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On: July 12, 2023 Posted in Internet Comments: 0 Views: 74

Concrete Technology and Design Solved MCQs

1.	The temperature reinforcement in the vertical slab of a T-shaped R.C. retaining wall is
A.	not needed
B.	provided equally on inner and front faces
C.	provided more on inner face than on front face
D.	provided more on front face than on inner face
Answer» D. provided more on front face than on inner face

2.	Bulking of sand is maximum if moisture content is about
A.	2 %
B.	4 %
C.	6 %
D.	10 %
Answer» B. 4 %

3.	Diagonal tension in a beam
A.	is maximum at neutral axis
B.	decreases below the neutral axis and increases above the neutral axis
C.	increases below the neutral axis and decreases above the neutral axis
D.	remains same
Answer» C. increases below the neutral axis and decreases above the neutral axis

4.	According to IS: 4561978, the column or the strut is the member whose effective length is greater than
A.	the least lateral dimension
B.	2 times the least lateral dimension
C.	3 times the least lateral dimension
D.	4 times the least lateral dimension
Answer» C. 3 times the least lateral dimension

5.	When shear stress exceeds the permissible limit in a slab, then it is reduced by
A.	increasing the depth
B.	providing shear reinforcement
C.	using high strength steel
D.	using thinner bars but more in number
Answer» A. increasing the depth

6.	The diameter of ties in a column should be
A.	more than or equal to one fourth of diameter of main bar
B.	more than or equal to 5 mm
C.	more than 5 mm but less than one-fourth of diameter of main bar
D.	more than 5 mm and also more than one-fourth of diameter of main bar
Answer» D. more than 5 mm and also more than one-fourth of diameter of main bar

7.	In counterfort retaining walls, the main reinforcement in the stem at support is
A.	not provided
B.	provided only on inner face
C.	provided only on front face
D.	provided both on inner and front faces
Answer» B. provided only on inner face

8.	Due to shrinkage stresses, a simply supported beam having reinforcement only at bottom tends to
A.	deflect downward
B.	deflect upward
C.	deflect downward or upward
D.	none of the above
Answer» A. deflect downward

9.	The purpose of reinforcement in pre-stressed concrete is
A.	to provide adequate bond stress
B.	to resist tensile stresses
C.	to impart initial compressive stress in concrete
D.	all of the above
Answer» C. to impart initial compressive stress in concrete

10.	Select the correct statement
A.	elastic modulus of high tensile steel is nearly the same as that of mild steel
B.	elastic modulus of high tensile steel is more than that of mild steel
C.	carbon percentage in high carbon steel is less than that in mild steel
D.	high tensile steel is cheaper than mild steel
Answer» A. elastic modulus of high tensile steel is nearly the same as that of mild steel

11.	Due to circumferential action of the spiral in a spirally reinforced column
A.	capacity of column is decreased
B.	ductility of column reduces
C.	capacity of column is decreased but ductility of column increases
D.	both the capacity of column and ductility of column increase
Answer» D. both the capacity of column and ductility of column increase

12.	For concreting of heavily reinforced sections without vibration, the workability of concrete expressed as compacting factor should be
A.	0.75 – 0.80
B.	0.80 – 0.85
C.	0.85 – 0.92
D.	above 0.92
Answer» D. above 0.92

13.	Workability of concrete is directly proportional to
A.	aggregate cement ratio
B.	time of transit
C.	grading of the aggregate
D.	all of above
Answer» C. grading of the aggregate

14.	Critical section for shear in case of flat slabs is at a distance of
A.	effective depth of slab from periphery of column/drop panel
B.	d/2 from periphery of column/capital/ drop panel
C.	at the drop panel of slab
D.	at the periphery of column
Answer» B. d/2 from periphery of column/capital/ drop panel

15.	For road pavements, the cement generally used, is
A.	ordinary portland cement
B.	rapid hardening cement
C.	low heat cement
D.	blast furnace slag cement
Answer» B. rapid hardening cement

16.	Pick up the incorrect statement from the following:
A.	space between the exterior walls of a warehouse and bag piles should be 30 cm
B.	cement bags should preferably be piled on wooden planks
C.	width and height of the pile should not exceed 3 m and 2.70 m respectively
D.	none of these
Answer» D. none of these

17.	For a slab supported on its four edges with corners held down and loaded uniformly, the Marcus correction factor to the moments obtained by Grashoff Rankine’s theory
A.	is always less than 1
B.	is always greater than 1
C.	can be more than 1
D.	can be less than 1
Answer» A. is always less than 1

18.	Addition of pozzolana to ordinary port land cement, causes
A.	decrease in early strength
B.	reduction in chemical action with sulphates
C.	increase in shrinkage
D.	all the above
Answer» D. all the above

19.	Pick up the correct statement from the following:
A.	the maximum size of a coarse aggregate, is 75 mm and minimum 4.75 mm
B.	the maximum size of the fine aggregate, is 4.75 mm and minimum 0.075 mm
C.	the material having particles of size varying from 0.06 mm to 0.002 mm, is known as silt
D.	all the above
Answer» D. all the above

20.	For construction of structures in sea water, the cement generally preferred to, is
A.	portland-pozzolana cement
B.	quick setting cement
C.	low heat portland cement
D.	rapid hardening cement
Answer» A. portland-pozzolana cement

21.	Curing of pavements, floors, roofs and slabs, is done by
A.	membrane method
B.	ponding method
C.	covering surface with bags
D.	sprinkling water method
Answer» B. ponding method

22.	Pick up the correct statement from the following:
A.	construction joints are necessarily planned for their locations
B.	expansion joints are provided to accommodate thermal expansion
C.	construction joints are provided to control shrinkage cracks
D.	all the above
Answer» D. all the above

23.	The bulk density of aggregates, depends upon
A.	shape
B.	grading
C.	compaction
D.	all the above
Answer» D. all the above

24.	In symmetrically reinforced sections, shrinkage stresses in concrete and steel are respectively
A.	compressive and tensile
B.	tensile and compressive
C.	both compressive
D.	both tensile
Answer» B. tensile and compressive

25.	The main object of compaction of concrete, is:
A.	to eliminate air holes
B.	to achieve maximum density
C.	to provide intimate contact between the concrete and embedded materials
D.	all the above
Answer» D. all the above

26.	Which of the following has high tensile strength?
A.	plain hot rolled wires
B.	cold drawn wires
C.	heat treated rolled wires
D.	all have same tensile strength
Answer» B. cold drawn wires

27.	Concrete gains strength due to
A.	chemical reaction of cement with sand and coarse aggregates
B.	evaporation of water from concrete
C.	hydration of cement
D.	all the above
Answer» C. hydration of cement

