Nonlinear Analysis of Cold-Formed Steel Shear Diaphragms

The method is based on residual forces. Diaphragms are modeled by finite elements of three types: (1)The individual panel units; (2)the supporting steel framing; and (3)the connectors. The connectors are considered to be the sole source of nonlinear behavior, essentially as indicated by experimental evidence. The computer program is user-oriented, and is equipped with an automatic mesh generator as well as an accelerator to improve convergence rate. Applications of the analysis to diaphragms for which full-scale test results are available show good correlation. The method provides full information on displacements and internal force distributions, as well as overall behavior, and thus provides a sound basis for the development of approximate methods suitable for manual design. It may be directly useful for the design of complex systems such as those including large openings or having unusual proportions, or for the design of innovative stressed-skin structures such as folded plates.