| Self-drilling screws are the primary means of fastening cold-formed steel members in residential construction. A better understanding of the behavior of screw connection could lead to more optimum connection design. The study's focus is describing the detailed results on bearing capacity of self-drilling screws connection by tests and numerical analysis. A more proper method is recommended.At first, the bearing capacities of single self-drilling screw connection and self-drilling screws connection have been tested. The detail of test device, experiment method, destructive process and test result are described elaborately in this paper. The destructive mechanism of self-drilling screws connection is recorded in the test. A result showed in experiment, when the number of self-drilling screws n≥2, there will be "Group Effect"-bearing capacity can not increase in the same ratio.After that, nonlinear finite element analysis involving geometric large deformation, materials nonlinear and contact problem is used to simulate test models in this paper. Members are modeled as solid elements, then plates and screws are glued. The equation resolution method is selected by ANSYS program automatically. From the comparison of computer analysis with experimental results, the finite element model is more accurate. The parametric study analysis was carried out to mainly determine the effect of the diameter and the number of screws, fastener patterens and screw spacing. The results of the study indicate that the diameter of screw is a major factor to bearing capacity of single self-drilling screw connection. The number of screws and screw spacing are main factors to bearing capacity of self-drilling screws connection, and the fastener patterens can be ignored.Finally, based on the test and the nonlinear finite element analysis, the design rule and the simple corresponding design method are proposed. Compared with the ANSYS and the test results, the proposed method indicates high degree of accuracy.
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