28.	To determine the modulus of rupture, the size of test specimen used is
A.	150 × 150 × 500 mm
B.	100 × 100 × 700 mm
C.	150 × 150 × 700 mm
D.	100 × 100 × 500 mm
Answer» C. 150 × 150 × 700 mm

29.	Tricalcium aluminate (C3A)
A.	reacts fast with water
B.	generates less heat of hydration
C.	causes initial setting and early strength of cement
D.	does not contribute to develop ultimate strength
Answer» B. generates less heat of hydration

30.	If the various concrete ingredients i.e. cement, sand and aggregates are in the ratio of 1:3:6, the grade of concrete, is
A.	m 100
B.	m 150
C.	m 200
D.	m 250
Answer» A. m 100

31.	Admixtures which cause early setting and hardening of concrete are called
A.	workability admixtures
B.	accelerators
C.	retarders
D.	air entraining agents
Answer» B. accelerators

32.	Pick up the correct statement from the following:
A.	sand stones may be divided into calcareous, siliceous and ferruginous sand stones
B.	concrete using sand stones, cracks due to excessive shrinkage
C.	broken bricks produce a concrete having good fire resisting qualities
D.	all the above
Answer» D. all the above

33.	Pick up the incorrect statement from the following:
A.	admixtures accelerate hydration
B.	admixtures make concrete water proof
C.	admixtures make concrete acid proof
D.	admixtures give high strength
Answer» A. admixtures accelerate hydration

34.	For a reinforced concrete section, the shape of shear stress diagram is
A.	wholly parabolic
B.	wholly rectangular
C.	parabolic above neutral axis and rectangular below neutral axis
D.	rectangular above neutral axis and parabolic below neutral axis
Answer» C. parabolic above neutral axis and rectangular below neutral axis

35.	Allowable shear strength of concrete, depends upon
A.	shear strength
B.	tensile strength
C.	compressive strength
D.	none of these
Answer» A. shear strength

36.	In slump test, each layer of concrete is compacted by a steel rod 60 cm long and of 16 mm diameter for
A.	20 times
B.	25 times
C.	30 times
D.	50 times
Answer» B. 25 times

37.	The individual variation between test strength of sample should not be more than
A.	±5 % of average
B.	± 10 % of average
C.	± 15 % of average
D.	±20 % of average
Answer» C. ± 15 % of average

38.	Pick up the incorrect statement from the following:
A.	concrete for which preliminary tests are conducted, is called controlled concrete
B.	bulking of sand depends upon the fineness of grains
C.	concrete mix 1 : 6 : 12, is used for mass concrete in piers
D.	all the above
Answer» D. all the above

39.	The slab is designed as one way if the ratio of long span to short span is
A.	less than 1
B.	between 1 and 1.5
C.	between 1.5 and 2
D.	greater than 2
Answer» D. greater than 2

40.	For the construction of cement concrete dams, the maximum permissible size of the aggregates, is
A.	40 mm
B.	50 mm
C.	60 mm
D.	70 mm
Answer» A. 40 mm

41.	Pick up the incorrect statement from the following:
A.	with passage of time, the strength of cement increases
B.	with passage of time, the strength of cement decreases
C.	after a period of 24 months, the strength of cement reduces to 50%
D.	the concrete made with storage deteriorated cement, gains strength with time
Answer» A. with passage of time, the strength of cement increases

42.	To hydrate 500kg of cement full water needed, is
A.	100 kg
B.	110 kg
C.	120 kg
D.	130 kg
Answer» D. 130 kg

43.	Pick up the correct statement from the following:
A.	a highly absorptive aggregate reduces the workability of concrete considerably
B.	the specific gravity of aggregate is important for the determination of the moisture content
C.	the absorption and porosity of an aggregate influence the property of the concrete
D.	all the above
Answer» D. all the above

44.	In a counterfort retaining wall, the main reinforcement in the stem at mid span is provided on
A.	front face only
B.	inner face only
C.	both front face and inner face
D.	none of the above
Answer» A. front face only

45.	Under normal conditions using an ordinary cement, the period of removal of the form work, is:
A.	7 days for beam soffits
B.	14 days for bottom slabs of spans 4.6 m and more
C.	21 days for bottom beams over 6 m spans
D.	all the above
Answer» D. all the above

46.	Water cement ratio is generally expressed in volume of water required per
A.	10 kg
B.	20 kg
C.	30 kg
D.	50 kg
Answer» D. 50 kg

47.	To ensure constant moisture content in aggregates
A.	area of each aggregate pile should be large
B.	height of each aggregate pile should not exceed 1.50 m
C.	aggregate pile should be left for 24 hours before aggregates are used
D.	all the above
Answer» D. all the above

48.	Pick up the correct statement from the following:
A.	cement should be mixed for at least one minute
B.	10% of water is placed in the rotating drum before adding dry material
C.	10% of water is added after placing the other ingredients in the drum
D.	all the above
Answer» D. all the above

49.	The average permissible stress in bond for plain bars in tension is
A.	increased by 10% for bars in compression
B.	increased by 25% for bars in compression
C.	decreased by 10% for bars in compression
D.	decreased by 25% for bars in compression
Answer» B. increased by 25% for bars in compression

50.	Concrete mainly consists of
A.	cement
B.	aggregates
C.	water
D.	all the above
Answer» D. all the above

51.	For the construction of thin R.C.C. structures, the type of cement to be avoided, is
A.	ordinary portland cement
B.	rapid hardening cement
C.	low heat cement
D.	blast furnace slag cement
Answer» D. blast furnace slag cement

52.	Which of the following R.C. retaining walls is suitable for heights beyond 6 m?
A.	l-shaped wall
B.	t-shaped wall
C.	counterfort type
D.	all of the above
Answer» C. counterfort type

53.	For batching 1:3:6 concrete mix by volume, the ingredients required per bag of 50 kg cement, are:
A.	70 litres of sand and 120 litres of aggregates
B.	70 kg of sand and 140 litres of aggregates
C.	105 litres of sand and 140 litres of aggregates
D.	105 litres of sand and 210 litres of aggregates
Answer» D. 105 litres of sand and 210 litres of aggregates

54.	A concrete using an air entrained cement
A.	has strength less than 10% to 15%
B.	has more resistance to weathering
C.	is more plastic and workable
D.	is free from segregation and bleeding
Answer» C. is more plastic and workable

55.	Pick up the correct statement from the following:
A.	segregation is necessary for a workable concrete
B.	consistency does not affect the workability of concrete
C.	if the concrete mix is dry, the slump is maximum
D.	none of these
Answer» D. none of these

56.	The surface where two successive placements of concrete meet, is known as
A.	contraction joint
B.	expansion joint
C.	construction joint
D.	both (a) and (b)
Answer» C. construction joint

