The pin-connected structure shown in the figure consists of a rigid beam ABCD and two supporting bars. Bar (1) is a bronze alloy [E = 101 GPa] with a cross-sectional area of A₁ - 230 mm². Bar (2) is an aluminum alloy [E = 71 GPa] with a cross-sectional area of A₂ - 740 mm². All bars are unstressed before the load P is applied; however, there is a 4-mm clearance in the pin connection at A. Assume L₁ = 2040 mm, a = 1020 mm, b = 630 mm, c = 460 mm, and L₂=1470 mm. If a load of P = 155 kN is applied at B, determine (a) the normal stresses in both bars (1) and (2). (b) the downward deflection of point A on the rigid bar. (1) L a b Answers: (a) 0₁ - 02₂- (b) VA- i MPa MPa mm 2 L2

The pin-connected structure shown in the figure consists of a rigid beam ABCD and two supporting bars. Bar (1) is a bronze alloy [E = 101 GPa] with a cross-sectional area of A₁ - 230 mm². Bar (2) is an aluminum alloy [E = 71 GPa] with a cross-sectional area of A₂ - 740 mm². All bars are unstressed before the load P is applied; however, there is a 4-mm clearance in the pin connection at A. Assume L₁ = 2040 mm, a = 1020 mm, b = 630 mm, c = 460 mm, and L₂=1470 mm. If a load of P = 155 kN is applied at B, determine (a) the normal stresses in both bars (1) and (2). (b) the downward deflection of point A on the rigid bar. (1) L a b Answers: (a) 0₁ - 02₂- (b) VA- i MPa MPa mm 2 L2

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter2: Axially Loaded Members

Section: Chapter Questions

Problem 2.7.7P: -7 The truss A BC Shawn in the figure supports a horizontal load P1= 300 lb and a vertical load P2=...

