Question

The truss shown in the figure below is one of several roof trusses spaced 15.0* at 20 feet apart. Purlins are located at the joints. The weight of the roofing material is 5 psf, and the snow load is 15 psf of horizontal projection of the roof surface. The self-weight of the truss (including purlins) is estimated to be 10 psf of horizontal projection of the roof surface. Use LRFD and design the lightest square HSS for the most critical top chord members of the truss using all mandatory and recommended criteria. 6@15'0" -90-0"

Answer 1

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= 0.4038 kips.fr 333 kipS ompute he bendng MDet about x-anis as Polloss Sulestitute ft lard 0-3931 kips A n dun out 5 bea usin he given fsmo

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ende Mas Compact Sec on iS e the vaJuS steal is E Subst q.152

E -O 24-03 astic r len foy the section as 2- схе anis is z and he yiels staeglh is Substitu so fsi Mon

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