57.	A beam curved in plan is designed for
A.	bending moment and shear
B.	bending moment and torsion
C.	shear and torsion
D.	bending moment, shear and torsion
Answer» D. bending moment, shear and torsion

58.	Pick up the correct statement from the following:
A.	water cement paste hardens due to hydration
B.	during hardening cement binds the aggregates together
C.	cement provides strength, durability and water tightness to the concrete
D.	all the above
Answer» D. all the above

59.	‘Ware house pack’ of cement means
A.	full capacity of the ware house
B.	pressure exertion of the bags of upper layers
C.	pressure compaction of the bags on lower layers
D.	packing the ware house
Answer» C. pressure compaction of the bags on lower layers

60.	High carbon content in the steel causes
A.	decrease in tensile strength but increase in ductility
B.	increase in tensile strength but decrease in ductility
C.	decrease in both tensile strength and ductility
D.	increase in both tensile strength and ductility
Answer» B. increase in tensile strength but decrease in ductility

61.	Particles of 0.002 mm size are that of
A.	clay
B.	sand
C.	gravel
D.	none of these
Answer» A. clay

62.	Ultimate strength of cold drawn high steel wires
A.	increases with increase in diameter of bar
B.	decreases with increase in diameter of bar
C.	does not depend on diameter of bar
D.	none of the above
Answer» B. decreases with increase in diameter of bar

63.	The cement whose strength is a little lower than the ordinary cement during the first three months but attains afterwards the same strength, is known as
A.	low-heat portland cement
B.	rapid hardening portland cement
C.	portland blast slag cement
D.	portland pozzolana cement
Answer» A. low-heat portland cement

64.	The dimensions of a 35 litre forma for measuring aggregates by volume, are:
A.	length 30 cm, breadth 25 cm, height 30 cm
B.	length 39 cm, breadth 25 cm, height 32 cm
C.	length 27 cm, breadth 27 cm, height 48 cm
D.	length 220 cm, breadth 25 cm, height 40 cm
Answer» C. length 27 cm, breadth 27 cm, height 48 cm

65.	Ratio of permissible stress in direct compression and bending compression is
A.	less than 1
B.	between 1 and 1.5
C.	between 1.5 and 2.0
D.	greater than 2
Answer» A. less than 1

66.	Concrete containing
A.	siliceous aggregates, has higher co-efficient of expansion
B.	igneous aggregates, has intermediate coefficient of expansion
C.	lime stones, has lowest co-efficient of expansion
D.	all the above
Answer» D. all the above

67.	The lower water cement ratio in concrete, introduces
A.	smaller creep and shrinkage
B.	greater density and smaller permeability
C.	improved frost resistance
D.	all the above
Answer» D. all the above

68.	In T-shaped R C. retaining walls, the main reinforcement in the stem is provided on
A.	the front face in one direction
B.	the front face in both directions
C.	the inner face in one direction
D.	the inner face in both directions
Answer» C. the inner face in one direction

69.	The aggregate containing moisture in pores and having its surface dry, is known as
A.	moist aggregates
B.	very dry aggregates
C.	dry aggregates
D.	saturated surface dry aggregate
Answer» D. saturated surface dry aggregate

70.	Pick up the correct statement from the following:
A.	construction joints in columns are provided a few cm below the junction of beam
B.	construction joints in columns are provided at the bottom hunching
C.	construction joints in beams and slabs are provided within middle third
D.	all the above
Answer» D. all the above

71.	According to ISI recommendations, the maximum depth of stress block for balanced section of a beam of effective depth d is
A.	0.43 d
B.	0.55 d
C.	0.68 d
D.	0.85 d
Answer» A. 0.43 d

72.	Pick up the correct proportions of chemical ingredients of cement
A.	lime : silica : alumina : iron oxide : 63 : 22 : 6 : 3
B.	silica : lime : alumina : iron oxide : 63 : 22 : 6 : 3
C.	alumina : silica : lime : iron oxide : 63 : 22 : 6 : 3
D.	iron oxide : alumina : silica : lime : 63 : 22 : 6 : 3
Answer» A. lime : silica : alumina : iron oxide : 63 : 22 : 6 : 3

73.	Internal friction between the ingredients of concrete, is decreased by using
A.	less water
B.	fine aggregates
C.	rich mix
D.	more water and coarse aggregates
Answer» D. more water and coarse aggregates

74.	Pick up the correct statement from the following:
A.	the quality of water governs the strength of concrete
B.	10% excess of water reduces the strength of concrete by 15%
C.	30% excess of water reduces the strength of concrete by 50%
D.	all the above
Answer» D. all the above

75.	Pick up the correct statement from the following:
A.	lime in excess, causes the cement to expand and disintegrate
B.	silica in excess, causes the cement to set slowly
C.	alumina in excess, reduces the strength of the cement
D.	all the above
Answer» D. all the above

76.	If the effective plan area of a warehouse is 54 sq. m, and maximum height of piles permitted is 270 cm, the number of cement bags to be stored, is
A.	2000 bags
B.	2200 bags
C.	2400 bags
D.	2700 bags
Answer» D. 2700 bags

77.	The property of fresh concrete, in which the water in the mix tends to rise to the surface while placing and compacting, is called
A.	segregation
B.	bleeding
C.	bulking
D.	creep
Answer» B. bleeding

78.	Workability of concrete for a given water content is good if the aggregates, are
A.	rounded aggregate
B.	irregular aggregate
C.	angular aggregate
D.	flaky aggregates
Answer» A. rounded aggregate

79.	For preparing ordinary concrete, the quantity of water used, is
A.	5% by weight of aggregates plus 20% of weight of cement
B.	10% by weight of aggregates plus 10% of weight of cement
C.	5% by weight of aggregates plus 30% of weight of cement
D.	30% by weight of aggregates plus 10% of weight of cement
Answer» C. 5% by weight of aggregates plus 30% of weight of cement

80.	Finer grinding of cement
A.	affects only the early development of strength
B.	affects only the ultimate strength
C.	both (a) and (b)
D.	does not affect the strength
Answer» A. affects only the early development of strength

81.	The light weight aggregates are obtained from
A.	sedimentary rocks
B.	metamorphic rocks
C.	igneous rocks
D.	volcanic source
Answer» D. volcanic source

82.	The aggregate impact value of the aggregate used in
A.	building concrete is less than 45
B.	road pavement concrete is less than 30
C.	runway concrete is less than 30
D.	all the above
Answer» D. all the above

83.	For walls, columns and vertical faces of all structural members, the form work is generally removed after
A.	24 to 48 hours
B.	3 days
C.	7 days
D.	14 days
Answer» A. 24 to 48 hours

