Question

Q-1 A solid circular rod with a diameter d = 18 mm is shown in Figure Q-3. The rod is made of an aluminum alloy that has an elastic modulus E = 72 GPa and a Poisson's ratio v=0.32. When subjected to the axial load P, the diameter of the rod decreases by 0.025 mm. For a factor of safety of 1.75, a) Determine the magnitude of the safe allowable load P. pts.] b) If we have a 12 mm diameter hole theough the rod, making it a hollow member (a pipe), other things remaining the same as in part (a), determine the magnitude of load P [16 pts.) [18

Answer 1

5 a d E = 72 GPO V 0.32 Sa Ed Sd = -0.025mm decreases ds 18 mm Lateral strain Ed te Poisson's Ratio - longitudinal strain 3 1 4:34 X10 El -les -(-0,025)* 0:32 18 allowable = A. ELE F.o.5 **(0.018)?x 4.34 X10 3 x 72x109 1.75 v 79.516x103 1-75 P = 45.4377 KN b & di= 12mm when d = 18mm A I ( do ² di 2) = 7 4 ( 0.0182 0-0122) = 1.4137 x104m2 Р 14:14 Ee = 4:34X10 -3 same Pallowable = A. EXX E FOS 1-4137x 10-4x 434 x 10-3x 72x109 1.75 Pallow 25.243KN