钢-混凝土连续组合梁腹板局部屈曲分析

对连续组合梁负弯矩区钢腹板的稳定性进行了研究，分析了负弯矩区钢梁腹板在弯曲、轴向压力和剪切作用下的力学性能，提出了组合梁腹板在各种荷载作用下的局部稳定性简化计算模型，建立了非均匀受压、纯剪和弯剪复合受力状态下的临界屈曲应力计算公式；分别计算了钢梁腹板在非均匀受压和纯剪状态下的弹性屈曲系数，并根据偏心受压与剪切作用下的相关方程计算了钢梁腹板在复杂应力状态下的弹性屈曲系数；基于屈曲分析结果，提出了组合梁在弹性受力阶段钢梁腹板不设横向加劲肋的高厚比限值。结果表明：采用该方法确定的钢梁腹板高厚比更具合理性，且计算过程简单，结果偏于安全。

Local Buckling Analysis of Web of Continuous Steel-concrete Composite Beam

The stability of steel web in negative moment area of the continuous composite beam was studied. The mechanical behaviors of steel web in negative moment area under the load of bending, axial pressure and shear were analyzed, and a simplified model for calculating the local stability of web of composite beam under different loads was proposed, and formulas were also formed for calculating critical buckling stress under the load of non-uniform compression, shear and complicated stress loads of bending and shear. The elastic buckling factors under the load of non-uniform compression and shear were separately calculated. The elastic buckling factor under the complicated stress load of bending and shear was calculated according to interaction equation of eccentric compression and shear. Based on results of the buckling analysis, the limiting height to thickness ratio was also determined for webs without stiffening ribs in the elastic stage based on the critical buckling load. The results show that the method is more reasonable for determining height to thickness ratio of steel web of beam, and the calculating process is simple, the result is on safe side.