Experimental Study On The Bearing Capacity Of Flexural Cold-formed Thin-Walled Channel Member With Web Holes

It is convenient for the structure side support and the installation of the circuit system and the piping installation.It is often used to open holes in the steel webs of cold bending thin-wall channels,and the opening of the web can reduce the flexural capacity of the components.Given the current domestic and foreign scholars on the web openings of cold-formed thin-walled steel components research mainly focused on compression member,this paper carried out web opening cold-formed thin-wall channel research of the bearing capacity of flexural member determine such component of the bending bearing capacity of the Direct Strength Method(Direct Strength Method,referred to as the DSM),for the future of engineering application and the cold bending thin-wall steel structure specification provide reference for further revision.Conducted a series of 16 Q345B web hole type cold bending thin-wall steel channel flexural member of static test,the research on the web has a different number of holes and edge width and different bending condition,the influence law of bearing capacity of specimen bending,there were no holes in holes,a hole,two and three holes,edge width is short side and long side,bending status to pure bending and pure bending.The experimental results show that the change of the number of holes in the web has little effect on the flexural capacity and buckling mode of the components.Edge width is an important factor affecting flexural capacity and buckling mode of component.Under the condition of the same section parameters,the flexural capacity of the component under pure bending is less than that of the non-pure bending state.There are four kinds of buckling modes in the experiment:distortional buckling,local buckling,distortion with distortion and local correlation buckling and local and distorted related buckling.Using finite element program ANSYS 12.0,the 16 experiments were simulated,and the geometrical and material nonlinearity was considered.The finite element simulation results show that the finite element analysis of buckling mode,flexural bearing capacity and bending moment-span vertical displacement curve is in good agreement with the experimental results.It is proved that the bearing capacity of flexural member is feasible,which provides a strong basis for the analysis of finite element parameters in the future.Web opening cold-formed thin-wall channel flexural member of solving the elastic buckling stress is about application of direct strength method in solving web opening cold-formed thin-wall channel flexural member application in solving the elastic distortional buckling stress reduction methods of cross section thickness reduction through thickness into finite elastic distortional buckling stress is obtained in the program,the calculation results compared with finite element program,and good agreement between the two.Solving web opebing cold-formed thin-wall channel flexural member elastic buckling stress,according to the existing research offers the formula method of solving,combined with the results of finite element analysis on the corresponding coefficient modification,given web opening cold-formed thin-wall channel flexural member of elastic buckling stress formula method.According to test results and finite element parametric analysis data,with the original members web as a benchmark,the design formula of direct strength method proposed is suitable for the web plate hole cold bending thin-wall channel design formula of flexural member of direct strength method.