双室混凝土箱梁桥横向弯曲分析的简化方法

SIMPLIFIED METHOD FOR TRANSVERSE BENDING ANALYSIS OF DOUBLE CHAMBER CONCRETE BOX GIRDER BRIDGE

箱梁桥是跨度超过25 m的桥梁的最佳选择之一,对于这些桥梁的研究,三维有限元分析是最合适的方法,然而,在常规设计中进行三维分析既困难又耗时;此外,用于三维分析的软件非常昂贵,因此,设计人员采用简化分析,以预测纵向和横向弯矩,在众多用于求横向弯矩的分析方法中,简化框架分析(SFA)是最简单且在设计室中应用最广泛的一种。简化框架分析的结果可用于混凝土箱梁桥的初步分析,从文献回顾中可以发现,目前采用SFA所做的大部分工作仅限于对单箱单室梁桥的分析,对多室混凝土箱梁桥的分析工作做得不多。本研究选择了一座双室混凝土箱梁桥,使用三维有限元软件对桥梁进行建模,然后将结果与简化的框架分析进行比较,该研究的重点是建立SFA得到横向弯矩值的修正因子。

The box girder bridge is one of the best choices for bridges with a span of more than 25 m.For the study of these bridges,three-dimensional finite element analysis is the most appropriate method.However,three-dimensional analysis in conventional design is difficult and timeconsuming;in addition,the software used for three-dimensional analysis is very expensive.Therefore,designers use simplified analysis to predict the longitudinal and transverse bending moments.Among many analysis methods used to calculate the transverse bending moments,SFA is the simplest and most widely used in the design room.The results of the simplified frame analysis can be used for the preliminary analysis of concrete box girder bridges.From the literature review,it can be found that most of the work done by SFA at present is limited to the analysis of single box and single cell girder bridges,and little is done to the analysis of multi cell concrete box girder bridges.In this study,a double cell concrete box girder bridge is selected,and three-dimensional finite element software is used to model the bridge,and then the results are compared with the simplified frame analysis.The focus of this study is to establish the correction factor of SFA to obtain the transverse bending moment value.