84.	Efflorescence in cement is caused due to an excess of
A.	alumina
B.	iron oxide
C.	silica
D.	alkalis
Answer» D. alkalis

85.	For given workability the grading requiring the least amount of water is one that gives
A.	greatest surface area for the given cement and aggregates
B.	least surface area for the given cement and aggregates
C.	least weight for the given cement and aggregates
D.	greatest weight for the given cement and aggregates
Answer» A. greatest surface area for the given cement and aggregates

86.	Minimum pitch of transverse reinforcement in a column is
A.	the least lateral dimension of the member
B.	sixteen times the smallest diameter of longitudinal reinforcement bar to be tied
C.	forty-eight times the diameter of transverse reinforcement
D.	lesser of the above three values
Answer» D. lesser of the above three values

87.	Pick up the incorrect statement applicable to the field test of good cement.
A.	when one thrusts one\s hand into a bag of cement, one should feel warm
B.	the colour of the cement is bluish
C.	by rubbing cement in between fingers, one should feed rough
D.	all the above
Answer» D. all the above

88.	An aggregate is known as cyclopean aggregate if its size is more than
A.	4.75 mm
B.	30 mm
C.	60 mm
D.	75 mm
Answer» D. 75 mm

89.	Workability of concrete mix with low water cement ratio is determined by
A.	tensile strength test
B.	slump test
C.	compaction factor test
D.	flexural strength test
Answer» C. compaction factor test

90.	The effect of creep on modular ratio is
A.	to decrease it
B.	to increase it
C.	either to decrease or to increase it
D.	to keep it unchanged
Answer» B. to increase it

91.	The type of aggregates not suitable for high strength concrete and for pavements subjected to tension, is
A.	rounded aggregate
B.	irregular aggregate
C.	angular aggregate
D.	flaky aggregate
Answer» A. rounded aggregate

92.	The maximum percentage of chemical ingredient of cement is that of
A.	magnesium oxide
B.	iron oxide
C.	silica
D.	lime
Answer» D. lime

93.	The commercial name of white and coloured cement in India, is
A.	colorcrete
B.	silvicrete
C.	snowcem
D.	all the above
Answer» D. all the above

94.	An excess of flaky particles in concrete aggregates
A.	decreases the workability
B.	increases the quantity of water and sand
C.	more than 15% are not desirable
D.	all the above
Answer» D. all the above

95.	Increase in the moisture content in concrete
A.	reduces the strength
B.	increases the strength
C.	does not change the strength
D.	all of the above
Answer» A. reduces the strength

96.	The 28 days cube strength of mass concrete using aggregates of maximum size 5 cm for gravity dams should be
A.	between 150 to 300 kg/cm2
B.	between 350 to 600 kg/cm2
C.	between 150 to 500 kg/cm2
D.	below 200 kg/cm2
Answer» D. below 200 kg/cm2

97.	Select the incorrect statement
A.	lean mixes bleed more as compared to rich ones.
B.	bleeding can be minimized by adding pozzolana finer aggregate
C.	bleeding can be increased by addition \of calcium chloride
D.	none of the above
Answer» D. none of the above

98.	Permissible compressive strength of M 150 concrete grade is
A.	100 kg/cm2
B.	150 kg/cm2
C.	200 kg/cm2
D.	250 kg/cm2
Answer» C. 200 kg/cm2

99.	Cement used for normal concrete construction, is obtained by burning a mixture of
A.	siliceous and argillaceous materials
B.	argillaceous and calcareous materials
C.	siliceous and calcareous materials
D.	siliceous, argillaceous and calcareous materials
Answer» D. siliceous, argillaceous and calcareous materials

100.	As compared to ordinary Portland cement, high alumina cement has
A.	higher initial setting time but lower final setting time
B.	lower initial setting time but higher final setting time
C.	higher initial and final setting times
D.	lower initial and final setting times
Answer» A. higher initial setting time but lower final setting time

101.	The maximum amount of dust which may be permitted in aggregates is
A.	5% of the total aggregates for low workability with a coarse grading
B.	10% of the total aggregates for low workability with a fine grading
C.	20% of the total aggregates for a mix having high workability with fine grading
D.	all the above
Answer» D. all the above

102.	Bulking of sand is
A.	mixing of different sizes of sand particles
B.	mixing of lime with sand
C.	maximum water with sand
D.	swelling of sand when wetted
Answer» D. swelling of sand when wetted

103.	For a longitudinal reinforcing bar in a column, the minimum cover shall neither be less than the diameter of bar nor less than
A.	15 mm
B.	25 mm
C.	30 mm
D.	40 mm
Answer» D. 40 mm

104.	Workability of concrete is measured by
A.	vicat apparatus test
B.	slump test
C.	minimum void method
D.	talbot richard test
Answer» B. slump test

105.	The size of fine aggregates does not exceed
A.	2.75 mm
B.	3.00 mm
C.	3.75 mm
D.	4.75 mm
Answer» D. 4.75 mm

106.	The main reason for providing number of reinforcing bars at a support in a simply supported beam is to resist in that zone
A.	compressive stress
B.	shear stress
C.	bond stress
D.	tensile stress
Answer» C. bond stress

107.	The entrained air in concrete
A.	increases workability
B.	decreases workability
C.	decreases resistance to weathering
D.	increases strength
Answer» A. increases workability

108.	According to IS: 4561978, the flexural strength of concrete is
A.	directly proportional to compressive strength
B.	inversely proportional to compressive strength
C.	directly proportional to square root of compressive strength
D.	inversely proportional to square root of compressive strength
Answer» C. directly proportional to square root of compressive strength

109.	Slump test is done for
A.	clay
B.	sand
C.	lime
D.	concrete
Answer» D. concrete

110.	Di-calcium silicate (C2S)
A.	hydrates rapidly
B.	generates less heat of hydration
C.	hardens rapidly
D.	provides less ultimate strength to cement
Answer» B. generates less heat of hydration

111.	The limits of percentage p of the longitudinal reinforcement in a column is given by
A.	0.15% to 2%
B.	0.8% to 4%
C.	0.8% to 6%
D.	0.8% to 8%
Answer» C. 0.8% to 6%

112.	The risk of segregation is more for
A.	wetter mix
B.	larger proportion of maximum size aggregate
C.	coarser grading
D.	all the above
Answer» D. all the above

113.	Le-Chatelier’s apparatus is used for testing
A.	soundness of cement
B.	hardness of cement
C.	strength of cement
D.	durability of cement
Answer» A. soundness of cement

114.	Construction joints are generally provided in concrete
A.	roads
B.	retaining walls
C.	lining of canals
D.	all the above
Answer» D. all the above

115.	If a grading curve is horizontal between the portions of 20 mm I.S. Sieve and 4.75 mm I.S. Sieve, the graded aggregates do not contain
A.	20 mm particles
B.	10 mm particles
C.	4.75 mm particles
D.	all the above
Answer» D. all the above

