CIVE 310 Exam 1, Fall 2010

AUB-CEE-CIVE 310 Mechanics of Materials Saad - Fall 2010-11 Exam 1 November 12, 2010 90 minutes Problem 1 (25 Points) The steel members BE and AD each has a 6mm x 18mm cross-sectional area. Knowing that E=200GPa, determine the deflections of points A, B, and C of rigid member ABC. Problem 2 (25 Points) (a) Given that all members are made of steel with an ultimate stress of 400MPa. Using a factor of safety of 2.0, calculate the required cross-sectional areas for square members AB and ED. (b) The pins on the frame at A and E each have a diameter of 8mm. If these are subjected to double shear, determine the average shear stress in each pin. 1 P1 = P2 = 4KN AUB-CEE-CIVE 310 Mechanics of Materials Saad - Fall 2010-11 Problem 3 (25 Points) The bar shown below is made of aluminum (E = 70GPa). It is fixed at A and D, and loaded with two axial loads of 100KN and 50 KN at B and C respectively. Determine the maximum normal stress in the bar. Area of AB = 6.0 mm2 Area of BD = 2.0 mm2 Problem 4 (25 Points) A horizontal rigid beam is supported by three bar elements. Bars AB and CD are made of steel (E = 200GPa, α = 12x10-6 / C). Bar EF is made of a Titanium Alloy (E = 120GPa, α = 21x10 ̊� -6 / C). All ̊� Bars have the same Length, L = 500mm, the same cross-sectional Area, A = 25mm2, and are equally spaced at a distance d = 250mm. If the temperature in the assembly increases by 60 C, ̊� determine (a) the normal stresses in the bars, and (b) the angle of tilt of the rigid beam. 2 5 m 5 m 5 m A B 100KN 50KN C D