TGPSC HMWSSB Manager 2015 Paper 2 · Question 122
Question 122 of the TSPSC Manager (Engineering), HMWSSB, 2015: Paper 2 (Civil Engineering) (1 November 2015). Try it first, then open the answer and explanation.
A simply supported beam of span L and uniform flexural rigidity EI is subjected a pre-stressing force of magnitude P, at an eccentricity e below the neutral layer, parallel to the axis of the member. The displacement of the beam at a location L/4 from the support is ______.
- PeL²/4EI
- PeL²/8EI
- PeL²/2EI
- PeL²/EI
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Answer: (2) PeL²/8EI
A straight tendon at eccentricity e gives a uniform moment M = Pe along the span, and a simply supported beam under uniform moment cambers upward by ML²/8EI = PeL²/8EI, the keyed value (this is the mid-span camber). Strictly, at L/4 the expression Mx(L − x)/2EI gives 3PeL²/32EI, which is not among the options. (Official final key; some sources differ.)