大型渡槽动力设计方法研究

根据大型渡槽结构的特点,在缺乏适用的抗震分析模型前提下,提出支撑-渡槽-水伪三维流固耦合动力分析方法。模型基于结构动力分析理论和流固耦合分析理论,整体结构分析采用Newmark方法进行动力时程分析,分析中考虑渡槽结构整体受力性能,包括下部支撑结构、地基等多种因素的影响作用;渡槽-水耦合体子结构分析采用任意拉格朗日-欧拉(Arbitrary Lagrangian Eulerian,ALE)有限元方法进行动力分析,考虑渡槽-水的耦合相互作用,模拟渡槽中水体的大幅晃动作用,相应得出渡槽中动力压力值及其分布。以某排架支撑矩形渡槽为例,采用本文提出的伪三维模型进行地震时程分析,计算结果与三维模型计算结果吻合良好。本文提出的伪三维动力分析方法计算效率高,满足渡槽结构抗震设计要求,便于工程应用,是大型渡槽结构动力分析研究和抗震设计的实用静、动力分析方法。

Study on dynamic analysis method of large aqueduct structures

Based on characteristics of large aqueduct structures and situations of lacking reasonable analysis method for seismic analysis of large aqueduct structures,pseudo three dimensional dynamic analysis method of high frame supported large aqueduct water coupling system is proposed,the theories of which are based on structural dynamic analysis and fluid structure interaction.Newmark method is employed in integral structural analysis,in which integral performances of load bearing of the aqueduct structure,including the effects of supports,foundation and so on are taken into account;while Arbitrary Lagrangian Eulerian FEM is employed to carry out dynamic analysis on aqueduct-water coupling substructure,in which aqueduct-water coupling effects and large water sloshing effects are considered,the value and distribution of hydrodynamic pressure can be obtained.A high frame supported rectangular aqueduct structure is analyzed by employing pseudo three-dimensional model,which yield much close results compared those using 3D finite element model.Therefore the pseudo three-dimensional dynamic analysis method is proved to be a practical static and dynamic analysis method for dynamic analysis and seismic design of large aqueduct structures with high efficiency.