QUESTION 1 (10 marks) 20 kN 60 kN B C D 2 m 6 m 2...

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QUESTION 1 (10 marks) 20 kN 60 kN B C D 2 m 6 m 2 m The simply supported beam shown above has two point loads, at the two locations A and C shown above. a. Find reactions at B and D, and then NEATLY draw the shear force and bending moment diagrams. Don't forget to label the axes and show all values. (7) b. What is the maximum bending stresses with a W410x60 profile? Compare the factor of safety using aluminum alloy 2014-T4 to structural steel ASTM-A36. (3) Units: KN-m QUESTION 2 (10 marks) 40 kN 35 kN/m 40 kN 60 kN/m A B C D 2.4 m 3.0 m 4.6 m 40.0 kN 40.0 kN 60.0 kN/m 35.0 kN/m Units: KN 2.4 m 3 m 4.6 m 315.59 kN 191.59 -40.00 -124.00 86.59 46.59 @x-6.18 m 238.57 2.0 m 2 m 389.41 kN 160.00 -229.41 40 kN E 40.0 kN 40.00 A loading has been analyzed, with reactions, shear force, and bending moments as shown to the left. a. What is the minimum required section modulus for a material that has an allowable yield strength of 200 MPa? What is this modulus if yield strength is only 150 MPa? (3) b. Select the most economical W530, W460, and W410wide flange sections from the table in the textbook, for each of the three materials. (3) c. Confirm the sections chosen by checking the maximum stress values in the sections that you have chosen. (3) d. If a hole needs to be drilled to hang a lightweight attachment ( <10 N), what is the best location along the beam length? (1) -196.80 220.48 -200.00 QUESTION 3 (10 marks) 1.5 kN 2.5 kN -200 200 -100- 50 50 10 -10 d=30- d=40 - d = 60 - d = 50 d = 40 2.2 kN 1.8 kN I Part geometry has a significant effect upon the overall safety of components. The part shown is machined from 6061-T6 and all dimensions shown are in mm, with all fillet radii being 2 mm. Reactions are already solved, shown above. a. Neatly draw the shear force and bending moment diagrams. (7) b. Determine the Factor of Safety for the machine part. What is the Factor of Safety if the component is machined from 2014-T6? (3 marks) QUESTION 4 (5+5=10 marks) The steel shaft of a socket wrench has an allowable shear stress of 60 MPa. (G=78 GPa) a. What is the maximum permissible torque that can be exerted, and how many degrees does the wrench turn? b. What is the maximum permissible torque if the rotation is limited to 3 degrees? What is the actual stress and factor of safety with this 3 degree rotation? d = 8.0 mm - L = 200 mm T QUESTION 4 (continued) A tubular steel shaft is being designed to transmit 225 kW at 1700 RPM, with maximum shear stress limited to not more than 30 MPa. If the outside diameter of the shaft is 75 mm, what is the minimum wall thickness for the shaft? QUESTION 5 (5+5 = 10 marks) P8.90 The grooved shaft shown in Figure P8.90 is made of C86100 bronze (see Appendix D for properties). The major shaft diameter is D = 50 mm, the minor shaft diameter at the groove is d = 34 mm, and the radius of the groove is = 4 mm. Determine the maximum allowable moment M that may be applied to the shaft if a factor of safety of 1.5 with respect to failure by yield is specified. M D FIGURE P8.90 Radius r M QUESTION 5 (continued) A cylindrical boiler with an OD of 2.8-m and a wall thickness of t=33 mm was fabricated from an alloy with yield stress of 335 MPa. Determine the maximum hoop stress produced by an internal pressure of 2.3 MPa. What is the maximum internal pressure if a factor of safety of 3 is required? QUESTION 6 (5+5=10 marks) A R L b B Problem 5.5-6 A freight-car axle AB is loaded approximately as shown in the figure, with the forces P representing the car loads (transmitted to the axle through the axle boxes) and the forces R representing the rail loads (transmitted to the axle through the wheels). The diameter of the axle is d = 80 mm, the distance between centers of the rails is L, and the distance between the forces P and is R is b = 200 mm. Calculate the