Unit-II Dams and Hydraulic Structures MCQ PDF

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Unit-II Dams and Hydraulic Structures MCQ...

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When the upstream face of a gravity dam is vertical, then the intensity of water pressure at the water surface and at the base respectively will be A) 0 and wH212 B) wH2/2and wH2/3 C) wH and 0 D) O and wH where w is unit weight of water and H is the depth of water. ANSWER: D The uplift pressure on a dam can be controlled by A) constructing cutoff under upstream face B) constructing drainage channels between the dam and its foundation C) by pressure grouting in foundation D) all of the above ANSWER: D The uplift pressure on the face of a drainage gallery in a dam is taken as A) hydrostatic pressure at toe B) average of hydrostatic pressure at toe and heel C) two-third of hydrostatic pressure at toe plus one-third of hydrostatic pressure at heel D) none of the above ANSWER: D Horizontal acceleration due to earthquake results in A) hydrodynamic pressure B) inertia force into the body of the dam C) both (a) and (b) D) none of the above ANSWER: D Hydrodynamic pressure due to earthquake acts at a height of A) 3H/47I above the base B) 3H747t below the water surface C) 4H/371 above the base D) 4H737t below the water surface where H is the depth of water. ANSWER: C The major resisting force in a gravity dam is A) water pressure B) wave pressure C) self-weight of dam D) uplift pressure ANSWER: C When the reservoir is full, the maximum compressive force in a gravity dam is produced A) at the toe B) at the heel

C) within the middle third of base D) at centre of base ANSWER: A The maximum permissible eccentricity for no tension at the base of a gravity dam is A) B/2 B) B/3 C) B/4 D) B/6 ANSWER: D Presence of tail water in a gravity dam A) increases the principal stress B) decreases the principal stress Ci) increases the shear stress D) increase and decreases in the shear stress ANSWER: D For wave action in dams, the maximum height of free board is generally taken to be equal to A) 0.5 hw B) 0.75 hw C) 1.25 hw D) 1.50 hw where hw is height of wave. ANSWER: D As compared to gravity dams, earthen dams A) are costlier B) are less susceptible to failure C) require sound rock foundations D) require less skilled labor ANSWER: D

To minimize thermal stresses traditional mass concrete is built in A) Separate Blocks B) Monolithic blocks C) None of the above D) All of the above ANSWER: D The main purpose of curtain grouting is/are A) Control seepage B) Increase silt pressure C) Reduce silt Pressure D) Reduce wave pressure ANSWER: A

The main purpose of curtain grouting is A) Reduce uplift pressure B) Increase uplift pressure C) All of the above D) None of the above ANSWER: A Consolidation grouting is A) Horizontal Grouting B) Vertical Grouting C) Inclined Grouting D) None of the above ANSWER: A Minor cracks,fissures and defects can be rectified by A) Pressure grouting B) curtain grouting C) consolidation grouting D) relief drains ANSWER: C Consolidation grouting and Curtain grouting are useful for A) Dam body treatment B) Dam foundation rock treatment C) all of the above D) none of the above ANSWER: C Stability of the gravity dams can be improved by A) Prestressing method B) Construction of downstream shoulder C) only a D) a and b ANSWER: D Inclinometer are installed to have check on A) internal deformation B) external deformation C) surface cracks D) all of the above ANSWER: A Settlement in dam can be monitored by A) EDM B) Contour maps

C) Both a and b D) None of the above ANSWER: A Thin cylindrical theory is adopted for design of A) earthen dam B) Arch gravity dam C) Buttress dam D) all of the above ANSWER: B Elastic theory and trial lad analysis are carried out for A) Earthen dam B) Gravity dam C) Arch dam D) none of the above ANSWER: C The reduction in the volume of the concrete can be achieved by A) Gravity dam B) Arch gravity dam C) All of the above D) none of the abov ANSWER: B Arch gravity dams can fail by A) overturning B) over-stressing of abutments C) sliding D) all of the above ANSWER: B Arch gravity dams transfers load to its A) abutments B) foundation C) all of the above D) none of the above ANSWER: A...