Three 6.1 m span Pratt trusses with a 4:12 roof pitch and chords consisting of C-shapedlight gauge cold-formed steel stud sections were constructed and tested under four concentrated gravityloads approximating uniform snow loads. Gusset plates attached with self-tapping screws were used asconnections to allow all members to remain in plane making the trusses efficient in terms of storage andtransportation. Stiffeners were used to prevent local material failure at the load points while specimenswere simply supported and braced at the supports against lateral distortion approximating the effect ofsheathing on a typical roof detail. Specimen #1 failed by plate buckling at an end connection at anapproximate uniform load of 1.17 kN/m corresponding to point loads of 1.78 kN, while Specimen #2 failedat an approximate uniform load of 2.77 kN/m or 4.23 kN per point load. This specimen failed by bearing atan end connection. Specimen #3 failed by plate buckling at the peak connection at an approximateuniform load of 2.85 kN/m under concentrated loads of 4.34 kN. Adding lateral support and additionalstiffness to the end connections resulted in an overall capacity 2.4 times greater than in the case where nolateral support was provided.
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