内部充水钢围堰的结构安全稳定分析

大型输水干渠边坡修复专用钢围堰是一种外动内静的水中钢构筑物，钢围堰在工作状况下结构稳定性十分重要。根据钢围堰的设计结构条件，考虑其在水中的动静荷载，进行流固耦合（FSI）系统的力学分析。首先分析钢围堰的荷载特征，将钢围堰绕流流场的复杂荷载条件简化为作用在结构上的流体压力；然后建立围堰结构的有限元模型。利用ANSYS数值模拟软件，研究各构件的受力状况及整体结构特性。结果表明：上游支撑杆件轴向应力大于欧拉临界应力，且导槽和面板变形量过大，需作结构调整，而中游和下游稳定性满足要求。通过结构优化调整，提出了结构改进方法，成功应用于工程实际，为钢围堰的优化设计提供理论支撑。

Structural safety and stability analysis of internal water-filled steel cofferdam

The appropriative steel cofferdam for slope restoration of a large aqueduct is a kind of underwater steel structure, moving externally and statoc internally, and its structural stability is fundamental under working conditions. According to the design structure condition of the steel cofferdam and considering its dynamic and static loads in water, the mechanical analysis of fluid-structure coupling (FSI) system is made. Firstly, the load characteristics of the steel cofferdam are analyzed, and the tanglesome load condition of the flow field around the steel cofferdam is simplified to the hydrodynamic pressure acting on the structure. Secondly, a finite element model of cofferdam structure is constructed. Numerical simulation software ANSYS is used to analyze the stress state of each component and the characteristics of the whole structure. Studies show that the axial stress of the upstream bracing piece is larger than the Euler critical stress, and the deformation of the guide groove and the faceplate is quite large, which requires structural adjustment, while the stability of the middle and downstream bracing piece meets the requirements. By optimizing and adjusting the structure, the method of ameliorating the structure is put forward, and is successfully applied in engineering practice, thus providing a theoretical support for ameliorating the design of the steel cofferdam.