height of girder cross section for the shearing stress distribution. Within the influencing ranges, the normal stress presents nonlinear distribution and the shearing stress at the neutral axis is much higher, which are quite different from the results of calculations based on bending and shearing stress formulas of beam theory.

关 键 词：开孔钢梁 足尺试验 应力分布 挠度 空腹桁架理论 开孔对应力的影响 

分 类 号：TU317.2[建筑科学—结构工程]