Research On Temperature Fields And Stress Fields And Temperature Control Measures Of Mass Concrete

Mass concrete is widely used in water conservancy,traffic,construction and other fields.Studying the temperature field,temperature stress and temperature control measures of mass concrete can provide necessary reference for engineering practice.This article takes Chongqing Wanzhou Fuma Yangtze River Bridge as the engineering background,selects the north shore gravity anchorage large volume concrete as the research object,and combines ANSYS finite element software to study the temperature field and temperature stress field of mass concrete,and analyzes the temperature control measures.The main research contents and results are as follows:(1)The basic concepts of mass concrete are described,and the research status of mass concrete at home and abroad is summarized.Explain the concept of temperature cracks and analyze their causes.The basic theory of temperature field and temperature stress field of mass concrete is systematically summarized.(2)From the aspects of design,raw materials,construction,and strengthening of monitoring,specific measures for temperature control and crack prevention of mass concrete are proposed;and the economics of adding three kinds of temperature control measures to mass concrete,adding ice,burying cooling water pipes,and optimizing the mix ratio are carried out.Analysis and comparison show that the economics of adding ice to the three temperature control measures are relatively the worst.The measures to add cooling water pipes to reduce the internal temperature of mass concrete are more economical than adding ice,but it will extend the construction period.By optimizing the mass concrete The means to reach the temperature control target with the composition ratio not only has obvious temperature control effect,but also can save the engineering cost to some extent.(3)The concrete temperature control measures used in the mass concrete construction of the gravity anchorage of the Chongqing Gengma Changjiang River Bridge are summarized,including the optimization of the concrete mix ratio,the layered block pouring,the embedded cooling water pipe,and the heat preservation and maintenance control.Comparison with similar projects can provide reference for future actual projects.The difference curve method was used to calculate the temperature rise curve along the thickness of the foundation of the pier,and compared with the actual measured data.(4)Taking the gravity anchorage large-volume concrete on the north bank of Chongqing Fuma Changjiang River Bridge as the research object,ANSYS finite element software was used to simulate the mass concrete pouring process,and the numerical simulation results were compared with the actual measured values and theoretical calculation values.The simulation results show that using ANSYS finite element software to analyze the temperature stress field of mass concrete is feasible.The finite element software ANSYS was used to simulate the mass concrete placement under different working conditions(different injection temperatures,different mix ratios,and different insulation materials).The results were compared and analyzed,and corresponding temperature control measures were proposed.