Study On Mechanical Properties Of The Concrete Filled Circular Frp-steel Composite Tube Column

The concrete filled FRP-steel composite tube is a new composite structure thatpasted longitudinal and transverse composite fiber material in steel tube lateral toform a composite tube, and filled concrete internally, so that the core concrete insidethe steel tube is under the double constraint of FRP and steel tube, it can improve thebearing capacity of concrete filled steel tube.In this paper, there are complementary studies on the basis of existing research.First of all,the construction process of the concrete filled FRP-steel composite tubestructure were proposed;Then, the mechanical properties of the concrete filledcircular FRP-steel composite tube stub columns were studied under axiallycompressed monotonous,and the large finite element software ABAQUS was used tosimulate the axially compressed concrete filled FRP-steel composite tube component,and comparing the result of test and simulation; Finally, the test results were used toengineering practice.Through the above research, the following main conclusionscan be drawn:(1) The construction process of the concrete filled FRP-steel composite tubestructure including processing steel tube→pouring concrete→polishing steel tubeouter→pasting FRP→brushing the special coating of fiber composite material.(2) When the concrete filled circular FRP-steel composite tube stub columnsunder monotonic axially compressed load, whether it is CFRP or BFRP,or bothmixed,the ultimate bearing capacity increased in varying degrees as the layers ofFRP layers increased;the improved effect of CFRP was better than BFRP under thesame number of FRP layers. With the experimental data, the simplify calculationformula of the bearing capacity of the concrete filled circular FRP-steel compositetube columns was derived, it showed good agreement with experiment andcalculation. By the finite element software to simulate the axially compressedconcrete filled FRP-steel composite tube stub columns also showed the simulatedcurves and the experimental curves were in good agreement.(3) The concrete filled FRP-steel composite tube structure was applied to theactual pier according to the research results; the design and construction of theconcrete filled FRP-steel composite tube pier were more in-depth studied and theconstruction techniques and critical process were also proposed.