Research On Crack Control Technology Of Mass Concrete In Gravity Anchor Structure

With the development of the times and the prosperity of the national economy,construction industry has developed rapidly in recent years,and mass concrete has also been widely used in various engineering fields.Because the cement in the concrete releases a lot of heat during the hydration reaction,and the concrete itself has a low thermal conductivity,the increase internal temperature of the concrete causes an excessive temperature difference between the inside and the outside,and finally the temperature cracks in the concrete are formed.Concrete temperature cracks are extremely harmful,not only affecting the durability of the structure,but also causing losses to people’s lives and property.Based on this,in this thesis,the Chongqing Changshou Yangtze River Second Bridge Project is used as a background to systematically study the temperature crack control technology of gravity anchorage mass concrete.The main research contents are:(1)Research on temperature control technology measures for large volume concrete.By analyzing the factors affecting the hydration heat of concrete materials and common temperature control measures,and using the finite element method to simulate the temperature distribution of concrete under different concrete material parameters and temperature control measures,so as to provide a reference for the determination of temperature control measures for mass concrete of anchorage.This paper mainly analyzes the influence of concrete cement dosage,specific heat capacity,elastic modulus,thermal conductivity,air temperature,linear expansion coefficient and pouring method on temperature stress,determines the influence law of each parameter on temperature stress of concrete materials,and puts forward corresponding temperature control methods.(2)Analysis of temperature stress inside the anchorage structure under different factors.Analyze the changes in concrete thermal and mechanical parameters,boundary conditions,initial conditions,and curing conditions that affect the temperature effect of anchor structures,summarize the effects of different factors on the hydration heat temperature effect of anchor blocks,and propose corresponding temperature control suggestions from a structural perspective.(3)Optimization of temperature control measures for anchor structures based on XGboost algorithm.In response to the problems of manual water cooling measures,an intelligent decision-making model for water supply is constructed based on numerical simulation,integrated algorithms,and particle swarm optimization algorithm,in order to achieve the most economical water supply strategy while meeting the requirements of structural temperature stress.