Experimental Study On Axial Compression Behavior Of Fabricated GFRP Pipe Steel Fiber Tailings Reinforced Concrete Columns

With the promotion of prefabricated building technology in China,the research of new type of fabricated concrete composite columns has high application value and broad promotion prospects.China's tailings resources are abundant,and high-performance concrete can be prepared from tailings.The most suitable GFRP material has good mechanical properties and corrosion resistance.The combined column of GFRP pipe and high-performance tailings concrete has certain Research significance.Combining the combined column with fabricated building technology will have good promotional value.GFRP pipe concrete composite column has many advantages in terms of force,construction process and internal concrete protection from erosion due to its structural form,and has irreplaceable application prospects.In order to effectively promote the application of GFRP pipe concrete composite columns,a lot of work needs to be done.Therefore,it is particularly important to further study the stress characteristics of GFRP pipe concrete columns,the vertical connection between columns and the assembly joints between beams and columns.This paper focuses on the experimental study of the mechanical performance of GFRP pipe concrete composite columns,and specifically carried out the following aspects:(1)The GFRP tube was tested for material properties as the basis for the study of GFRP pipe concrete composite columns.The concrete materials used in the test were tested and the high-performance steel fiber tailings concrete was arranged as the concrete used for the test pieces.(2)The axial compression experiments were carried out on the composite column and the two combined splicing columns.Some factors affecting the mechanical performance of the composite column were studied,including the concrete type,the thickness of the GFRP wall and the splicing form of the GFRP tube.The experimental results show that the bearing capacity of the composite column will increase obviously with the thickening of the pipe wall.A splicing joint of the steel pipe joint form and another GFRP pipe splicing form is proposed.The splicing form of the two GFRP pipes has no combined column.The bearing capacity and the deforming ability cause loss and achieve the application effect;although the steel fiber concrete does not increase the ultimate bearing capacity of the combined column,it will effectively improve the early resistance of the combined column.(3)The theoretical analysis and bearing capacity calculation of the ultimate bearing capacity of GFRP pipe concrete composite columns are carried out.The force mechanism of GFRP pipe,confined concrete and composite column in combined column is studied.The calculation results and test results are obtained by deriving formula.In contrast,the two are relatively close,which can provide a certain reference for the application of the combined column.(4)The design of GFRP pipe concrete composite column beam-column joints is studied,and a reliable assembled beam-column joint node is proposed,which provides a powerful guarantee for the application of composite column.(5)The prefabrication process of the combined column and the splicing and installation process of the beam and column were studied,which played a guiding role in the fabrication and construction of the combined column.(6)The economic performance analysis of the combined injection is carried out.The GFRP pipe concrete composite column has obvious advantages over the traditional reinforced concrete column.