Test 23 - Classification and Selection of Dams

Question 1 ప్రశ్న 1

Which set correctly matches three common purpose-based classifications of dams?

A Storage dam—is defined by concrete construction; diversion dam—is defined by earthfill construction; detention dam—is defined by arch action B Storage dam—must always remain empty; diversion dam—stores all annual runoff; detention dam—exists only to generate hydropower C Storage dam—impounds water for later use; diversion dam—raises or controls water level for diversion; detention dam—temporarily stores floodwater to moderate downstream flow D Storage, diversion and detention are classifications based only on the construction material

Question 2 ప్రశ్న 2

A concrete gravity dam resists the major external water load primarily by which mechanism?

A Arch action transmitting most of the load horizontally to the abutments B The weight and internal strength of the dam acting to resist sliding and overturning C Tension cables anchored across the valley D A thin upstream slab supported only by downstream buttresses

Question 3 ప్రశ్న 3

What is the characteristic load-transfer mechanism of an arch dam?

A It transmits a major part of the reservoir load through arch action into the valley abutments B It depends only on a wide soil foundation and does not require abutment resistance C It transfers all load vertically through a downstream earth berm D It relies on loose rock fragments to dissipate hydrostatic pressure

Question 4 ప్రశ్న 4

Which description most accurately represents a buttress dam?

A A homogeneous earth embankment with no internal drainage B A massive concrete section relying only on its full solid weight C A rockfill embankment with an impervious central core D A watertight upstream face or deck supported at intervals by downstream buttresses

Question 5 ప్రశ్న 5

Which pair consists entirely of embankment-dam types?

A Gravity dam and arch dam B Earthfill dam and rockfill dam C Buttress dam and arch dam D Gravity dam and buttress dam

Question 6 ప్రశ్న 6

Why is an impervious core, membrane or equivalent seepage-control element commonly required in a rockfill dam?

A Because well-compacted rockfill is normally more watertight than concrete B Because the impervious element is used only to increase turbine head C Because the rockfill provides much of the structural mass but is generally too pervious to serve alone as the water barrier D Because it converts the dam structurally into an arch dam

Question 7 ప్రశ్న 7

A well-designed earthfill dam commonly controls seepage through the embankment by using which arrangement?

A An impervious zone together with properly designed filters and drains B Only an unprotected crest opening for overflow C A system of arch ribs transferring all load to the abutments D No zoning or drainage because compacted soil is always perfectly impermeable

Question 8 ప్రశ్న 8

Under classification by hydraulic design, what is an overflow dam?

A A dam intended to fail safely whenever the reservoir rises B A dam that must remain completely dry during floods C Any embankment dam without a spillway D A dam designed so that discharge can pass over its crest or designated overflow section without unacceptable erosion or structural damage

Question 9 ప్రశ్న 9

Why are ordinary earthfill and rockfill dam sections generally treated as nonoverflow sections?

A Because embankment dams cannot contain outlet works B Because embankment dams cannot store water C Because embankment materials and slopes can be severely eroded by uncontrolled overtopping D Because earthfill and rockfill dams are always located away from rivers

Question 10 ప్రశ్న 10

A proposed dam site is a narrow V-shaped gorge with steep, competent rock abutments. If other project factors are also favorable, which dam type is especially well matched to this valley geometry?

A Very long homogeneous earth dam selected solely because the valley is narrow B Arch dam C Low diversion weir selected without regard to required storage D Earth dam chosen because arch action requires weak abutments

Question 11 ప్రశ్న 11

A dam site lies in a broad valley with considerable depth of soil over bedrock and large quantities of suitable compactable soil available nearby. Which type would generally deserve strong consideration?

A Earthfill dam B Thin arch dam C Multiple-arch buttress dam selected only for its curvature D Concrete arch dam requiring major thrust transfer into weak soil abutments

Question 12 ప్రశ్న 12

A proposed high dam site has sound rock foundation and abutments, but suitable earthfill material is scarce while concrete aggregate and cement supply are practical. Which statement is most defensible at the screening stage?

A Foundation conditions and material availability have no influence on dam-type selection B An earthfill dam must be selected regardless of material haul distance C A rockfill dam must be selected even if adequate rockfill is unavailable D A concrete dam such as a gravity type may be competitive and should be evaluated

Question 13 ప్రశ్న 13

At a relatively narrow valley with high rocky walls, abundant sound rock is available from required excavations. Which alternative may become attractive if seepage control and spillway arrangements can be satisfactorily provided?

A Homogeneous silt dam with no drainage B Rockfill dam C Arch dam regardless of abutment quality D Any dam type, because construction-material availability is irrelevant

Question 14 ప్రశ్న 14

Why are sound rock abutments especially critical for a thin arch dam?

