Test 21 - RCC Water Tanks and Liquid-Retaining Structures

Question 1 ప్రశ్న 1

Which statement correctly describes the current design-method context for reinforced concrete liquid-retaining structures under IS 3370 (Part 2):2021?

A The working stress method remains the only permitted design method B The code uses Limit State design and the earlier working stress design method has been removed C Only ultimate strength is checked; serviceability need not be considered D IS 3370 no longer refers to IS 456 for reinforced concrete design

Question 2 ప్రశ్న 2

For what liquid-temperature range are the recommendations of IS 3370 (Parts 1 and 2):2021 generally intended, assuming the aqueous liquid has no detrimental action requiring special measures?

A Only liquids below 10°C B Only liquids between 10°C and 30°C C Aqueous liquids generally not exceeding 50°C D All liquids at any temperature without restriction

Question 3 ప్రశ్న 3

For durability classification under IS 3370 (Part 1):2021, how should parts of a structure retaining liquid or enclosing the space above the liquid normally be treated?

A As not less than severe exposure under IS 456 B As mild exposure irrespective of the stored liquid C As moderate exposure only when the tank is underground D As extreme exposure in every case

Question 4 ప్రశ్న 4

Under the general material requirements of IS 3370 (Part 1):2021, which combination applies to reinforced concrete used for liquid-retaining structures before considering any permitted special exception?

A Minimum M20, 250 kg/m³ cementitious content and maximum free water-cementitious ratio 0.50 B Minimum M25, 300 kg/m³ cementitious content and maximum free water-cementitious ratio 0.50 C Minimum M30, 350 kg/m³ cementitious content and maximum free water-cementitious ratio 0.45 D Minimum M40, 380 kg/m³ cementitious content and maximum free water-cementitious ratio 0.40

Question 5 ప్రశ్న 5

Which statement correctly describes the limited M25 exception given in IS 3370 (Part 1):2021 for reinforced concrete tanks?

A M25 may replace M30 for every tank of any capacity B M25 may be used for small tanks up to 50 m³ where providing M30 is difficult, but the exception does not apply in coastal, highly polluted or aggressive-liquid conditions such as sewage C M25 is permitted only for prestressed tanks D M25 is permitted only when the water-cementitious ratio is increased above 0.60

Question 6 ప్రశ్న 6

How is nominal cover to reinforcement determined for an RCC liquid-retaining member under IS 3370 (Part 1):2021?

A A universal 20 mm cover is used for every tank B A universal 40 mm cover is prescribed regardless of exposure C It is determined from IS 456 for the relevant exposure condition, subject to the liquid-retaining exposure classification D Cover is unnecessary if crack width is checked

Question 7 ప్రశ్న 7

Which loading principle is fundamental when designing an RCC tank or reservoir under IS 3370?

A Only the full condition needs to be considered because an empty tank has no liquid pressure B Only the empty condition needs to be considered for underground tanks C Both full and empty conditions, together with other relevant loads, should be considered so that critical effects are captured D The liquid load may be ignored whenever dead load is larger

Question 8 ప్రశ్న 8

Which statement correctly distinguishes the liquid level used in the ordinary serviceability and collapse checks under IS 3370 (Part 2):2021?

A Lowest supply level is used for both SLS and ULS B Full Supply Level is used for serviceability, while Maximum Top Level or the level under maximum overflow rate is considered for collapse design C Maximum Top Level is used only for crack-width serviceability checks D The liquid level has no effect on design load

Question 9 ప్రశ్న 9

A tank contains water to a depth of 4.5 m. Taking the unit weight of water as 9.81 kN/m³, what hydrostatic pressure acts at the bottom?

A 22.1 kN/m² B 36.0 kN/m² C 44.1 kN/m² D 88.3 kN/m²

Question 10 ప్రశ్న 10

A vertical tank wall retains 4.0 m depth of water with unit weight 10 kN/m³. What is the total horizontal hydrostatic thrust on a one-metre-wide strip of wall, and where does it act above the base?

A 40 kN/m acting at 2.0 m B 80 kN/m acting at 1.33 m C 80 kN/m acting at 2.0 m D 160 kN/m acting at 1.33 m

Question 11 ప్రశ్న 11

If the 4.0 m high wall in the previous question behaves as a vertical cantilever fixed at its base, what bending moment at the base is caused by the water pressure alone?

A 53.3 kN·m/m B 80.0 kN·m/m C 106.7 kN·m/m D 160.0 kN·m/m

Question 12 ప్రశ్న 12

Why is an RCC water-tank member not adequately designed merely by satisfying ultimate flexural strength?

A Because water tanks do not carry bending moments B Because liquid tightness, crack control, deflection and durability are critical serviceability requirements in addition to ultimate strength C Because service loads are always larger than ultimate loads D Because reinforcement is used only for temperature effects in tanks

Question 13 ప్రశ్న 13

What leakage performance characterizes Tightness Class 1 under IS 3370 (Part 2):2021?

A No leakage of any kind is permitted and prestressing is mandatory B Leakage is limited to a small amount, with some surface staining or damp patches acceptable C Leakage may be unlimited provided structural strength is adequate D Class 1 applies only to roofs and not to tank walls

Question 14 ప్రశ్న 14

Which description corresponds to Tightness Class 2 under IS 3370 (Part 2):2021?

