Criteria for Connection Spacing in Cold‐Formed Steel

Based on the elastic plate buckling theory, the development of criteria for maximum connection spacing in cold‐formed steel cellular panels subjected to gravity loading is presented. In such thin‐walled members, the maximum allowable spacing is governed either by the strength of the connection, or by local buckling of component compression plates. The determination of connection spacing can be based solely on the connection strength criterion when the connected elements are subjected to in‐plane tensile stresses. However, when the component parts are in compression, it becomes necessary to constrain the separation of compressed plates along the lines of connections so as to preserve fully composite action. The spacing criterion developed here for preventing the separation of the cover plate from the fluted sheet of the panel ensures the continuous stiffening effect along each line of connections. The requirement regarding unstiffened flanges is determined by assuming a slight amount of rotational restraint along its supported edge. In addition, the current connection design provisions adopted by the American Iron and Steel Institute (AISI) are reviewed. The AISI provisions and the proposed requirements are compared with the available experimental data, and a sample problem is solved in an appendix.