基于结构动力分析理论和流固耦合分析理论，在已有的“拟三维”梁式渡槽建模方法的基础上，提出了“改进拟三维”梁式渡槽流固耦合建模方法。模型不仅能实现渡槽与大晃动水体的双向同步耦合，而且大大提高了计算效率，可用于多跨渡槽联合的流固耦合计算分析。除此之外，模型还可以用于计算带有加劲结构型式的渡槽。以东深供水渡槽的某段为例 , 采用提出的“改进拟三维”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，计算效率高。因此，提出的模型可以作为梁式渡槽分析计算的实用静、动力分析方法。

On the basis of the structural dynamic analysis theory and fluid structure interaction theory ， this paper puts forward the “ improved pseudo three-dimensional ” beam aqueduct computing mode replacing the existing “ pseudo three-dimensional ” beam aqueduct model. In this paper, the model can not only achieve two-way synchronization FSI(fluid structure interaction) of the aqueduct with large sloshing water, but also greatly improves calculating efficiency. So the model can be used for calculating and analyzing the joint multi-span aqueduct considering FSI. In addition, the “ improved pseudo three-dimensional ” can be used to calculate the aqueduct structure with a stiffening rib. One segment of Dongshen Water Supply Aqueduct is analyzed by employing “ improved pseudo three-dimensional model ”， which yields much close results compared those using 3D finite element model. Therefore ， the improved 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.