A Leakage is to be minimal and appearance should not be impaired by staining B Surface staining is freely permitted and leakage need not be limited C No leakage whatsoever is permitted without any special measures D Class 2 relates only to structural strength and has no leakage requirement

Question 15 ప్రశ్న 15

What is the defining leakage requirement of Tightness Class 3 under IS 3370 (Part 2):2021?

A Some damp patches are acceptable B Leakage may occur provided it does not reach the outer face C No leakage is permitted, and special measures such as prestressing or an impermeable liner are generally required D Only reinforcement spacing is controlled; leakage is not considered

Question 16 ప్రశ్న 16

For Tightness Class 1, what limiting crack width is specified for a crack expected to pass through the full thickness of the section when no compression block remains?

A 0.05 mm B 0.10 mm C 0.20 mm D 0.30 mm

Question 17 ప్రశ్న 17

Which statement correctly summarizes the ordinary crack-control options for Tightness Class 2?

A A 0.3 mm full-thickness crack is always acceptable B A 0.2 mm limit may be used while avoiding full-thickness cracks unless suitable measures such as liners or water-bars are provided; alternatively a 0.1 mm crack limit may be adopted C Crack width is irrelevant if M30 concrete is used D All sections must be prestressed regardless of crack width

Question 18 ప్రశ్న 18

Which crack-control statement is appropriate for Tightness Class 3?

A A 0.30 mm crack is acceptable if the member is thick B The limiting crack width is 0.10 mm, full-thickness cracks should be avoided, and a compression zone of at least 50 mm should be available, with special water-tightness measures generally required C Crack width need not be checked because a liner automatically carries structural loads D Only the outer face requires reinforcement

Question 19 ప్రశ్న 19

Which statement best describes the role of movement joints in a liquid-retaining RCC structure?

A They are provided only to reduce reinforcement quantity and need not be watertight B They are intended to accommodate relative movement while special joint details and, where required, water-bars maintain liquid tightness C They must always interrupt both concrete and reinforcement in exactly the same manner D They are used only in steel tanks

Question 20 ప్రశ్న 20

Which statement about the current minimum-reinforcement provisions for RCC tank walls, floors and roofs is most accurate?

A The ordinary 0.12 percent slab minimum from IS 456 automatically governs every tank member B IS 3370 Part 2 specifies minimum reinforcement in two orthogonal directions within defined surface zones, and the current amended Table 5 should be used for the applicable tank type and geometry C Minimum reinforcement is required only in the direction of calculated bending D No minimum reinforcement is needed if the tank is watertight on the day of testing

Question 21 ప్రశ్న 21

Which mapping of the IS 3370 Part 4 design-table sections is correct?

A Section 1 circular tanks, Section 2 plates, Section 3 rectangular tanks B Section 1 plates, Section 2 rectangular tanks, Section 3 circular tanks C Section 1 foundations, Section 2 columns, Section 3 beams D Section 1 prestressed tanks, Section 2 steel tanks, Section 3 masonry tanks

Question 22 ప్రశ్న 22

At a depth where the internal water pressure in a circular tank is 30 kN/m², the tank has an internal diameter of 8.0 m. Using thin-cylinder equilibrium and neglecting local base-restraint effects, what circumferential membrane tension is developed per metre height of wall?

A 60 kN/m B 90 kN/m C 120 kN/m D 240 kN/m

Question 23 ప్రశ్న 23

Which statement best describes the structural behaviour of a rectangular RCC tank wall?

A It must always be designed as a one-way vertical cantilever regardless of its dimensions and edge restraints B It may resist liquid pressure through both vertical and horizontal bending, depending on wall proportions and support or continuity conditions C It carries only direct hoop tension like a circular tank D It is free from bending if crack-width reinforcement is provided

Question 24 ప్రశ్న 24

An underground RCC tank is empty while groundwater rises around it. Which design issue becomes especially important?

A Only internal hydrostatic pressure B External groundwater pressure and overall flotation or uplift stability C Hoop tension from the stored liquid D Only roof live load because the empty tank has no other actions

Question 25 ప్రశ్న 25

For a tank intended to retain drinking, domestic or treated water, which statement correctly describes the roof requirements under IS 3370 (Part 2):2021?

A The roof need not be liquid-tight because it is above the stored water B The roof should be made liquid-tight and provided with suitable drainage slopes; protective measures shall also be taken at its underside against corrosion due to condensation and chlorine attack, and it shall satisfy the applicable liquid-retaining cover and crack-width requirements C The roof should be designed only for its self-weight and ordinary building-slab crack limits D The roof must always be left unreinforced to avoid restraint cracking

Answer Key || సమాధానాల పట్టిక

Related Quizzes || సంబంధిత క్విజ్‌లు

Civil HMWSSB, Unit 3 - Cement Concrete and Steel Structures Quiz

TGPSC HMWSSB Quiz

Answer Key సమాధానాల పట్టిక

Related Quizzes సంబంధిత క్విజ్‌లు