大跨度单索面组合箱梁斜拉桥扭转受力分析

采用空间杆系有限元法和剪力流理论分析了东海大桥主航道单索面斜拉桥的组合箱梁扭转受力特性。计算结果表明,成桥运营阶段的主梁扭转剪应力由风荷载控制设计,混凝土桥面板、钢箱梁斜腹板、底板的最大扭转剪应力达到容许剪应力的约30%,在单索面斜拉桥的设计中应当得到重视。

Torsional Analysis of Composite Box Girder of Long Span Single Cable Plane Cable-Stayed Bridge

The spatial link finite element method and shear flow theory are used to analyze the torsional behavior of the composite box girder of the long span single cable plane cable-stayed bridge of Donghai Bridge over the main navigable channel.The results of the analysis and calculation indicate that the torsional shear stress of the composite main girder at service stage of the completed bridge is governed by the design of wind load cases and the maximum torsional shear stress of the concrete deck slabs,steel box girder inclined webs and bottom plate can be as great as about 30% of the allowable shear stress of the structure,to which due attention should be paid in the design of the single cable plane cable-stayed bridge.