Concept explainers
Solve Prob. 5.94, assuming that the 6-kN concentrated load P applied to each beam is replaced by 3-kN concentrated loads P1 and P2 applied at a distance of 4 m from each end of the beams.
5.94 A roof structure consists of plywood and roofing material supported by several timber beams of length L = 16 m. The dead load carried by each beam, including the estimated weight of the beam, can be represented by a uniformly distributed load wD = 350 N/m. The live load consists of a snow load, represented by a uniformly distributed load wL = 600 N/m, and a 6-kN concentrated load P applied at the midpoint C of each beam. Knowing that the ultimate strength for the timber used is σU = 50 MPa and that the width of the beam is b = 75 mm, determine the minimum allowable depth h of the beams, using LRFD with the load factors γD = 1.2, γL = 1.6 and the resistance factor ϕ = 0.9.
Fig. P5.94
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- International Edition---engineering Mechanics: St...Mechanical EngineeringISBN:9781305501607Author:Andrew Pytel And Jaan KiusalaasPublisher:CENGAGE L