Analysis Of Recycled Concrete-filled Circular Steel Tube Columns Subjected To Comparession And Torsion

Concrete-filled steel tube is a member formed by pouring concrete inside a steel pipe.Compared with traditional ordinary concrete members,concrete-filled steel tubular members have many advantages such as:excellent seismic resistance,good plasticity,high toughness,high bearing capacity,high fire resistance and rapid construction.It is widely used in viaduct piers,high-rise buildings,power grid towers,and wind turbine supports.With the development of the construction industry and the advocacy of the green building industry,whether it is possible to use recycled concrete instead of virgin concrete as the in-fill material for steel pipes should be further studied.The cross-section of concrete-filled steel tubular columns is usually circular,rectangular or other cross-section.In this paper,the mechanical properties of circular-recycled concrete-filled steel tubular members under pure torsion and compression-torsion are studied.Studying the mechanical properties of circular steel tubular recycled concrete members under the condition of pure torsion and compression and torsion is an important basis for further study of the mechanical properties of similar members under complex stress conditions such as bending,bending and shearing.In this paper,the mechanical properties of the circular steel tube recycled concrete column under the conditions of pure torsion and compression and torsion are studied in depth from the aspects of experiment and finite element simulation analysis.The square steel tube is given on the basis of parameter analysis.The formula for calculating the torsional ultimate bearing capacity of recycled concrete and circular steel tube recycled concrete under pure torsion and compression and torsion.The specific work is as follows:1.Summarize the relevant research results at home and abroad,and determine the experimental scheme and theoretical analysis method of the mechanical properties of the circular steel tube recycled concrete members under pure torsion and compression and torsion.2.Four circular solid steel tube recycled concrete members and two circular empty steel tube recycled concrete members were designed to study the mechanical properties of the members under pure torsion condition.Based on the variation of axial compression ratio,six round solid steel tubular recycled concrete specimens were designed to study the mechanical properties of the components under compression and torsion,and the test data and results were further analyzed in detail.3.Using the finite element Abaqus CAE to calculate and extract the torque-rotation curve of the members in the pure torsion and compression-torsion conditions in this test,compare it with the test results,and find that the difference between the two is not large.Explain the correctness of the ABAQUS CAE calculation method adopted in this paper.Using the simulation analysis method,the working mechanism of typical components under different stress conditions of pure torsion and compression and torsion is analyzed.4.The main influencing factors of the torque-turn curve of the steel tube recycled concrete members under pure torsion and compression and torsion are analyzed in detail.On this basis,the correlation equation of the torsional bearing capacity of the steel tube recycled concrete members under the condition of pure torsion and compression and torsion is derived.Empirical calculation,the results obtained by this method are in good agreement with the finite element calculation results,and can be used as a reliable calculation method with reference value for engineering design.