3D-FEM Analysis Of Prestressed Pier On Spillway Dam

With the current rapid development of hydroengineering in our country, station number and size have been growing rapidly. With increasing improvement of working head of discharge structures, discharge capacity and orifice sizes, hydraulic thrust delivered by arc working gate increases. Existing research results show that the arc-gate thrust near Pier neck trunnion will produce 5～8MPa of tensile stress. It’s very dangerous for pier whose size cannot be too large. In order to improve the working conditions of the support structure, to ensure discharge structure being safe, arranging a certain number of prestressed anchor cable in pier to control the tensile stress in the permissible range is the most effective way.Taking a practical pretressed pier on spillway dam for the study, using the finite element software ANSYS to build a three-dimensional finite element calculation model of prestressed pier, calculating and analysing the stress distribution law of prestressed pier in specific conditions, this paper puts forward the characteristics of stress on key parts of prestressed pier.This paper selects two conditions to calculate. Through comparing the stress calculating results, it determines case 1 being controlled condition, also using prestressed structures can improve the pier neck stress state. On this basis, through optimizing the main anchor tonnage, second anchor position, pier structure size, cavity layout of anchor block structure, contact way between bottom of anchor block and pier, it initially identifys structure form of the anchor block and anchor arrangement, provided reference for recommended solutions of presThe research results provide important reference value for the structural design of prestressed pier of this hydropower station engineering, some of the results have been applied in the design.