Experimental study on uplift capacity of purlins considering restraints from standing seam roof systems

摘要

A total of 32 specimens of single-span purlin roof assemblies considering uplift wind load were tested to investigate the structural behavior of cold-formed steel purlins with one flange fastened to standing seam roofs. Failure modes and failure loads of purlins with different parameters were obtained. Full finite element models, incorporate purlins, clips and standing seam roof panels, were developed, and the analysis results were consistent to a high degree with the test results. Using the same element type and material model, the rotational restraint of test roof systems and corresponding influence factors were investigated by finite element models. Finally, using the rotational restraint rigidities and comparing with the test results, the lateral restraint of test roof systems were also studied through a simple finite element model incorporates pure the purlin and presents the rotational restraints and lateral restraints by rotational and lateral springs. It is shown that the standing seam roofs do provide some extent of rotational restraints and lateral restraints to purlins at the connection points, especially for purlins without sag rod.