先简支后连续分布式箱梁桥后连续预应力合理张拉顺序研究

采用等效节点力的概念，以虚拟层合单元程序为平台，分析推导了预应力空间效应分析的方法，并以此为基础，考查了一座先简支后连续小箱梁桥后连续预应力张拉引起的结构空间效应。针对先简支后连续的施工特点，重点考查了结构在不同的后连续端浇注与张拉顺序下的预应力效应及其对结构受力的影响。结果表明，采用不同的张拉顺序，对于结构的受力和变形，尤其是临时支座的合理受力影响很大。并从中选择一次性浇注所有后连续端部的施工顺序作为最优的工序，推荐为施工所采用。

Research on Rational Post Successive Prestress Tension Sequence of Simply Supported and Continuous Box Girder Bridge

Based on the virtual laminated element theory and program, the concept of equivalent node force was adopt to make a program, with which the spatial effect induced by post successive pre-stress of a simply supported and continuous spread boxes bridge was analyzed. Then, by comparing the stress and displacement distribution of some key points in the box girder, the different effects induced by different wires tension sequences and their influences on the mechanical behavior of the structure were investigated particularly. The results show that the structural stress and deformation, as well as the support react force vary apparently with different concrete casting and wires tension sequences. The method that the post successive concrete are casted once only is found to be the most reasonable concrete casting. The wires tension sequence is recommended to be applied to the construction of bridges of the same kind.