偏心荷载作用下多室宽箱梁弯扭特性分析

通过建立不同箱室数量和宽跨比的单箱多室宽箱梁的有限元模型，分析了宽箱梁在扭转荷栽和偏心荷载作用下的剪力流和竖向位移分布。研究结果表明：多室宽箱梁整体扭转刚度大，扭转荷载作用下主要呈整体扭转变形；偏心荷栽作用下，多室宽箱梁弯扭效应由整体的竖向弯曲和整体扭转两部分组成；由于箱室宽度较大，偏心荷载作用下扭转剪力流效应明显．应重视各腹板剪力的不均匀分布。

Flexure and Torsion Characteristic about Wide Multi-Cell-Box Girder under Eccentric Loads

Some FEM models of box-girders with different number of cell and width-span ratio were established and calculated. Shear flow and transverse distribution of vertical displacement about muhi- cell box girder under the action of torsion loads and eccentric loads were analyzed. The results illus- trate： under the action of torsion loads, the torsional rigidity of multi-cell wide box girder is so high that whole section torsion deformation of girder become leading deformation; under the action of eccentric loads, the flexure and torsion effects about multi-cell wide box girder can be divided into two parts： the flexure deformation and whole section torsion deformation; the torsional shear flow is dominant because width of cross section of box girder multi-cell is too large, so the uneven distribution of shear in webs should be brought to the forefront.