钢-预应力混凝土连续组合箱形梁的整体性能分析

Research on steel-prestressed concrete composite continuous box-beam

视多室箱梁单位宽度为空腹桁架 ,取桁架的每根杆件为一平面梁单元 ,用三次插值函数描述其位移 ,单元节点位移参数用三次多项式表示为箱梁梁段单元节点位移参数的函数。这样箱梁梁段单元可分为翼板 (顶底板 )、腹板 (斜腹板 )、伸臂和横隔板单元。在进行有限元分析时将其直接迭加至总体刚度矩阵 ,编制相应的程序后可任意分析单箱多室、多箱多室及不规整的多种材料组成的组合箱梁。同时能分析箱梁的畸变、翘曲、局部变形、剪力滞后和荷载横向分布等。用本文编制的程序进行了一座复杂的钢 -预应力混凝土连续组合箱梁桥计算 。

In order to compute the out of plane displacement of the wall, cross sectional distortion and shear lag effect of box girder, the transverse Finite Strip Method have been employed to divide the unit width box girder as a vierendeel truss, whose section is consisted of box girder elements. Each truss rod is described by Hermitian interpolations, in which the nodal displacements content of a plane beam are described by the three order polynomials as those of the box girder elements. The program can be able to analysis multi box girder and composite box beam.The computed result conforms to the bridge practice conception.