马来西亚槟城二桥斜拉桥横隔梁的设计计算方法

Design and Calculation Method for Diaphragm of The Second Penang Bridge in Malaysia

马来西亚槟城二桥工程是采用英国标准的桥梁设计施工总承包工程,其主通航孔桥为主跨240m的肋板式主梁混凝土斜拉桥,设计采用悬臂浇筑施工。设计分析发现施工过程中已浇主梁梁段影响后续施工梁段横隔梁的受力和变形,后浇梁段横隔梁的结构自重、横隔梁预应力钢束和斜拉索张拉影响已浇梁段横隔梁的内力。为合理指导肋板式混凝土主梁横隔梁的设计,提出能准确反映这种横隔梁受力模式的实用计算方法——考虑施工过程的空间梁格法。应用表明,该方法可真实、动态地模拟横隔梁各施工阶段受力,避免简化方法的设计不足。

The Second Penang Bridge project is packed up within a general contract of bridge design and construction following the British Standard. The part of the Bridge over the main nav- igational channel is a concrete cable-stayed bridge with a main span of 240 m, and the ribbed slab main girder is designed to erect by way of cantilever cast. However, the de,;ign analysis shows that the already-cast segments of the main girder are liable to affect the mechanical behavior and the deformation of the diaphragms of the late-cast segments, and in reverse, vhe dead-load of the diaphragms of the late-cast girder segments, the prestressed tendons in the diaphragms and the tensioning of stay cables are possible to influence the internal force of the diaphragms of the al- ready-cast girder segments in the construction process. Therefore, to guide the design of the dia- phragms of the ribbed plate concrete main girder, the space beam grillage method, a practical cal- culation method which takes into consideration of construction process and is able to correctly re- veal the performance mode of the diaphragms, is proposed. The application of the method demon- strates that the method can practically and dynamically simulate the mechanical behavior of the di- aphragms in its various construction stages and avoid the design deficiency of a simplified method.