3. The Z section in Fig. (a) 1s formed from aluminum alloy 2024-T3 sheet. What compressive stress will start local buckling of an element of the member? kw=2.9 E=10,700,000psi .75 0.65 Flange 1.05 Web✓

Question 6 The state of plane stress shown in Fig. Q6 occurs at a critical point of a steel component. The tensile yield strength oy 200 MPa for the grade of steel used. Use Mohr's circle to determine the factor of safety k with respect to yield using = (a) the maximum-shearing-stress criterion, and (b) the maximum-distortion-energy criterion. 40 MPa 25 MPa Fig. Q6 80 MPa

Problem 4 For the shown structure, AB is made by A-36 steel (Est = 200GPA, ast = 12 x 10-67 °C) and BC is made by %| 73.1GPA, aal = 23 × 10-6/ °C). Both AB and BC are having circular cross sectional area. The aluminum (Eal gap between C and the rigid wall at D is initially 0.15 mm. For the following situations, find (1) reaction forces at fixed end A and D (2) Plot the axial load diagram P=400 kN applied at B and there is no temperature -0.15 тm 600 mm 600 mm vi. change vii. P=400 kN applied and temperature in both AB and BC 25°C segments had dropped AT P=400 kN applied, however, the temperature in AB increased ATst = 25°C and temperature in BC decreased ATal = 25°C vii. B. 25 mm 50 mm

PROBLEM 1) An aluminum bar carries the axial loads at the positions shown. If E=70GPA, compute the total deformation of the bar. Assume that the bar is suitably braced to prevent buckling. 0.4m D What is the axial stress o Ag in Pa? 10KN 0.8m 0.4m B 5KN 0.6m 20KN A=800 mm? A=1,200 mm²