Research On Flexural Properties Of Cold-formed Thin-walled Steel And Wood Plastic Composite Beam

The policy of our country vigorously promotes the assembly building,but the cold-formed thin-walled steel beam of its component is easy to have the flexural capacity,bending stiffness and ductility defect caused by local buckling.Therefore,the paper studies the measures to improve the bending resistance of cold-formed thin-walled steel beams,and develops a cold-formed thin-walled steel wood plastic composite beam.In order to discuss the bending resistance of the composite beam,the bending test and ANSYS numerical simulation of the cold-formed thin-walled steel beams,wood plastic beam and composite beam are carried out in this paper,and the flexural capacity,bending stiffness and ductility of the three are compared and analyzed,and the design method suitable for the cold-formed thin-walled steel and wood plastic composite beams is put forward.The main research work of this paper are as follows:(1)In view of the cold-formed thin-walled steel and wood plastic composite beam,the simplified formula of bending bearing capacity and bending stiffness is deduced based on the assumption of flat section,and the design method of it is put forward too.(2)3 wood plastic beams,5 cold-formed thin-walled steel beams and 5cold-formed thin-walled steel and wood plastic composite beams were designed and made.Through bending test,the flexural capacity and bending stiffness of wood plastic beam,steel beam and composite beam are compared and analyzed.It is concluded that composite beams have higher flexural capacity,flexural rigidity and other flexural properties than steel beams and wood plastic beams.(3)Based on the experimental results,the numerical simulation of the cold-formed thin-walled steel wood plastic composite beam and the cold-formed thin-walled steel beam is carried out.It is further verified that the composite beams have higher bending bearing capacity and bending stiffness,The influence of height width ratio,width thickness ratio(width of composite beam / steel thickness of composite beam)on flexural performance of composite beams is emphatically analyzed.It is concluded that increasing the ratio of height to width of composite beams or reducing the width to thickness ratio of composite beams can improve the flexural capacity,flexural rigidity and ductility of compositebeams.Finally,the correctness of the simplified formula of bending bearing capacity and bending stiffness is verified by comparing the results of numerical simulation with the experimental results and the calculated results.