Study On Shear Performance Of High Strength Cold-Formed Thin-Walled Steel Framing Walls With Cross-Bracing

The shear performance of high strength light steel dwelling walls being popularized and applied in our country is studied in this paper. The type of the wall studied in this paper is the wall cross-braced by the flat steel on both sides without wallboards, of which the steel strength is 550MPa. And the shear performance of the wall is studied by two methods, experimental research and nonlinear finite element analysis.Experimental research on the shear performance of two full-size high strength cold-formed thin-walled steel framing walls with cross-bracing, under monotonic loading without vertical compression loading and cyclic loading with vertical compression loading, is carried out in this paper. And the test set-up, the test phenomena, the data processing and the test results are described detailedly. Experimental results show that the failure of the wall specimens is due to the compression failure of the bottom track or the end stud; the shear resistance of wall specimens under monotonic loading is higher than that of wall specimens under cyclic loading; the shear strength of wall specimens, 60%～67% that of walls with double boards, is between 9.00kN/m and 10.01kN/m, which shows that the flat steel cross-bracing plays an important role in the shear performance of the walls with cross-bracing.The wall specimens under monotonic loading are simulated by the finite element program. And the material nonlinearity and the geometric nonlinearity are considered simultaneously in the finite element model, in which all members are simulated by the plastic shell element Shell 181, and the screw connections of all members are simulated by the coupling command. Moreover, the reasonable boundary conditions are established according to the test wall specimens for the loading and solution of the finite element model. And the finite element analysis results agree well with the experimental results, so the finite element model is validated. Based on the finite element model of the wall with cross-bracing, a detailed parameter analysis for five influencing factors of the shear resistance of the wall is carried out, including wall stud spacing, cross section of the wall stud, cross section of the cross-brace, setting flat steel cross-brace on one side, vertical loading and so on. And the finite element analysis results show that the wall stud spacing and the cross section of the cross-brace have little influence on the shear resistance of the wall; the shear resistance of the wall increases significantly with the increase of the cross section of the wall stud; the shear resistance of the wall decreases as the applied vertical load increases; the shear resistance of the wall setting flat steel cross-brace on one side is much lower than that of the wall setting flat steel cross-brace on both sides.