Stress Analysis And Crack Control Of High Strength Concrete In Shear Walls Of High-rise Tube Structure Buildings

Nowadays, High Strength Concrete(HSC) is more and more widely used in high-rise tube structure buildings. In HSC, more heat is produced during hydration than Normal Strength Concrete(NSC) due to its large quantity of cement in mix design. With super-long shear walls, stronger restraints and use of the HSC, thermal cracking often appears at early age in high-rise tube structure buildings. Consequently, it is required to know the variation regularity of temperature field in the structural member and thermal stress in order to make thermal crack controlled. This thesis reviews the current status on the research of the thermal stress in concrete at early age and of the HSC, the discussion of affecting factors about the structural thermal stress and the experimental tests on mechanical properties of the HSC at early age and of the method of reducing adiabatic temperature rise of the HSC are reported. The three-dimensional finite element analysis is deduced to study the unstable temperature field and thermal stress.According to the characters of the high-rise tube staicture buildings and the condirions of the real projects, a numerical simulation is performed to analyze the temperature field and thermal stress of the HSC shear walls, and by the simulation, a fundamental regulation is found. During the simulation, the results almost coincide with the site data. At the end, according to the analysis, trial measurements of crack controlling are presented.The paper can be used to determine the parameters in simulating the thermal stress of the HSC at early age. And the analysis results make the distribution of temperatureand thermal stress in the HSC shear walls clear, consequently, it can help us make out crack-controlling measurements. Finally, the trial measurements of crack controlling of HSC shear walls in high-rise tube structure buildings provide us some reference value in engineering...