组合框架梁负弯矩区有效翼缘宽度分析

Analysis of effective flange width of composite frame beam in negative bending moment area

采用有限元分析方法,考虑了宽跨比、板厚和抗剪连接程度等因素的影响,对静载作用下的组合框架梁负弯矩区的有效翼缘宽度进行了分析,并与我国规范GB50017-2003、欧洲规范EC4和英国规范BS5950计算结果进行比较.结果表明,按我国规范GB50017-2003方法计算组合框架梁负弯矩区有效宽度不够准确,尤其对负弯矩区弹性阶段的有效宽度取值偏高.而按欧洲规范EC4和英国规范BS5950的计算方法取值则偏于保守.

The effective flange width of composite frame beam in the negative bending moment area is analyzed by nonlinear finite element method considering the ratio of width to span, thickness of concrete slab and degree of shear connection under static load. The results of calculation are compared with the GB50017-2003, Eurocode 4 and BS5950. The result shows that GB50017-2003 is not precise enough for calculating effective flange width of composite frame beam in negative bending moment area; especially in the elasticity period the effective flange width of negative bending moment area will be on the high side. The effective flange width calculated with methods in Eurocode 4 and BS5950, is conservative.