Question

solve this structural design question using australian standards

(a) The diagram shown below (Figure 3) represents a statically determinate beam ABCDE carrying a 1 kN point load which moves along the length of the beam. The support at A is fixed, B is an internal hinge and D is a roller support. Develop the following influence lines for this beam showing the values at all points A, B, C, D and E. All dimensions are in mm. Influence line for the bending moment at A, MA i. (25 marks) Influence line for the vertical reaction at D, Roy. (25 marks) iii Influence line for the shear force at c, Vc. (20 marks) 1 kN B A 1500 5000 2500 2000 Figure 3. Beam ABCDE (b) What is resonance and why is it critical in structural design? How can the resonance be avoided while designing the structures? (30 marks) (c) What is critical damping? Will a structure vibrate when subjected to external excitation if it has a damping 30% of the critical damping value and why? (20 marks)

Answer 1

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