Mechanics of Materials (MindTap Course List)
9th Edition
ISBN: 9781337093347
Author: Barry J. Goodno, James M. Gere
Publisher: Cengage Learning
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Chapter 6, Problem 6.2.5P
A hollow box beam is constructed with webs of Douglas-fir plywood and flanges of pine, as shown in the figure in a cross-sectional view. The plywood is 1 in. thick and 12 in. wide; the flanges are 2 in. × 4 in. (nominal size). The modulus of elasticity for the plywood is 1,800,000 psi and for the pine is 1,400,000 psi.
- If the allowable stresses are 2000 psi for the plywood and 1750 psi for the pine, find the allowable bending moment Mmaxwhen the beam is bent about the z axis.
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A composite beam consists of concrete slab (1) that is rigidly attached to the top flange of a W16 × 40standard steel shape (2). The cross section of this composite beam is shown in Figure below. Concreteslab (1) has a width of b = 48 in., a thickness of t = 4 in., and an elastic modulus of 3,500 ksi. The elasticmodulus of the steel shape is 30,000 ksi, and the cross-sectional dimensions are presented below figure.For a bending moment of Mz = +150 kip·ft and , determine:(a) the location of the centroid for the transformed section, measured upward from point K.(b) the normal stress at H in the concrete slab.(c) the normal stress at K in the steel shape.
A steel beam, of lengths a = 5 m and b = 2 m and a hollow box cross section, is supported by a hinge support A and roller support B, see Figure Q.1. The width and height of the cross section are 200 mm and 300 mm, respectively, and the wall thickness of the cross section is 5 mm. The beam is under a distributed load of the intensity that linearly varies from q = 0 kN/m to q = 5 kN/m for AB span; and is constant with q = 5 kN/m for BC span. The Young’s modulus of steel is 200 GPa.
Questions:
1. Calculate the vertical support reaction in support A. When sketching FBD, set the positive directions of both reactions in the positive direction of y axis. Enter your answer in kN to three decimal places.
2. Calculate the vertical support reaction in support B. Enter your answer in kN to two decimal places.
3. Calculate the value of the maximum bending moment in the beam. Enter your answer in kNm to three decimal places.
Note: when deriving internal moment equations, use the following…
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 - The cross section of a bimetallic strip is shown...Ch. 6 - A W 12 x 50 steel wide-flange beam and a segment...Ch. 6 - A reinforced concrete beam (see figure) is acted...Ch. 6 - A reinforced concrete T-beam (see figure) is acted...Ch. 6 - A reinforced concrete slab (see figure) is...Ch. 6 - A wood beam reinforced using two channels is...Ch. 6 - A wood beam reinforced by an aluminum channel...Ch. 6 - A beam with a rectangular cross section supports...Ch. 6 - A wood beam with a rectangular cross section (see...Ch. 6 - Solve the preceding problem for the following...Ch. 6 - A simply supported wide-flange beam of span length...Ch. 6 - Solve the preceding problem using the fol...Ch. 6 - A wood cantilever beam with a rectangular cross...Ch. 6 - Solve the preceding problem for a cantilever beam...Ch. 6 - A 2-m-long cantilever beam is constructed using a...Ch. 6 - A wood beam AB with a rectangular cross section (4...Ch. 6 - A steel beam of I-section (see figure) is simply...Ch. 6 - A cantilever beam with a wide-flange cross section...Ch. 6 - 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 - A simple beam with a W 10 x 30 wide-flange cross...Ch. 6 - Solve the preceding problem for a W 250 × 44.8...Ch. 6 - A beam of wide-flange shape, W 8 x 28, has the...Ch. 6 - Solve the preceding problem for a W 200 × 41,7...Ch. 6 - Calculate the distance e from the cent crime of...Ch. 6 - Calculate the distance e from the centerline of...Ch. 6 - The cross section of an unbalanced wide-flange...Ch. 6 - The cross section of an unbalanced wide-flange...Ch. 6 - The cross section of a channel beam with double...Ch. 6 - The cross section of a slit circular tube of...Ch. 6 - The cross section of a slit square tube of...Ch. 6 - The cross section of a slit rectangular tube of...Ch. 6 - A U-shaped cross section of constant thickness is...Ch. 6 - Derive the following formula for the distance e...Ch. 6 - Derive the following formula for the distance e...Ch. 6 - The cross section of a sign post of constant...Ch. 6 - A cross section in the shape of a circular arc of...Ch. 6 - Determine the shape factor f for a cross section...Ch. 6 - (a) Determine the shape factor/for a hollow...Ch. 6 - A propped cantilever beam of length L = 54 in....Ch. 6 - A steel beam of rectangular cross section is 40 mm...Ch. 6 - .5 Calculate the shape factor j for the...Ch. 6 - Solve the preceding problem for a wide-flange beam...Ch. 6 - Determine the plastic modulus Z and shape...Ch. 6 - Prob. 6.10.8PCh. 6 - Prob. 6.10.9PCh. 6 - Prob. 6.10.10PCh. 6 - A hollow box beam with height h = 16 in,, width h...Ch. 6 - Solve the preceding problem for a box beam with...Ch. 6 - A hollow box beam with height h = 9.5 in., inside...Ch. 6 - Solve the preceding problem for a box beam with...Ch. 6 - The hollow box beam shown in the figure is...Ch. 6 - Prob. 6.10.16PCh. 6 - Prob. 6.10.17PCh. 6 - A singly symmetric beam with a T-section (see...Ch. 6 - A wide-flange beam with an unbalanced cross...Ch. 6 - .20 Determine the plastic moment Mpfor beam having...
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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?arrow_forwardTwo wood beams, each of rectangular cross section (3.0 in. x 4.0 in., actual dimensions), are glued together to form a solid beam with dimensions 6.0 in. x 4.0 in. (sec figure). The beam is simply supported with a span of S ft. What is the maximum moment Mmaxthat may be applied at the left support if the allowable shear stress in the glued joint is 200 psi? (Include the effects of the beams own weight, assuming that the wood weighs 35 lb/ft3.) Repeat part (a) if Mmaxis based on allowable bending stress of 2500 psi.arrow_forward-14 A simply supported composite beam with a 3.6 m span supports a triangularly distributed load of peak intensity q0at mid-span (see figure part a). The beam is constructed of two wood joists, each 50 mm x 280 mm, fastened to two steel plates, one of dimensions 6 mm × 80 mm and the lower plate of dimensions 6 mm x 120mm (see figure part b). The modulus of elasticity for the wood is 11 GPa and for the steel is 210 GPa. If the allowable stresses are 7 MPa for the wood and 120 MPa for the steel, find the allowable peak load intensity q0maxwhen the beam is bent about the z axis. Neglect the weight of the beam.arrow_forward
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