A beam ABCD rests on simple supports at B and C. The beam has a slight initial curvature so that end A is 15 mm above the elevation of the supports and end D is 10 mm above. What is the load Q (if P= 3200 N), acting at points A and D, respectively, will move points A and D downward to the level of the supports? (The flexural rigidity El of the beam is 2.5x 106 N-m².) B 10 mm 15 mm -2.5 m -2.5 m 2.5 m-

A beam ABCD rests on simple supports at B and C. The beam has a slight initial curvature so that end A is 15 mm above the elevation of the supports and end D is 10 mm above. What is the load Q (if P= 3200 N), acting at points A and D, respectively, will move points A and D downward to the level of the supports? (The flexural rigidity El of the beam is 2.5x 106 N-m².) B 10 mm 15 mm -2.5 m -2.5 m 2.5 m-

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter9: Deflections Of Beams

Section: Chapter Questions

Problem 9.5.26P: A beam A BCD rests on simple supports at B and C (see figure). The beam has a slight initial...

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A simply supported wooden I-beam with a 12-ft span supports a distributed load of intensity q = 90 lb/ft over its length (see figure part a). The beam is constructed with a web of Douglas-fir plywood and flanges of pine glued to the web, as shown in the figure part b. The plywood is 3/8 in. thick: the flanges are 2 in, × 2 in, (actual size). The modulus of elasticity for the plywood is 1,600,000 psi and for the pine is 1,200,000 psL Calculate the maximum bending stresses in the pine flanges and in the plywood web. What is q, if allowable stresses are 1600 psi in the flanges and 1200 psi in the web?
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