maximum bending stress max in the axle if P = 47 kN. QUESTION 1 (10 marks) 20 kN 60 kN B C D 2 m 6 m 2 m The simply supported beam shown above has two point loads, at the two locations A and C shown above. a. Find reactions at B and D, and then NEATLY draw the shear force and bending moment diagrams. Don't forget to label the axes and show all values. (7) b. What is the maximum bending stresses with a W410x60 profile? Compare the factor of safety using aluminum alloy 2014-T4 to structural steel ASTM-A36. (3) Units: KN-m QUESTION 2 (10 marks) 40 kN 35 kN/m 40 kN 60 kN/m A B C D 2.4 m 3.0 m 4.6 m 40.0 kN 40.0 kN 60.0 kN/m 35.0 kN/m Units: KN 2.4 m 3 m 4.6 m 315.59 kN 191.59 -40.00 -124.00 86.59 46.59 @x-6.18 m 238.57 2.0 m 2 m 389.41 kN 160.00 -229.41 40 kN E 40.0 kN 40.00 A loading has been analyzed, with reactions, shear force, and bending moments as shown to the left. a. What is the minimum required section modulus for a material that has an allowable yield strength of 200 MPa? What is this modulus if yield strength is only 150 MPa? (3) b. Select the most economical W530, W460, and W410wide flange sections from the table in the textbook, for each of the three materials. (3) c. Confirm the sections chosen by checking the maximum stress values in the sections that you have chosen. (3) d. If a hole needs to be drilled to hang a lightweight attachment ( <10 N), what is the best location along the beam length? (1) -196.80 220.48 -200.00 QUESTION 3 (10 marks) 1.5 kN 2.5 kN -200 200 -100- 50 50 10 -10 d=30- d=40 - d = 60 - d = 50 d = 40 2.2 kN 1.8 kN I Part geometry has a significant effect upon the overall safety of components. The part shown is machined from 6061-T6 and all dimensions shown are in mm, with all fillet radii being 2 mm. Reactions are already solved, shown above. a. Neatly draw the shear force and bending moment diagrams. (7) b. Determine the Factor of Safety for the machine part. What is the Factor of Safety if the component is machined from 2014-T6? (3 marks) QUESTION 4 (5+5=10 marks) The steel shaft of a socket wrench has an allowable shear stress of 60 MPa. (G=78 GPa) a. What is the maximum permissible torque that can be exerted, and how many degrees does the wrench turn? b. What is the maximum permissible torque if the rotation is limited to 3 degrees? What is the actual stress and factor of safety with this 3 degree rotation? d = 8.0 mm - L = 200 mm T QUESTION 4 (continued) A tubular steel shaft is being designed to transmit 225 kW at 1700 RPM, with maximum shear stress limited to not more than 30 MPa. If the outside diameter of the shaft is 75 mm, what is the minimum wall thickness for the shaft? QUESTION 5 (5+5 = 10 marks) P8.90 The grooved shaft shown in Figure P8.90 is made of C86100 bronze (see Appendix D for properties). The major shaft diameter is D = 50 mm, the minor shaft diameter at the groove is d = 34 mm, and the radius of the groove is = 4 mm. Determine the maximum allowable moment M that may be applied to the shaft if a factor of safety of 1.5 with respect to failure by yield is specified. M D FIGURE P8.90 Radius r M QUESTION 5 (continued) A cylindrical boiler with an OD of 2.8-m and a wall thickness of t=33 mm was fabricated from an alloy with yield stress of 335 MPa. Determine the maximum hoop stress produced by an internal pressure of 2.3 MPa. What is the maximum internal pressure if a factor of safety of 3 is required? QUESTION 6 (5+5=10 marks) A R L b B Problem 5.5-6 A freight-car axle AB is loaded approximately as shown in the figure, with the forces P representing the car loads (transmitted to the axle through the axle boxes) and the forces R representing the rail loads (transmitted to the axle through the wheels). The diameter of the axle is d = 80 mm, the distance between centers of the rails is L, and the distance between the forces P and is R is b = 200 mm. Calculate the maximum bending stress max in the axle if P = 47 kN.