Study On Initial Stress Accumulation Process For Construction Of Steel Reinforced Concrete Transfer Floor Under Layer By Layer Method

SRC(steel reinforced concrete)transfer truss structure is one of the most competitive structural types in the modern transfer layer structure,which is belonging to the combination structure of steel and concrete.Before the composite material structure becomes a common joint,the different construction methods will result in different initial stresses in the structure.The existence of initial stresses will affect the bearing capacity of the structure.In this paper,"Liu Dong New Area enterprise headquarters office building project" was used to be the engineering background,according to the overall hoisting of the steel truss and the layer-by-layer construction process based on the theoretical analysis and construction site test study in order to study the methods and the accumulation process of initial stresses.Meanwhile the lattice column support system which affects the initial stress of transfer truss structure take on Midas/Gen finite element simulation analysis.In the process of construction,the main part and key members of the conversion truss conduct real-time monitoring of the construction site in order to ensure that the safety and reliability of construction process.The main contents and work of this paper are as follows:(1)The development process and current situation of steel truss structure and construction simulation are fully summarized,and the layout type and stress characteristics of truss structure are also analyzed.(2)Firstly,the theory of stress and deformation is analyzed and studied by means of Midas/Gen finite element method for the whole hoisting process of steel truss.At the same time,the steel trusses are monitored in real time in the whole hoisting process,and the method of comparative analysis is useed to analyze and contrast the theoretical and practical values.(3)As changing the stiffness of the support system has some influence on the initial stress of the structure,Midas/Gen finite element simulation is carried out for the lattice column support system in order to analyze the results of the initial stress of the truss when the stiffness change of the support system.Considering the cross section type and bearing capacity of the structural system,the lattice column support system is optimized.(4)By using the Midas/Gen finite element software containing the equivalent model of support system,the layer-by-layer construction process of the conversion truss is simulated.At the same time,the force of key components and the deflection deformation of key points in the steel trusses were also monitored in process of construction,so as to compare with the measured data obtained from the construction process test.The result of research demonstrated that the structural stress,deformation and deflection changes gently,measured values are less than the model values and the safety reserve is large,which meets the requirements of design in the process of layer-by-layer construction.