116.	Most common method of pre-stressing used for factory production is
A.	long line method
B.	freyssinet system
C.	magnel-blaton system
D.	lee-macall system
Answer» A. long line method

117.	C.R.R.I. charts are used to obtain a relationship between strength of concrete and
A.	water cement ratio
B.	workability
C.	grading of aggregate
D.	fineness modulus
Answer» A. water cement ratio

118.	For the design of retaining walls, the minimum factor of safety against overturning is taken as
A.	1.5
B.	2.0
C.	2.5
D.	3.0
Answer» B. 2.0

119.	If the depth of moist sand in a cylinder is 15 cm and the depth of the sand when fully inundated with water is 12 cm, the bulking of the moist sand, is
A.	10 %
B.	12 %
C.	15 %
D.	25 %
Answer» D. 25 %

120.	If aggregates completely pass through a sieve of size 75 mm and are retained on a sieve of size 60 mm, the particular aggregate will be flaky if its minimum dimension is less than
A.	20.5 mm
B.	30.5 mm
C.	40.5 mm
D.	50.5 mm
Answer» C. 40.5 mm

121.	If the foundations of all the columns of a structure are designed on the total live and dead load basis, then
A.	there will be no settlement of columns
B.	there will be no differential settlement
C.	the settlement of exterior columns will be more than interior columns
D.	the settlement of interior columns will be more than exterior columns
Answer» C. the settlement of exterior columns will be more than interior columns

122.	Saw dust can be rendered chemically inert by boiling it in water containing
A.	ferrous sulphate
B.	potassium chloride
C.	ammonia
D.	nitric acid
Answer» A. ferrous sulphate

123.	A concrete having a slump of 6.5 cm, is said to be
A.	dry
B.	earth moist
C.	semi-plastic
D.	plastic
Answer» D. plastic

124.	To obtain a very high strength concrete, use very fine grained
A.	granite
B.	magnetite
C.	barite
D.	volcanic scoria
Answer» A. granite

125.	Vicat apparatus is used for
A.	fineness test
B.	consistency test
C.	test for setting time
D.	test for tensile strength
Answer» B. consistency test

126.	Which of the following losses of pre-stress occurs only in pre-tensioning and not in posttensioning?
A.	elastic shortening of concrete
B.	shrinkage of concrete
C.	creep of concrete
D.	loss due to friction
Answer» A. elastic shortening of concrete

127.	The type of aggregates of same nominal size, which contain less voids when compacted, are
A.	rounded spherical
B.	irregular
C.	flaky
D.	none of these
Answer» A. rounded spherical

128.	Pre-stress loss due to friction occurs
A.	only in post-tensioned beams
B.	only in pre-tensioned beams
C.	in both post-tensioned and pre-tensioned beams
D.	none of the above
Answer» A. only in post-tensioned beams

129.	Pick up the correct statement from the following:
A.	an increase in water content must be accompanied by an increase in cement content
B.	angular and rough aggregates reduce the workability of the concrete
C.	the slump of the concrete mix decreases due to an increase in temperature
D.	all the above
Answer» D. all the above

130.	In the method of voids for determination of the quantity of cement paste, it is assumed that
A.	voids in coarse aggregates are filled by fine aggregates
B.	voids in fine aggregates are filled by the cement paste
C.	volume of fine aggregates is equal to total voids in coarse aggregates plus 10% extra
D.	all the above
Answer» D. all the above

131.	As compared to ordinary Portland cement, use of pozzolana cement
A.	reduces workability
B.	increases bleeding
C.	increases shrinkage
D.	increases strength
Answer» C. increases shrinkage

132.	The following proportion of the ingredients of concrete mix, is not in conformation to arbitrary method of proportioning
A.	1 : 1 : 2
B.	1 : 2 : 4
C.	1 : 3 : 6
D.	1 : 4 : 10
Answer» D. 1 : 4 : 10

133.	The strength and quality of concrete, depend upon:
A.	grading of aggregates
B.	surface area of aggregates
C.	shape of aggregates
D.	all the above
Answer» D. all the above

134.	The factor of safety for
A.	steel and concrete are same
B.	steel is lower than that for concrete
C.	steel is higher than that for concrete
D.	none of the above
Answer» B. steel is lower than that for concrete

135.	The preliminary test is repeated if the difference of compressive strength of three test specimens, exceeds
A.	5 kg/cm2
B.	8 kg/cm2
C.	10 kg/cm2
D.	15 kg/cm2
Answer» D. 15 kg/cm2

136.	Setting time of cement increases by adding
A.	gypsum
B.	hydrogen peroxide
C.	calcium chloride
D.	sodium oxide
Answer» A. gypsum

137.	According to IS: 4561978, the maximum reinforcement in a column is
A.	2 %
B.	4 %
C.	6 %
D.	8 %
Answer» C. 6 %

138.	According to the recommendations of IS : 456-1978, the expansion joints
A.	are provided where plane changes abruptly
B.	are provided to ensure minimum resistance
C.	do not carry reinforcement across them
D.	all the above
Answer» D. all the above

139.	The impurity of mixing water which affects the setting time and strength of concrete, is
A.	sodium sulphates
B.	sodium chlorides
C.	sodium carbonates and bicarbonates
D.	calcium bicarbonates
Answer» C. sodium carbonates and bicarbonates

140.	If the size of panel in a flat slab is 6 m × 6 m, then as per Indian Standard Code, the widths of column strip and middle strip are
A.	3.0 m and 1.5 m
B.	1.5 m and 3.0 m
C.	3.0 m and 3.0 m
D.	1.5 m and 1.5 m
Answer» C. 3.0 m and 3.0 m

141.	Pick up the incorrect statement from the following:
A.	the bottom and top ends of slump mould are parallel to each other
B.	the axis of the mould is perpendicular to the end faces
C.	the internal surface of the mould is kept clean and free from set cement
D.	the mould is in the form of a frustum of hexagonal pyramid
Answer» D. the mould is in the form of a frustum of hexagonal pyramid

142.	The concrete mix which causes difficulty in obtaining a smooth finish, possess
A.	segregation
B.	internal friction
C.	hardness
D.	bleeding
Answer» C. hardness

143.	While designing the pile as a column, the end conditions are nearly
A.	both ends hinged
B.	both ends fixed
C.	one end fixed and other end hinged
D.	one end fixed and other end free
Answer» C. one end fixed and other end hinged

144.	The internal dimensions of a ware house are 15 m × 5.6 m, and the maximum height of piles is 2.70 m, the maximum number of bags to be stored in two piles, are
A.	1500 bags
B.	2000 bags
C.	2500 bags
D.	3000 bags
Answer» D. 3000 bags

