This paper presents the results of a study aiming at shape optimising singly-symmetric cold-formed steel purlins. The “self-shape” optimisation algorithm previously developed, proven to be robust and converge known solutions is used for this purpose. Eight cases are considered, consisting 1.5 mm 1.9 thick purlins, spanning either 3000 or 8000 drawn with 4, 6 8 elements per half cross-section. a...

This study proposes a design procedure for the local buckling strength prediction of cold-formed steel (CFS) built-up I and box section columns based on Effective Width Method (EWM) Direct Strength (DSM). For this, ultimate sections made two plain unlipped channels is obtained using finite element (FE) analysis. First, some compression tests are performed to validate FE models. Then, detailed p...

The objective of this paper is to explore the potential impact of the use of advanced high strength steel (AHSS) to form traditional cold-formed steel structural members. In this study, shell finite element models are constructed, and geometric and material nonlinear collapse analysis performed, on simulated lipped channel cross-section cold-formed steel members roll-formed from AHSS. AHSS shee...

Cold-formed structural sections are manufactured at ambient temperature and hence undergo plastic deformations which result in an increase in the yield stress and ultimate stress, but reduced ductility. This paper begins with a comparative study of existing predictive models to harness this strength increase. Modifications to the existing models are then made and an improved model is presented....

This paper describes the computations of micro-strains at inner corner of cold formed rectangular hollow sections (CFRHS) made up of structural steels using finite element analysis. In order to obtain the micro-strains, distortion test is simulated by modeling two-dimensional structural steel tubes in ANSYS software. Two dimensional linear static analyses are performed by defining elastic prope...

We observe the dynamic formation of quasibound Cs2 molecules near Feshbach resonances in a cold sample of atomic cesium. Using an external probe beam, more than 15 weakly coupled molecular states are detected with high sensitivity, whose collisional formation cross sections are as small as sigma=2 x 10(-16) cm(2). By modeling the molecule formation and dissociation processes with rate equations...

The strength of sheathed wall systems is substantially greater than unsheathed walls with the same studs. Testing on studs sheathed on both sides with dry gypsum board demonstrate strength increases as large as 70% over unsheathed studs (Miller and Peköz 1993, Miller and Peköz 1994). The current AISI Specification for sheathed wall stud systems are complicated, only apply when the sheathing is ...