A beam with a guided support and 10 t span supports a distributed load of intensity a630 Ib/t over its first haf (see figure part (a)) and a moment M, 313t at joint a. 0.25 in. Mo II.5 in. 025 in. (a) 5.5 in. (b) The beam consists of a wood member (nominal dimensions 6 in. x 12 in. and actual dimensions 5.5 in. x11.5 in. in cross section, as shown in the figure part (b)) that is reinforced by 0.25-in.-thick steel plates on top and bottom. The moduli of elasticity for the steel and wood are E, 30 x 10 psi and E1.5 x 10 psi, respectively. (Assume that the component parts of the beams are securely bonded by adhesives or connected by fasteners. Also, be sure to use the general theory for composite beams described in the textbook.) (a) Calculate the maximum bending stresses a, in the steel plates and a in the wood member due to the applied loads. (Enter the magnitudes in pai.) psi psi (b) If the allowable bending stress in the steel plates is o 14,000 psi and that in the wood is 900 psi, find (Enter your answer in bft. Assume that the moment at 8, Ma, remains at 313 Ib-ft.) (s) Ifg 630 Ib/t and allowable stress values in part (b) apply, what is M. at 87 (Enter the magnitude in Ib-ft.) Ib-ft

A beam with a guided support and 10 t span supports a distributed load of intensity a630 Ib/t over its first haf (see figure part (a)) and a moment M, 313t at joint a. 0.25 in. Mo II.5 in. 025 in. (a) 5.5 in. (b) The beam consists of a wood member (nominal dimensions 6 in. x 12 in. and actual dimensions 5.5 in. x11.5 in. in cross section, as shown in the figure part (b)) that is reinforced by 0.25-in.-thick steel plates on top and bottom. The moduli of elasticity for the steel and wood are E, 30 x 10 psi and E1.5 x 10 psi, respectively. (Assume that the component parts of the beams are securely bonded by adhesives or connected by fasteners. Also, be sure to use the general theory for composite beams described in the textbook.) (a) Calculate the maximum bending stresses a, in the steel plates and a in the wood member due to the applied loads. (Enter the magnitudes in pai.) psi psi (b) If the allowable bending stress in the steel plates is o 14,000 psi and that in the wood is 900 psi, find (Enter your answer in bft. Assume that the moment at 8, Ma, remains at 313 Ib-ft.) (s) Ifg 630 Ib/t and allowable stress values in part (b) apply, what is M. at 87 (Enter the magnitude in Ib-ft.) Ib-ft

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter6: Stresses In Beams (advanced Topics)

Section: Chapter Questions

Problem 6.2.7P: A beam with a guided support and 10-ft span supports a distributed load of intensity q = 660 lb/ft...

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A beam with a guided support and 10-ft span supports a distributed load of intensity q = 660 lb/ft over its first half (see figure part a) and a moment Mq = 300 ft-lb at joint B. The beam consists of a wood member (nominal dimensions 6 in. x 12 in. and actual dimensions 5.5 in. x 11.5 in. in cross section, as shown in the figure part b) that is reinforced by 0.25-in.-thick steel plates on top and bottom. The moduli of elasticity for the steel and wood are £s = 30 X 106 psi and £"w = 1.5 X 106 psi, respectively. Calculate the maximum bending stresses trs in the steel plates and rw in the wood member due to the applied loads. If the allowable bending stress in the steel plates is = 14,000 psi and that in the wood is (T.dV!= 900 psi, find qmiiX. (Assume that the moment at .fi, A/0, remains at 300 ft-lb.) If q = 660 lb/ft and allowable stress values in part (b) apply, what is Müm^ at B?