多室鱼腹式箱梁剪滞效应分析

Shear lag effect analysis for multi-cell fish-bellied box beam

针对鱼腹式箱梁应力及剪滞效应分布状态与传统箱梁不同的问题,通过使用有限元软件进行模拟分析,研究了鱼腹式箱梁在自重荷载作用下的真实受力状态,分析了引起鱼腹式箱梁剪滞系数非常规分布的原因,并为此类箱梁的设计、建设提供了经验和参考.结果表明,在自重荷载作用下,鱼腹式箱梁剪滞效应明显;腹板的变形平衡条件不同、剪力分配不均、各腹板中性轴变化速率不等是鱼腹式箱梁剪滞系数非常规分布的主要原因.

In order to solve the problem that the distribution states of stress and shear lag effect of multi-cell fish-bellied box beam are different with those of traditional box beam,the simulation analysis was carried out with finite element software,and the real stress states under the self-weight load effect of fish-bellied box beam were investigated. In addition,the reasons for the un-normal distribution of shear lag coefficient of fish-bellied box beam were analyzed,which could provide the experience and references for the design and construction of the box beams. The results showthat under the self-weight load effect,the shear lag effect of fish-bellied box beam is obvious,and the main reasons for the un-normal distribute of shear lag coefficient of fish-bellied box beam are the different deformation balance conditions of webs,different shear distribution and unequal change rate of neutral axis of various webs.