145.	Pick up the incorrect statement from the following. While performing preliminary test on concrete
A.	proportions of the material and water should be the same as to be used at the work site
B.	cement should be mixed by hand in order to maintain uniformity
C.	concrete mix should be stored in air-tight containers
D.	concrete ingredients should be kept at a temperature of 37° ± 2°c
Answer» D. concrete ingredients should be kept at a temperature of 37° ± 2°c

146.	In a spherical dome the hoop stress due to a concentrated load at crown is
A.	compressive everywhere
B.	tensile everywhere
C.	partly compressive and partly tensile
D.	zero
Answer» B. tensile everywhere

147.	I.S. Sieve Nos. 10 mm and 4.75 mm are generally used for grading of
A.	coarse aggregates
B.	fine aggregates
C.	neither (a) nor (b)
D.	both (a) and (b)
Answer» D. both (a) and (b)

148.	Log Angles machine is used to test the aggregate for
A.	crushing strength
B.	impact value
C.	abrasion resistance
D.	water absorption
Answer» C. abrasion resistance

149.	The property of the ingredients to separate from each other while placing the concrete is called
A.	segregation
B.	compaction
C.	shrinkage
D.	bulking
Answer» A. segregation

150.	Pick up the correct statement from the following:
A.	higher workability indicates unexpected increase in the moisture content
B.	higher workability indicates deficiency of sand
C.	if the concrete mix is dry, the slump is zero
D.	all the above
Answer» D. all the above

151.	The process of mixing, transporting, placing and compacting concrete using Ordinary Port land Cement should not take more than
A.	30 minutes
B.	40 minutes
C.	60 minutes
D.	90 minutes
Answer» A. 30 minutes

152.	The strength of concrete after one year as compared to 28 days strength is about
A.	10 to 15% more
B.	15 to 20% more
C.	20 to 25% more
D.	25 to 50% more
Answer» C. 20 to 25% more

153.	Specified compressive strength of concrete is obtained from cube tests at the end of
A.	3 days
B.	7 days
C.	21 days
D.	28 days
Answer» D. 28 days

154.	Pick up the incorrect statement from the following:
A.	tricalcium silicate (c3s) hydrates rapidly
B.	tricalcium silicate (c3s) generates more heat of hydration
C.	tricalcium silicate (c3s) develops early strength
D.	tricalcium silicate (c3s) has more resistance to sulphate attack
Answer» D. tricalcium silicate (c3s) has more resistance to sulphate attack

155.	If the permissible stress in steel in tension is 140 N/mm², then the depth of neutral axis for a singly reinforced rectangular balanced section will be
A.	0.35 d
B.	0.40 d
C.	0.45 d
D.	dependent on grade of concrete also
Answer» B. 0.40 d

156.	A construction joint is provided where
A.	bending moment is small
B.	shear force is small
C.	the member is supported by other member
D.	all the above
Answer» D. all the above

157.	Sand generally contains salt if it is obtained from:
A.	nala beds
B.	river beds
C.	sea beds
D.	none of these
Answer» C. sea beds

158.	According to IS: 4561978, minimum slenderness ratio for a short column is
A.	less than 12
B.	less than 18
C.	between 18 and 24
D.	more than 24
Answer» A. less than 12

159.	Water cement ratio is
A.	volume of water to that of cement
B.	weight of water to that of cement
C.	weight of concrete to that of water
D.	both (a) and (b) of the above
Answer» D. both (a) and (b) of the above

160.	For a concrete mix 1:3:6 and water cement ratio 0.6 both by weight, the quantity of water required per bag, is
A.	10 kg
B.	12 kg
C.	14 kg
D.	16 kg
Answer» C. 14 kg

161.	is the span)
A.	l/3
B.	l/5
C.	l/7
D.	l/10
Answer» C. l/7

162.	Pick up the incorrect statement from the following:
A.	in properly graded aggregates, bulk density is more
B.	in single size aggregates, bulk density is least
C.	in single size aggregates, bulk density is maximum
D.	none of these
Answer» C. in single size aggregates, bulk density is maximum

163.	To prevent segregation, the maximum height for placing concrete, is
A.	100 cm
B.	125 cm
C.	150 cm
D.	200 cm
Answer» A. 100 cm

164.	For a simply supported beam of span 15 m, the minimum effective depth to satisfy the vertical deflection limits should be
A.	600 mm
B.	750 mm
C.	900 mm
D.	more than 1 m
Answer» B. 750 mm

165.	For compacting plain concrete road surface of thickness less than 20 cm, we use
A.	internal vibrator
B.	screed vibrator
C.	form vibrator
D.	none of these
Answer» B. screed vibrator

166.	Expansion joints are provided if the length of concrete structures exceeds
A.	10 m
B.	15 m
C.	15 m
D.	45 m
Answer» D. 45 m

167.	The permissible diagonal tensile stress in reinforced brick work is
A.	about 0.1 n/mm²
B.	zero
C.	0.3 n/mm² to 0.7 n/mm²
D.	about 1.0 n/mm²
Answer» A. about 0.1 n/mm²

168.	Pick up the correct statement from the following:
A.	the concrete gains strength due to hydration of cement
B.	the concrete does not set at freezing point
C.	the strength of concrete increases with its age
D.	all the above
Answer» D. all the above

169.	Separation of water or water sand cement from a freshly concrete, is known
A.	bleeding
B.	creeping
C.	segregation
D.	flooding
Answer» A. bleeding

170.	The critical section for finding maximum bending moment for footing under masonry wall is located
A.	at the middle of the wall
B.	at the edge of the wall
C.	halfway between the middle and edge of the wall
D.	at a distance equal to effective depth of footing from the edge of the wall
Answer» C. halfway between the middle and edge of the wall

171.	On a grading curve, the gap grading is represented by
A.	a horizontal line
B.	a vertical line
C.	n.w. inclined line
D.	n.e. inclined line
Answer» A. a horizontal line

172.	High temperature
A.	increases the strength of concrete
B.	decreases the strength of concrete
C.	has no effect on the strength of concrete
D.	none of these
Answer» B. decreases the strength of concrete

173.	Horizontal construction joints in concrete walls are generally provided at
A.	soffit level
B.	window sill level
C.	floor level
D.	all the above
Answer» D. all the above

174.	Stress strain curve of high tensile steel
A.	has a definite yield point
B.	does not show definite yield point but yield point is defined by 0.1% proof stress
C.	does not show definite yield point but yield point is defined by 0.2% proof stress
D.	does not show definite yield point but yield point is defined by 2% proof stress,
Answer» C. does not show definite yield point but yield point is defined by 0.2% proof stress

