| As cold-formed thin-wall steel structure housing gradually developed from lowlevel to high level, for the research on axial bearing capacity of sheathed cold-formedsteel studs is particularly necessary. While the research is only on cold-formed steelstuds without sheathing, not considering the influence of the sheathing, and lack ofpractical calculation method. So the axial bearing capacity of sheathed cold-formedsteel double-C studs is researched using finite element method, and a suggestedcalculation method of sheathed double-C studs is proposed.At first, sheathed cold-formed steel studs is modeled using nonlinear finite elementanalysis software ANSYS to simulate the test conducted by L.C.M. Vieira Jr., and theresults of finite element analysis and experimental results were compared both in goodagreement, so the reliability of the finite element model is verified. So we get a reliablefinite element model of sheathed cold-formed steel double-C studs.Secondly, the parametric research analysis was conducted to mainly determine theeffect of the height of double-C stud, the spacing of screw, sheathing thickness. Theresults of the study indicate that with the height of double-C stud and the spacing ofscrew increases, the axial bearing capacity of the sheathed double-C stud decreased. Thethickness of the gypsum board on the axial bearing capacity of sheathed double-C studhas little effect. When the thickness of the OSB board is less than9mm, it has asignificant effect on the axial bearing capacity of sheathed double-C stud.Finally, according to Timoshenko elastic theory, building a mechanical model ofsheathed double-C stud, the elastic buckling load of double-C stud without sheathed,double-C stud with one-side sheathed and double-C stud with two-sides sheathed isdeduced. According the deduced elastic buckling stress, modifying the calculation method of North American specification on the sheathed single-C stud to the sheatheddouble-C stud, then a suggested calculation method of the bearing capacity of sheatheddouble-C studs is proposed. Meanwhile based on the research of domestic and foreignscholars, we conducted an inelastic modification on our country’s specificationsregarding the carrying capacity of axial compression members calculation method, andthe calculation method is recommended to get the axial bearing capacity of sheatheddouble-C studs. Finally these two recommendations based on the finite element resultsare validated. |
