Inversion Analysis And Feedback Research On Temperature Field Of Mass Concrete Based On Genetic Algorithms

With the development of national economy, more and more the anchorage of suspension bridges, dams and others mass concrete structures construction. Because of concrete hydration fluid, constraint condition and environment temperature and humidity to cause the cracking of concrete problems are brought to the attention of the people. According to the crack problem, this paper introduces the type of cracks in mass concrete, causes and detriment, and put forward the corresponding control crack measures. This paper introduced the related research based on the foundation of bulk cable saddle of Puli large bridge.The internal of the mass concrete temperature field and stress field is extremely complex, simulation of thermal parameters selection is a difficulty. In this paper, firstly, the temperature field inversion analysis model is established based on Midas/FEA, inversion of thermal parameters and the objective function. Secondly, write genetic algorithm program by using Matlab. Finally, according to the measured temperature data and using the program inversion to get the maximum adiabatic temperature rise of concrete, the reaction speed, surface exothermic coefficient and thermal conductivity.Further feedback research the foundation of bulk cable saddle. Firstly, through the concrete foundation of representative points between measured and calculated temperature contrast analysis, both are in good agreement. Verify the reliability of the program and parameter inversion can be accurately reflect the thermal properties of concrete. This paper made deep research of distribution and the law of development of temperature field in the casting, and based on this, advances some temperature control measures, for the theory reference significance for similar projects in the future. Secondly, choose nine characteristics of representative points to study creep stress field of bulk cable saddle foundation, it is concluded that the stress distribution situation, the law of development, the maximum time and the cracking of area. And based on this, put forward some control measures of temperature stress. Thirdly, studying deformation mechanism of bulk cable saddle foundation after pouring, get the maximum deformation of area and the influence of constraint conditions on the deformation. Finally, change the parameters of pouring temperature, surface exothermic coefficient and cooling water flow rate to analyze the effect of temperature field and stress field of the bulk cable saddle foundation, it is concluded that the influence mechanism of temperature field and stress field, and puts forward some reduce the pouring temperature and the measures for decreasing the surface exothermic coefficient.By studying temperature field, creep stress field and deformation of the foundation shows that mass concrete casting is the easiest cracking during the early and the upper concrete pouring. So we should reduce the pouring temperature during concrete pouring, strengthen maintenance in this time and control on the lower temperature and improving constraint conditions as soon as possible to avoid concrete cracks.