Question

The cantilevered beam shown below is a sandwich beam with a plastic core and aluminum alloy faces. The member is subjected to a concentrated load at the free end. The plastic core (240mm x 200 m m in cross section) has an elastic modulus of 100 GPa and allowable normal stress of 220 MPa, while the 6 mm thick aluminum face plates have an elastic modulus of 75 GPa and allowable normal stress of 260 MPa. Question I: 118 marks] (a) Determine whether the composite beam can support the loading shown. (remember to check for failure in each material) 12 marks] (b) Give the maximum load P the beam can support without causing failure. P 50 kN 6 mm 200 mm 6 mm 240 mm beam cross-section 3 m 04-BS-6: Mechanics of Materials National Exams May 2016 2 of 11

Answer 1

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