175.	Addition of pozzolana to cement causes
A.	reduction in permeability
B.	loss of heat of hydration
C.	reduction in bleeding
D.	all the above
Answer» D. all the above

176.	Permissible compressive strength of M 200 concrete grade is
A.	100 kg/cm2
B.	150 kg/cm2
C.	200 kg/cm2
D.	250 kg/cm2
Answer» C. 200 kg/cm2

177.	The minimum diameter of longitudinal bars in a column is
A.	6 mm
B.	8 mm
C.	12 mm
D.	16 mm
Answer» C. 12 mm

178.	The high strength of rapid hardening cement at early stage, is due to its
A.	finer grinding
B.	burning at high temperature
C.	increased lime cement
D.	higher content of tricalcium
Answer» C. increased lime cement

179.	Sand requiring a high water cement ratio, belongs to
A.	zone i
B.	zone ii
C.	zone iii
D.	zone iv
Answer» A. zone i

180.	Minimum grade of concrete to be used in reinforced concrete as per IS: 4561978 is
A.	m 15
B.	m 20
C.	m 10
D.	m 25
Answer» A. m 15

181.	While compacting the concrete by a mechanical vibrator, the slump should not exceed
A.	2.5 cm
B.	5.0 cm
C.	7.5 cm
D.	10 cm
Answer» B. 5.0 cm

182.	Non-uniform compaction may cause the concrete
A.	porous
B.	non-homogeneous
C.	reduced strength
D.	all the above
Answer» D. all the above

183.	Modulus of rupture of concrete is a measure of
A.	flexural tensile strength
B.	direct tensile strength
C.	compressive strength
D.	split tensile strength
Answer» A. flexural tensile strength

184.	M10 grade of concrete approximates
A.	1 : 3 : 6 mix
B.	1 : 1 : 2 mix
C.	1 : 2 : 4 mix
D.	1 : 1.5 : 3 mix
Answer» A. 1 : 3 : 6 mix

185.	Higher workability of concrete is required if the structure is
A.	made with cement concrete
B.	thick and reinforced
C.	thin and heavily reinforced
D.	thick and heavily reinforced
Answer» D. thick and heavily reinforced

186.	For a cantilever of effective depth of 0.5 m, the maximum span to satisfy vertical deflection limit is
A.	3.5 m
B.	4 m
C.	4.5 m
D.	5 m
Answer» A. 3.5 m

187.	The bulk density of aggregates does not depend upon:
A.	size and shape of aggregates
B.	specific gravity of aggregates
C.	grading of aggregates
D.	size and shape of the container
Answer» D. size and shape of the container

188.	How long will it take for the concrete to achieve 100% of its strength?
A.	7 days
B.	14 days
C.	21 days
D.	28 days
Answer» D. 28 days

189.	A higher modular ratio shows
A.	higher compressive strength of concrete
B.	lower compressive strength of concrete
C.	higher tensile strength of steel
D.	lower tensile strength of steel
Answer» B. lower compressive strength of concrete

190.	For the construction of cement concrete floor, the maximum permissible size of aggregate, is
A.	4 mm
B.	6 mm
C.	8 mm
D.	10 mm
Answer» D. 10 mm

191.	The specifications of a cement bag for storage, are
A.	weight 50 kg
B.	height 18 cm
C.	plan area 3000 sq. cm
D.	all the above
Answer» D. all the above

192.	The main reinforcement in the heel of a T-shaped R.C. retaining wall is provided on
A.	top face perpendicular to wall
B.	bottom face perpendicular to wall
C.	both top and bottom faces perpendicular to wall
D.	none of the above
Answer» A. top face perpendicular to wall

193.	Separation of coarse aggregates from mortar during transportation, is known
A.	bleeding
B.	creeping
C.	segregation
D.	shrinkage
Answer» C. segregation

194.	A flaky aggregate is said to be elongated if its length is
A.	equal to the mean size
B.	twice the mean size
C.	thrice the mean size
D.	four times the mean size
Answer» B. twice the mean size

195.	You are asked to construct a massive dam, the type of cement you will use, is
A.	ordinary portland cement
B.	rapid hardening cement
C.	low heat cement
D.	blast furnace slag cement
Answer» C. low heat cement

196.	An ideal ware house, is provided
A.	water proof masonry walls
B.	water proof roof
C.	few windows which remain generally closed
D.	all the above
Answer» D. all the above

197.	Normally pre-stressing wires are arranged in the
A.	upper part of the beam
B.	lower part of the beam
C.	center
D.	anywhere
Answer» B. lower part of the beam

198.	Pick up the correct statement from the following:
A.	bulking of sand is caused due to formation of a thin film of surface moisture
B.	fine sand bulks more than coarse sand
C.	the volume of fully saturated sand, is equal to the volume of dry and loose sand
D.	all the above
Answer» D. all the above

199.	The minimum percentage of chemical ingredient of cement is that of
A.	magnesium oxide
B.	iron oxide
C.	alumina
D.	lime
Answer» A. magnesium oxide

200.	Poisson’s ratio for concrete
A.	remains constant
B.	increases with richer mixes
C.	decreases with richer mixes
D.	none of the above
Answer» B. increases with richer mixes

201.	Shrinkage in concrete can be reduced by using
A.	low water cement ratio
B.	less cement in the concrete
C.	proper concrete mix
D.	all the above
Answer» D. all the above

202.	The shuttering of a hall measuring 4 m × 5 m, can be removed after
A.	5 days
B.	7 days
C.	10 days
D.	14 days
Answer» B. 7 days

203.	The approximate value of the ratio between direct tensile strength and flexural strength is
A.	0.33
B.	0.5
C.	0.75
D.	1.0
Answer» B. 0.5

204.	An aggregate is said to be flaky if its least dimension is less than
A.	1/5th of mean dimension
B.	2/5th of mean dimension
C.	3/5th of mean dimension
D.	4/5th of mean dimension
Answer» C. 3/5th of mean dimension

205.	Workability improved by adding
A.	fly ash
B.	hydrated lime
C.	calcium chloride
D.	all the above
Answer» D. all the above

206.	Workability of concrete is inversely proportional to
A.	time of transit
B.	water-cement ratio
C.	the air in the mix
D.	size of aggregate
Answer» A. time of transit

207.	Inert material of a cement concrete mix, is
A.	water
B.	cement
C.	aggregate
D.	none of these
Answer» C. aggregate

208.	If a beam fails in bond, then its bond strength can be increased most economically by
A.	increasing the depth of beam
B.	using thinner bars but more in number
C.	using thicker bars but less in number
D.	providing vertical stirrups
Answer» B. using thinner bars but more in number