A Because an arch dam cannot touch the valley sides B Because the abutments are intended to remain completely unstressed C Because the dam transmits substantial arch thrust into the abutments D Because the dam carries all water load through an earth core

Question 15 ప్రశ్న 15

Which foundation condition most directly supports consideration of a conventional concrete gravity dam?

A An unknown foundation because gravity dams do not transfer load to the ground B A very weak compressible clay deposit accepted without treatment C Deep loose saturated sand with no liquefaction assessment D A competent foundation capable of safely carrying high compressive and shear reactions and controlling seepage

Question 16 ప్రశ్న 16

Compared with a solid concrete gravity dam of similar height, what is a potential structural-material advantage of a buttress dam at a suitable site?

A It can reduce concrete volume by using a supported upstream deck or heads rather than a fully solid section B It eliminates all foundation reactions C It requires no reinforcement or structural analysis D It can be founded safely on any soil without settlement checks

Question 17 ప్రశ్న 17

Which statement best describes the role of local construction materials in selecting a dam type?

A Material availability matters only after the dam has been completely constructed B The most economical type is often influenced strongly by whether suitable earth, rock and concrete materials are available within reasonable haul distances C All dam types require identical quantities and processing of local materials D Imported material is always cheaper than suitable material from project excavations

Question 18 ప్రశ్న 18

A design team selects an arch dam solely because the valley is narrow, but later investigations show highly fractured and deformable abutment rock. What is the best engineering response?

A Retain the arch dam automatically because valley shape overrides geology B Ignore the fractures because arch dams transfer no load to abutments C Reassess the dam type and foundation treatment because adequate abutment competence is fundamental to arch action D Convert the fractured abutments into an earth core without changing the design

Question 19 ప్రశ్న 19

Which description best defines a diversion dam when dams are classified according to purpose?

A A dam that must be an arch structure B A dam whose only purpose is permanent sediment storage below dead level C A dam defined solely by the use of rockfill material D A dam intended mainly to raise the upstream water level so flow can be diverted into a canal, conduit or other waterway

Question 20 ప్రశ్న 20

Which project objective most directly characterizes a detention dam used for flood management?

A Temporarily storing floodwater and releasing it at controlled rates to reduce downstream flood peaks B Maintaining the reservoir at maximum conservation level at all times C Diverting all normal river flow to hydropower turbines only D Providing an impervious core for a rockfill shell

Question 21 ప్రశ్న 21

A long embankment closes a wide valley, but the main flood spillway must pass large discharges at one section. Which arrangement is often technically reasonable?

A Remove all spillway provisions because embankments cannot coexist with concrete structures B Allow uncontrolled flood discharge over the ordinary earthfill crest C Use a composite layout with an embankment nonoverflow section and a suitably designed concrete overflow or spillway section D Use an arch section in the middle solely because the valley is wide

Question 22 ప్రశ్న 22

Why can an embankment dam sometimes be more suitable than a rigid concrete dam on a foundation that is not uniformly strong rock?

A Embankment dams transmit no load to their foundations B Embankment dams can often accommodate more foundation deformation because their fill is comparatively flexible, provided stability, settlement and seepage are properly controlled C Earthfill becomes stronger when piping occurs D Concrete dams are prohibited on every rock foundation

Question 23 ప్రశ్న 23

Which factor combination should be considered when comparing feasible dam types at a new site?

A Only maximum reservoir depth B Only the unit price of concrete C Only the preference of the equipment contractor D Valley topography, foundation and abutment geology, available materials, hydrology, appurtenant works, seismic conditions, constructability and overall economy

Question 24 ప్రశ్న 24

A preliminary study compares two alternatives for the same storage site. Alternative X is an arch dam that requires extensive stabilization of weak abutments, while Alternative Y is an earthfill dam using abundant nearby borrow on a broad saddle alignment. Which selection principle is correct?

A Compare total technical feasibility, risk, foundation treatment, appurtenant works, construction requirements and life-cycle economy before selecting the type B Select Y automatically because earth dams never need foundation treatment C Select X automatically because arch dams always use less material D Ignore foundation treatment costs because they are unrelated to dam selection

Question 25 ప్రశ్న 25

Consider the following statements about dam classification and selection: I. A gravity dam relies principally on its weight for stability. II. An arch dam is especially dependent on competent abutments. III. Earthfill and rockfill dams are embankment dams. IV. Ordinary embankment sections are generally treated as nonoverflow and require safe spillway provisions. Which option is correct?

A I and II only B I, II and III only C I, II, III and IV D II, III and IV only

Answer Key || సమాధానాల పట్టిక

Related Quizzes || సంబంధిత క్విజ్‌లు

Civil HMWSSB, Unit 5 - Hydrology and Water Resources Engineering Quiz

TGPSC HMWSSB Quiz

Answer Key సమాధానాల పట్టిక

Related Quizzes సంబంధిత క్విజ్‌లు