1. For the loaded simply supported beam shown:
Note: All parts of this question relate to the beam shown above
(a) Show that the support reactions are RL = 22·2 kN and RR = 32·8 kN. 4
(b) Draw the SFD and BMD. Use the table below when evaluating the bending moments. You may add extra values to those shown, if you consider it necessary. 32
(c) Identify the positions of any points of contraflexure. 2
(d) Find the magnitude and position of the maximum bending moment. 2
(e) State if the beam is hogging or sagging where the bending moment is greatest. 2
(f) State the value of the shear force and the bending moment at the mid-span of the beam. 2
In cross-section, the beam you are working on is a gantry girder, the maximum bending stress in the girder must not exceed 25 MN/m² and the modulus of elasticity can be assumed to be 210 GN/m².
(g) Determine a suitable size for the beam, selected from standard section tables. 6
(h) Determine the actual value of maximum stress in the chosen beam. 4
(i) Determine the radius of curvature for the chosen beam. 4
(j) Discuss what factors would need to be incorporated into your calculations in order to give more accurate answers, and indicate how this can be achieved. 2
Distance from LHE (m)
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Moments (kN x m)
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M (kNm)
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2
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3
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4
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5
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9
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11
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13
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15
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