The Research On Temperature Stress Analysis And Crack Control Of Super-long Curved Frame Structure

With the rapid development of China's economy and the continuous improvement of urban construction level,"square box" type building has been unable to meet people's aesthetic needs,the beautiful appearance and practical curved building has been widely used.If the arc length is longer than the maximum spacing requirements of the "concrete structure design ",it will be defined as "super-long structure".At present,the research on the temperature stress of this kind of structure mainly concentrates on the long structure with rectangular rectangle,and the study on the long structure of the arc with curved shape is less.In this paper,the effect of temperature shrinkage effect of a super-long reinforced concrete frame with curved structure is selected,and the distribution law of temperature stress and the design method of crack control are discussed.The paper mainly studies the following aspects:(1)The elasticity theory and finite element method are used to analyze the effect of temperature on the structure.The shrinkage of the concrete is converted into the shrinkage equivalent temperature difference,and the seasonal temperature difference is taken into account.The temperature difference reduction coefficient is deduced from the age-adjusted effective modulus method considering the effect of concrete creep.(2)The finite element software Midas Gen is used to analyze the temperature effect of the super-long curved frame structure under the seasonal temperature difference.It is found that the super-long curved frame structure has a "whole bending effect" under the overall cooling effect.The deformation characteristics and the internal force distribution is different with rectangular frame structure.By changing the parameters such as curvature,lateral constraint,floor height and number of floors,the main influencing factors of the temperaturestress of super-long curved frame structure are explored.(3)The temperature effect of super-long curved structure under sunshine temperature difference is analyzed.The actual sunshine radiation temperature difference is decomposed into linear temperature difference and uniform temperature difference.By comparing the linear temperature difference,the uniform temperature difference and the equivalent linear temperature difference,it is found that the uniform temperature difference mainly affects the structural deformation,the linear temperature difference causes the internal force in the structure,and the linear temperature difference only affects the components under the sunshine radiation,so take good insulation measures,which can effectively reduce the impact of sunshine temperature.(4)Based on the distribution of the temperature stress of the super-long curved structure,the paper discusses how to realize the seamless design of the super-long curved concrete frame structure from three aspects: rational arrangement of structure,crack design of beam plate structure and structural crack resisting measure.The research results of this paper have some help to the design and construction of super-long curved concrete structure.