See similar textbooks

Similar questions

A rigid bar of weight W = 750 lb hangs from three equally spaced wires: two of steel and one of aluminum (see figure). The diameter of the wires is 1/8 in. Before they were loaded, all three wires had the same length. What temperature increase T in all three wires will result in the entire load being carried by the steel wires? (Assume Es= 30 × 106 psi, as= 6.5 × 10-6 /'F, and aa= 12 × 10-6F.)
An L-shaped reinforced concrete slab 12 Ft X 12 ft, with a 6 Ft X 6 ft cut-out and thickness t = 9.0 in, is lifted by three cables attached at O, B, and D, as shown in the figure. The cables are are combined at point Q, which is 7.0 Ft above the top of the slab and directly above the center of mass at C. Each cable has an effective cross-sectional area of Ae= 0.12 in2. (a) Find the tensile force Tr(i = 1, 2, 3) in each cable due to the weight W of the concrete slab (ignore weight of cables). (b) Find the average stress ov in each cable. (See Table I-1 in Appendix I for the weight density of reinforced concrete.) (c) Add cable AQ so that OQA is one continuous cable, with each segment having Force T, which is connected to cables BQ and DQ at point Q. Repeat parts (a) and (b). Hini: There are now three Forced equilibrium equations and one constrain equation, T1= T4.
Wires B and C are attached to a support at the left-hand end and to a pin-supported rigid bar at the right-hand end (see figure). Each wire has cross-sectional area A =0.03 in2 and modulus of elasticity E = 30 X 106 psi. When the bar is in a vertical position, the length of each wire is L = 80 in. However, before being attached to the bar, the length of wire B was 79.98 in. and wire C was 79.95 in. Find the tensile forces TBand Tc in the wires under the action of a force P = 700 lb acting at the upper end of the bar.
The structure shown in the figure consists of a horizontal rigid bar ABCD supported by two steel wires: one of length L and the other of length 3L/4. Both wires have cross-sectional area A and are made of elastoplastic material with yield stress aYand modulus of elasticity E. A vertical load P acts at end D of the bar. (a) Determine the yield load PYand the corresponding yield displacement grat point D. (b) Determine the plastic load Ppand the corresponding displacement
A hollow circular tube T of a length L = 15 in. is uniformly compressed by a force P acting through a rigid plate (see figure). The outside and inside diameters of the tube are 3.0 and 2.75 in., respectively. A concentric solid circular bar B of 1.5 in. diameter is mounted inside the lube. When no load is present, there is a clearance c = 0.0I0 in. between the bar B and the rigid plate. Both bar and tube are made of steel having an c[autoplastic stress-strain diagram with E = 29 X LO3 ksi and err= 36 ksi. (a) Determine the yield load Pt- and the corresponding shortening 3yof the lube. (b) Determine the plastic load Ppand the corresponding shortening Spof the tube. (c) Construct a load-displacement diagram showing the load Pas ordinate and the shortening 5 of the tube as abscissa. Hint: The load-displacement diagram is not a single straight line in the region 0 ^ P ^ Pr
A compressive load P is transmitted through a rigid plate to three magnesium-alloy bars that are identical except that initially the middle bar is slightly shorter than the other bars (see figure). The dimensions and properties of the assembly are as follows: length L = 1.0 m, cross-sectional area of each bar A = 3000 mm", modulus of elasticity E = AS GPa, and the gap s = 1.0 mm. (a) Calculate the load Ptrequired to close the gap. (b) Calculate the downward displacement 5 of the rigid plate when P = 400 kN. (c) Calculate the total strain energy V of the three bars when P = 400 kN (d) Explain why the strain -energy V is not equal to PS/2. Hint: Draw a load-displacement diagram.
A column ABC is supported at ends A and C and compressed by an axial load P (figure a). Lateral support is provided at point B but only in the plane of the figure; lateral support perpendicular to the plane of the figure is provided only at A and C. The column is constructed of two channel sections (C 6 × 8.2) back to back (see figure b). The modulus of elasticity of the column is E = 29,500 ksi and the proportional limit is 50 ksi. The height of the column is L = 15 ft. Find the allowable value of load P using a factor of safety of 2.5.
A trimetallic bar is uniformly compressed by an axial force P = 9 kips applied through a rigid end plate (see figure}. The bar consists of a circular steel core surrounded by brass and copper tubes. The steel core has a diameter of L.25 i n., the brass tube has an outer diameter of 1.75 in., and the copper tube has an outer diameter of 2.25 in. The corresponding modulus of elasticity are f, = 30, 000 ksi, Eb= 16,000 ksi, and E = 18,000 ksi Calculate the compressive stresses ers, ab, and cin the steel, brass, and copper, respectively, due to the force P.
Three prismatic bars, two of material A and one of material B. transmit a tensile load P (see figure). The two outer bars (material A) are identical. The cross-sectional area of the middle bar (material B) is 50% larger than the cross-sectional area of one of the outer bars. Also, the modulus of elasticity of material A is twice that of material B. (a) What fraction of the load P is transmitted by the middle bar? (b) What is the ratio of the stress in the middle bar to the stress in the outer bars? (c) What is the ratio of the strain in the middle bar to the strain in the outer bars?
A plastic rod AB of length L = 0.5 m has a diameter d1= 30 mm (see figure). A plastic sleeve CD of length c = 0.3 m and outer diameter d2= 45 mm is securely bonded to the rod so that no slippage can occur between the rod and the sleeve. The rod is made of an acrylic with a modulus of elasticity E1= 3.1 GPa, and the sleeve is made of a polyamide with E2= 2.5 GPa. (a) Calculate the elongation d of the rod when it is pulled by axial forces P = 12 kN. (b) If the sleeve is extended for the full length of the rod, what is the elongation? (c) If the sleeve is removed, what is the elongation?
Two pipe columns (AB, FC) are pin-connected to a rigid beam (BCD), as shown in the figure. Each pipe column has a modulus of E, but heights (L1or L2) and outer diameters (d1or different for each column. Assume the inner diameter of each column is 3/4 of outer diameter. Uniformly distributed downward load q = 2PIL is applied over a distance of 3L/4 along BC, and concentrated load PIA is applied downward at D. (a) Derive a formula for the displacement
Around brass bar of a diameter d1= 20mm has upset ends each with a diameter d2= 26 mm (see figure). The lengths of the segments of the bar are L1= 0.3 m and L2= 0.1 m. Quarter-circular fillets are used at the shoulders of the bar, and the modulus of elasticity of the brass is E = 100 GPa. If the bar lengthens by 0.12 mm under a tensile load P, what is the maximum stress ??maxin the bar?