Stress Analysis And Flow Evolution Numerical Simulation Of Continuous Discharge Building

Cascade reservoirs are interrelated and mutually constrained.Once the upstream reservoirs are wrecked,they will have a serious impact on the downstream cascade reservoirs.Shi man tan dam and Tian gang reservoir are two retaining structures located in Gun River in the upper reaches of the Huai River and Hong River tributary river.Shi man tan dam belongs to the roller compacted concrete gravity dam.Tian gang dam belongs to homogeneous earth dam which the body can not be flowed over.The stress and strain performance of dam body is an important index to evaluate the safety of gravity dam.Studying the stress variation law of gravity dam under basic load and evaluating the safety of engineering structural have very important significance to study the threat from shi man tan reservoir flooding to Tian gang reservoir when the coming of very flood in flood season.In this paper,according to the working characteristics of RCC gravity dam and the basic theory of stress analysis of finite element method.The finite element analysis is carried out by using ANSYS Workbench software,and the simulation model of three-dimensional overflow dam section and non-overflow dam section of Shimantan gravity dam is established.On this basis the stress is analyzed;The mathematic model is established by solving the rectangular grid difference method of Saint-vennat equations,and then the flood discharge law and flood evolution of unsteady flow in lower reaches of Shi man tan reservoir is studied accordingly.The numerical simulation of flood evolution is carried out using MATLAB language.The main conclusions are as follows:(1)The static analysis of the dam uses the supercell segmentation technique to generate eight-node hexahedral elements automatically.The stress distributions of non-spill dams and spill dams are in accordance with the general rule in the design flood level,the check flood level and the flatting water level.That is,the maximum compressive stress of the dam appears in the dam toe,the maximum tensile stress(minimum compressive stress)appears in the dam heel,and the stress value increases with the increases of upstream water level.(2)The range of the vertical stress zone of the heel under the three kinds of calculated work condition of non-overflow sections is less than 0.07 times of the width of the dam.The results meet the specification requirements;The range of the vertical stress zone of the dam heel in the design flood level and the check flood level is also less than the specified value.However,the vertical stress stress range of the heel is 7.49% under the third condition,which does not meet the specification requirement.(3)Based on the flood discharge rules of the shi man tan reservoir.The mathematical model of the Saint-Vennat equations in differential scheme is established by using MATLAB programming and four iterations to find the initial conditions of the flood process line.And then calculating the flow curves and the water level of each section at each moment.(4)Using the engineering example,the flood evolution model is verified,and the analysis shows that the simulation value and the measured results have good applicability.