Research On Related Problems Of Temperature And Stress Control Of Mass Concrete

With the rapid development of social economy, under the new situation of increasingly in complicated engineering structure, scientific and mass concrete is widely used in the field of water conservancy, transportation, construction, and many other fields as an important form of modern engineering structures. Because of the poor heat conduction performance, large casting volume, complex construction factors and external environment changing, mass concrete is easy to produce large temperature stress, even produce temperature crack that affect the safety of structure if superpose some other adverse factors. The study of mass concrete temperature field and thermal stress not only can improve the discipline of the research content but also can supple some necessary reference for practical crack control in concrete engineering.This paper introduces the features of mass concrete and the reason to cause temperature stress, on the basis of analyzing and summarizing domestic and foreign studies on this field, this paper elaborates the basic theory of mass concrete temperature control and the conventional algorithm, and then for the specific structure of mass concrete form, build the model of difference algorithm on fixed slab and free board, which can better realize the solution of the temperature and the temperature stress; building the model of self-equilibrating thermal stress by difference algorithm on plane, using the finite difference model for plane state to analyze the simulation of concrete temperature stress, good analysis and calculation results have been achieved;finally in view of the typical examples of large volume concrete pouring, system to the outside air temperature change of concrete simulation analysis was made on the influence of the temperature field and temperature stress, and the corresponding temperature control measures are put forward. The main contents and the results of this paper are as follows:(1) For basic theoretical model of mass concrete structure, fixed slab and free board, building the temperature field and temperature stress field of finite difference to solve the model, and the distribution and variation of temperature and temperature stress of solution are system analyzed, through comparing with the theoretical value,its results can meet the engineering need.(2)For the self-equilibrating thermal stress of concrete on plane condition, using the theory of mathematical difference, a model of self-equilibrating thermal stress is built by difference algorithm and is solved, the solving result is better, prove that the difference model is in the good adaptability in solving the concrete temperature stress.(3) The actual pouring mass concrete temperature field and temperature stress field is simulated, system studied and analyzed under the changing outside temperature condition, internal temperature of mass concrete and temperature stress change rule, and on this basis, providing the corresponding temperature control measures, and putting forward comprehensive evaluation and design thinking analysis in advance of the temperature control.Last, the results of this paper are summarized and the necessary technology outlook is put forward.