Shape Optimization And Simulation Analysis Of Temperature Stress Field For Hollow Dam During Construction Process

Because of lower uplift pressure,reduce concrete quantity,for cooling during theconstrction process.Hollow dams are widely used in both at home and abroad.However,the dam type of related research is still deficiency.First,the optimization design of hollow dams is still in the phase of scheme comparison,there is further optimized space;Second,its easy to never pay more attention to the characteristics of heat dissipation,the construction process simulation analysis also has been in a blank.In recent years,the application of roller compacted concrete is more and more common,the construction technology used in hollow gravity dam has become an inevitable trend.So this article to RCC hollow gravity dam as the research object,using ANSYS software platform,considering influence factors such as temperature,the RCC construction characteristics.On the one hand,put forward the optimum structure of hollow gravity dam forms,on the other hand,through the construction process of thermal-stress coupled field simulation analysis,explores the use of heat dissipation effect on the cavity.This paper is divided into five chapters,from theory to practice.The first chapteris introduction,mainly to the thesis research background,research significance,research contents,research methods and research framework for integration.The second chapter for the simulation analysis theory were reviewed.The third chapter is based on the complicated ventral hole form of hollow gravity dam,to establishmcomplete expression optimization mathematical model of each typical sections with the help of ANSYS optimization module,ventral holes on optimization of structural parameters for one-off,to determine the optimal cross section type and structure size;The fourth chapter,based on optimization of the construction process simulation,the coupled temperature and stress field,under the condition of the same entity gravity dam as a reference,comparedthe hollow gravity dam than entity gravity dam cooling effect,dam body temperature field under different temperature conditions on the cavity during the construction change rule;The fifth chapter is the conclusion of this paper summarizes research results.The main results were as follows:(1)hollow gravity dam type door,fan and inclined wall all upstream and downstream to upstream slope type 3 kinds.ANSYS optimization module of the above section optimization.The results showed that both upstream and downstream inclined wall to the layout of the upstream slope type make to the same as the direction of dam body internal force on the cavity,significantly improve the stress of the surrounding conditions on the cavity,on the basis of guarantee the specification requirements,played a material performance more effectively.Declined about 13.6% after optimization,sectional area,optimize the section inclined wall and upstream and downstream water levels of 72~76 degree Angle.In based on the results of optimization,set up five kind of dam foundation parameters,different dam under the condition of optimizing control conditions and the change rule of cross section,for different geological conditions of dam section size is selected to provide the reference.(2)according to practical engineering data,to optimize the dam construction whole process simulation calculation of the section,after considering the factors such astemperature and dam layer,using the finite element numerical analysis simulating theconstruction process of the change of the temperature field.Comprehensive construction in the process of dam body weight,the change of elastic modulus of concrete,pouring construction process simulation dam,discuss the influence of the temperature field of dam body stress during the construction.With same construction under the condition of no ventral holes entity gravity dam as a comparison,and analysis to summarize characteristics of hollow gravity dam is more conducive to heat dissipation.The results is showed that the hollow gravity dam construction is completed within the highest temperature of 28.88 degrees,compared with the entity gravity dam by 5.56 degrees.After the construction period entity biggest tensile stress of the dam 0.613 Mpa,hollow dam0.354 Mpa,0.259 Mpa.Hollow dam due to the cooling performance is good,the internal temperature is low,and contact with the bedrock area is lesser,and the stress state of construction entity gravity dam is more ideal.And hollow gravity dam stress mainly appears in the hollow crown,in the actual project should be through reinforcement engineering measures such as strengthening processing.To control temperature as the temperature control measures on cavity,set different schemes,the simulation calculation and analysis of the differences between each scheme and the influence degree of the dam body,sums up the economic and effective temperature control method.In this paper,the main innovation points: 1.Established the contains a variety of typical sections of hollow gravity dam of general mathematical optimization model,consider the temperature load and the dam in the process of optimization and the bedrock of the contact problem,and with the structure analysis of slag hollow gravity dam filling in.2.Analyzing the characteristics of the concrete hollow gravity dam are summarized to facilitate heat dissipation effect,and for the first time using hollow structure of the cooling as a dam temperature control measures are put forward.