Question

End of Semester 1, 2018 STEN2002 Civil Engineering Materials (Total Mark for Question 4: 18) Part A - Question 4 7 complicated frame that was difficult to analyse Using a rectangular strain gauge rosette, the actual strains at point A have been recorded while being subjected to test loads. It is necessary to determine the principal stresses and shear stresses in the actual beam subject to the test loads to check whether the stresses assumed in the design of the beam were accurately modelled. A steel beam in an industrial structure is part ofa 720 E45 S45 80=20u Figure 4: Recorded strains in rectangular rosette under test loads It is reasonable to assume that the stress in the x-axis (out of the page) is 0 MPa E 200 GPa; 0.3 For the steel used in the beam assume: Using the strains recorded by the rosette, calculate the normal strains in the7 and y axis direction and the shear strain in the z-y plane. a) (4 marks) b) Using Mohr's circle of strain (Mohr's circle must be shown and used), determine the magnitude of the principal strains. (6 marks) Calculate the principal normal stresses. c) (4 marks) d) Calculate the maximum shear stresses in the z-y plane of the steel beam. (2 marks) Calculate the absolute maximum shear stress e) (2 marks) End of Part A 1 Eg0 820

Answer 1

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2 Sirdns Cenib 201 820 2 ladia 20- 20 2. - SUOu

mch ircle Seu) Slans Qz + Ey 2-- TUO 420

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GnE max G 2 2 MAX 12-6