斜交单箱双室箱梁剪滞效应分析

运用ANSYS程序中的SHELL63单元,分析了集中荷载、均布荷载作用下不同斜度斜交单箱双室三跨连续箱梁剪滞效应的纵、横向分布规律.结果表明,斜交箱梁中支承断面剪滞效应的横向分布规律受斜交角影响很大,中支承断面在2种荷载作用下均出现负剪滞效应.分析斜交连续箱梁剪滞效应的纵向分布规律时,出现了明显的负剪滞效应,正负剪滞效应的分界位置是距斜交箱梁中支承中心断面1/4跨长处.斜交箱梁与正交箱梁的剪滞效应有很大不同,设计时必须充分考虑剪滞效应的影响.

Analysis of Shear Lag Effect of Single Box and Twin-cell Skew Box Girder

The SHELL63 unit of ANSYS program was used to analyze the longitudinal and transversal distributions of shear lag effect for single box twin-cell three-span continuous skew box girder with different degrees of skew under concentrated or uniform force. The results show that the distributions of shear lag effect of the cross-section Ⅱ- Ⅱ of skew box girder were affected by the skew angle greatly,and the negative shear lag effect was appeared under both the force. When skew continuous box girder were analyzed re- spectively to investigate longitudinal distributions of shear lag effect, there was a kind of phenomenon of negative shear lag effect, and the division position of the positive and negative distributions of shear lag effect was a quarter of the span length from the cross-section Ⅰ -Ⅰ of skew continuous box girder. A box girder was very different from an orthogonal box girder in the shear lag behavior, and the shear lag effect must be fully considered in the design of a skew box girder.