Mechanics of Materials (MindTap Course List)
9th Edition
ISBN: 9781337093347
Author: Barry J. Goodno, James M. Gere
Publisher: Cengage Learning
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Textbook Question
Chapter 6, Problem 6.3.5P
A simple beam that is 18 ft long supports a uniform load of intensity q. The beam is constructed of two C8 x 11.5 sections (channel sections or C-shapes) on either side of a 4 × 8 (actual dimensions) wood beam (see the cross section shown in the figure part a). The modulus of elasticity of the steel (E; = 30,000 ksi) is 20 times that of the wood (Ew).
(a) If the allowable stresses in the steel and wood are 12,000 psi and 900 psi, respectively, what is the allowable load qmax Note: Disregard the weight of the beam, and see Table F-3(a) of Appendix F for the dimensions and properties of the C-shape beam.
(b) If the beam is rotated 90° to bend about its v axis (see figure part b) and uniform load q = 250 lb/ft is applied, find the maximum stresses trs and crw in the steel and wood, respectively Include the weight of the beam. (Assume weight densities of 35 lb/ft3 and 490 lb/ft3 for the wood and steel, respectively.)
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Maximum compressive stress (acompression) in orientation B
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is greater than orientation B by a factor of 2.
The figure below shows two solid homogenous rectangular beam sections with (breadth x depth)
dimensions in two different orientations as follows:
Beam Section Orientation A (t mm x 2t mm); and
Beam Section Orientation B (2t mm x t mm).
Both beams sag when subjected to the same loading and support conditions resulting in
compressive stresses above the centroid line (neutral axis).
Which statement accurately describes the relative maximum compressive stress (ocompression)
between these beam section orientations?
t mm
2t mm
2t mm
t mm
Beam Section Orientation A
Beam Section Orientation B
O a. Maximum compressive stress (ocompression) in orientation A is greater than orientation B
by a factor of 4.
O b. Maximum compressive stress (ocompression) in orientation B is greater than orientation A
by a factor of 2.
O c. Maximum compressive stress (ocompression) in orientation B is greater than orientation A
by a factor of 4.
O d. Maximum compressive stress (ocompression) in orientation A is…
The figure below shows two solid homogenous rectangular beam sections with (breadth x depth)
dimensions in two different orientations as follows:
Beam Section Orientation A (t mm x 2t mm); and
Beam Section Orientation B (2t mm x tmm).
Both beams sag when subjected to the same loading and support conditions resulting in
compressive stresses above the centroid line (neutral axis).
Which statement accurately describes the relative maximum compressive stress (ocompression)
between these beam section orientations?
O a.
O b.
Oc
tmm
2 mm
Beam Section Orientation A
2tmm
7 mm
Beam Section Orientation B
Maximum compressive stress (compression) in orientation B is greater than orientation A by
a factor of 2.
Maximum compressive stress (ocompression) in orientation A is greater than orientation B by
a factor of 4.
Maximum compressive stress (compression) in orientation B is greater than orientation A by
a factor of 4.
O d. Maximum compressive stress (ocompression) in orientation A is greater than…
Chapter 6 Solutions
Mechanics of Materials (MindTap Course List)
Ch. 6 - A composite beam is constructed using a steel...Ch. 6 - A wood beam is strengthened using two steel plates...Ch. 6 - A composite beam consisting of fiberglass faces...Ch. 6 - A wood beam with cross-sectional dimensions 200 mm...Ch. 6 - A hollow box beam is constructed with webs of...Ch. 6 - A r o lukI f/frm f «m t ub e of ou t sid e d ia...Ch. 6 - A beam with a guided support and 10-ft span...Ch. 6 - A plastic-lined steel pipe has the cross-sectional...Ch. 6 - The cross section of a sand wie h beam consisting...Ch. 6 - The cross section of a sandwich beam consisting of...
Ch. 6 - A bimetallic beam used in a temperature-control...Ch. 6 - A simply supported composite beam 3 m long carries...Ch. 6 - A simply supported wooden I-beam with a 12-ft span...Ch. 6 - -14 A simply supported composite beam with a 3.6 m...Ch. 6 - -15 A composite beam is constructed froma wood...Ch. 6 - A wood beam in a historic theater is reinforced...Ch. 6 - Repeat Problem 6.2-1 but now assume that the steel...Ch. 6 - Repeat Problem 6.2-17 but now use a...Ch. 6 - A sandwich beam having steel faces enclosing a...Ch. 6 - A wood beam 8 in. wide and 12 in. deep (nominal...Ch. 6 - A simple beam of span length 3.2 m carries a...Ch. 6 - A simple beam that is 18 ft long supports a...Ch. 6 - The composite beam shown in the figure is simply...Ch. 6 - The cross section of a beam made of thin strips of...Ch. 6 - Consider the preceding problem if the beam has...Ch. 6 - A simple beam thai is IS ft long supports a...Ch. 6 - The cross section of a composite beam made of...Ch. 6 - A beam is constructed of two angle sections, each...Ch. 6 - 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Solve the preceding problem using a W 310 x 129...Ch. 6 - A cantilever beam of W 12 × 14 section and length...Ch. 6 - A cantilever beam built up from two channel...Ch. 6 - A built-Lip I-section steel beam with channels...Ch. 6 - Repeat Problem 6.4-14 but use the configuration of...Ch. 6 - A beam with a channel section is subjected to a...Ch. 6 - A beam with a channel section is subjected to a...Ch. 6 - An angle section with equal legs is subjected to a...Ch. 6 - An angle section with equal legs is subjected to a...Ch. 6 - A beam made up all woun equal leg angles is...Ch. 6 - The Z-section of Example D-7 is subjected to M = 5...Ch. 6 - The cross section of a steel beam is constructed...Ch. 6 - The cross section of a steel beam is shown in the...Ch. 6 - A beam with a semicircular cross section of radius...Ch. 6 - .10 A built-up bourn supporting a condominium...Ch. 6 - Asteelpost (E = 30 × 106 psi) having thickness t =...Ch. 6 - A C 200 x 17.1 channel section has an angle with...Ch. 6 - A cold-formed steel section is made by folding a...Ch. 6 - 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