A composite beam is fabricated by bolting two 3.3-in.-wide by 13-in.-deep timber planks to the sides of a 0.5-in. by 13-in. steel plate. The moduli of elasticity of the timber and the steel are 1980 ksi and 30900 ksi, respectively. The simply supported beam spans a distance of 20 ft and carries two concentrated loads P, which are applied as shown. Assume LAB=LCD = 7 ft, LBc = 6 ft, b = 3.3 in., d = 13 in. and t = 0.5 in. (a) Determine the maximum bending stresses ,, produced in the timber planks and the steel plate if P = 3.9 kips. (b) Assume that the allowable bending stresses of the timber and the steel are 1040 psi and 27200 psi, respectively. Determine the largest acceptable magnitude for concentrated loads P. (You may neglect the weight of the beam in your calculations.) Answers: (a) o, = (b) P= i LAB i B * LBC Tr b b Cross section P kips. C LCD ksi, o, = i D ksi.

A composite beam is fabricated by bolting two 3.3-in.-wide by 13-in.-deep timber planks to the sides of a 0.5-in. by 13-in. steel plate. The moduli of elasticity of the timber and the steel are 1980 ksi and 30900 ksi, respectively. The simply supported beam spans a distance of 20 ft and carries two concentrated loads P, which are applied as shown. Assume LAB=LCD = 7 ft, LBc = 6 ft, b = 3.3 in., d = 13 in. and t = 0.5 in. (a) Determine the maximum bending stresses ,, produced in the timber planks and the steel plate if P = 3.9 kips. (b) Assume that the allowable bending stresses of the timber and the steel are 1040 psi and 27200 psi, respectively. Determine the largest acceptable magnitude for concentrated loads P. (You may neglect the weight of the beam in your calculations.) Answers: (a) o, = (b) P= i LAB i B * LBC Tr b b Cross section P kips. C LCD ksi, o, = i D ksi.

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter5: Stresses In Beams (basic Topics)

Section: Chapter Questions

Problem 5.7.2P: .2 A ligmio.irc ii supported by two vorlical beams consistins: of thin-walled, tapered circular...

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