2.99 See Answer

Question: A beam of length L is designed

A beam of length L is designed to support a uniform load of intensity q (see figure). If the supports of the beam are placed at the ends, creating a simple beam, the maximum bending moment in the beam is qL2/8. However, if the supports of the beam are moved symmetrically toward the middle of the beam (as shown), the maximum bending moment is reduced. (a) Determine the distance a between the supports so that the maximum bending moment in the beam has the smallest possible numerical value. Draw the shear-force and bending-moment diagrams for this condition. (b) Repeat part (a) if the uniform load is replaced with a triangularly distributed load with peak intensity q0 = q at mid-span (see Fig. b).
A beam of length L is designed to support a uniform load of intensity q (see figure). If the supports of the beam are placed at the ends, creating a simple beam, the maximum bending moment in the beam is qL2/8. However, if the supports of the beam are moved symmetrically toward the middle of the beam (as shown), the maximum bending moment is reduced.
(a) Determine the distance a between the supports so that the maximum bending moment in the beam has the smallest possible numerical value. Draw the shear-force and bending-moment diagrams for this condition.
(b) Repeat part (a) if the uniform load is replaced with a triangularly distributed load with peak intensity q0 = q at mid-span (see Fig. b).





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2.99

See Answer