209.	Pick up the incorrect statement from the following:
A.	a rich mix of concrete possesses higher strength than that a lean mix of desired workability with excessive quantity of water
B.	the strength of concrete decreases as the water cement ratio increases
C.	good compaction by mechanical vibrations, increases the strength of concrete
D.	none of these
Answer» A. a rich mix of concrete possesses higher strength than that a lean mix of desired workability with excessive quantity of water

210.	Ordinary Portland cement is manufactured from
A.	lime stone and clay
B.	gypsum and lime
C.	pozzolana
D.	lime, pozzolana and clay
Answer» B. gypsum and lime

211.	The percentage of reinforcement in case of slabs, when high strength deformed bars are used is not less than
A.	0.15
B.	0.12
C.	0.30
D.	1.00
Answer» B. 0.12

212.	Addition of pozzolana to cement
A.	decreases workability
B.	increases strength
C.	increases heat of hydration
D.	none of these
Answer» D. none of these

213.	If 50 kg of fine aggregates and 100 kg of coarse aggregates are mixed in a concrete whose water cement ratio is 0.6, the weight of water required for harsh mix, is
A.	8 kg
B.	10 kg
C.	12 kg
D.	14 kg
Answer» C. 12 kg

214.	The minimum cover to the ties or spirals should not be less than
A.	15 mm
B.	20 mm
C.	25 mm
D.	50 mm
Answer» C. 25 mm

215.	According to Water-Cement Ratio Law, the strength of workable plastic concrete
A.	depends upon the amount of water used in the mix
B.	does not depend upon the quality of cement mixed with aggregates
C.	does not depend upon the quantity of cement mixed with aggregates
D.	all the above
Answer» D. all the above

216.	Sands of zone I are:
A.	course
B.	medium
C.	medium to fine
D.	fine
Answer» A. course

217.	According to Whitney’s theory, ultimate strain of concrete is assumed to be
A.	0.03 %
B.	0.1 %
C.	0.3 %
D.	3 %
Answer» C. 0.3 %

218.	The condition not applicable to water cement ratio law, is
A.	internal moisture conditions on hydration continue till complete strength is gained
B.	concrete specimens may be tested at any temperature
C.	concrete specimens need be of same age
D.	concrete specimens need be of same size
Answer» B. concrete specimens may be tested at any temperature

219.	If the slump of a concrete mix is 60 mm, its workability is
A.	very low
B.	low
C.	medium
D.	high
Answer» C. medium

220.	Cube strength of controlled concrete to be used for pre-tensioned and post-tensioned work respectively should not be less than
A.	35 mpa and 42 mpa
B.	42 mpa and 35 mpa
C.	42 mpa and 53 mpa
D.	53 mpa and 42 mpa
Answer» B. 42 mpa and 35 mpa

221.	The void ratio of
A.	single size coarse aggregate is roughly 0.45
B.	graded coarse aggregate is roughly 0.040
C.	fine aggregate is roughly 0.45
D.	all the above
Answer» D. all the above

222.	According to IS : 382-1963, a good aggregate should be
A.	chemically inert
B.	sufficiently strong
C.	hard and durable
D.	all the above
Answer» D. all the above

223.	The compressive strength of 100 mm cube as compared to 150 mm cube is always
A.	less
B.	more
C.	equal
D.	none of the above
Answer» B. more

224.	The diameter of the Vicat plunger is 10 mm and its length varies from
A.	20 mm to 30 mm
B.	30 mm to 40 mm
C.	40 mm to 50 mm
D.	50 mm to 60 mm
Answer» C. 40 mm to 50 mm

225.	Gypsum is added for
A.	colour
B.	strength
C.	controlling setting time
D.	none of these
Answer» C. controlling setting time

226.	Modulus of elasticity of steel as per IS: 4561978 shall be taken as
A.	20 kn/cm²
B.	200 kn/cm²
C.	200 kn/mm²
D.	2 × 106 n/cm²
Answer» C. 200 kn/mm²

227.	The grade of concrete M 150 means that compressive strength of a 15 cm cube after 28 days, is
A.	100 kg/cm2
B.	150 kg/cm2
C.	200 kg/cm2
D.	250 kg/cm2
Answer» B. 150 kg/cm2

228.	The cement becomes useless if its absorbed moisture content exceeds
A.	1 %
B.	2 %
C.	3 %
D.	5 %
Answer» D. 5 %

229.	In reinforced concrete footing on soil, the minimum thickness at edge should not be less than
A.	100 mm
B.	150 mm
C.	200 mm
D.	250 mm
Answer» B. 150 mm

230.	For preparing a test-specimen, it is necessary
A.	to mix cement and fine aggregate by dry hand
B.	to mix coarse aggregates
C.	to mix water to the cement, fine aggregates and coarse aggregates
D.	all the above
Answer» D. all the above

231.	For a good concrete
A.	aggregates should be hard and durable
B.	water should be free from organic materials
C.	cement should be sufficient to produce the required strength
D.	all the above
Answer» D. all the above

232.	The process of hardening the concrete by keeping its surface moist is known
A.	placing
B.	wetting
C.	curing
D.	compacting
Answer» C. curing

233.	For the construction of the retaining structures, the type of concrete mix to be used, is
A.	1 : 3 : 6
B.	1 : 2 : 4
C.	1 : 1½ : 3
D.	1 : 4 : 8
Answer» C. 1 : 1½ : 3

234.	The produce impermeable concrete
A.	thorough mixing of concrete is required
B.	proper compaction of concrete is required
C.	proper curing of concrete is required
D.	all the above
Answer» D. all the above

235.	Pozzolanic properties exist in
A.	shales
B.	fly ash
C.	pumicite
D.	all the above
Answer» D. all the above

236.	A continuous beam is deemed to be a deep beam when the ratio of effective span to overall depth (1/D) is less than
A.	1.5
B.	2.0
C.	2.5
D.	3.0
Answer» C. 2.5

237.	Pick up the correct statement from the following:
A.	the weight of ingredients of concrete mix, is taken in kilograms
B.	water and aggregates are measured in litres
C.	20 bags of cement make one tonne
D.	all the above
Answer» D. all the above

238.	If fineness modulus of sand is 2.5, it is graded as
A.	very fine sand
B.	fine sand
C.	medium sand
D.	coarse sand
Answer» B. fine sand

239.	Maximum quantity of water needed per 50 kg of cement for M 15 grade of concrete is
A.	28 liters
B.	30 liters
C.	32 liters
D.	34 liters
Answer» C. 32 liters

240.	The increased cohesiveness of concrete, makes it
A.	less liable to segregation
B.	more liable to segregation
C.	more liable to bleeding
D.	more liable for surface scaling in frosty weather
Answer» A. less liable to segregation

241.	Concrete is unsuitable for compaction by a vibrator if it is
A.	dry
B.	earth moist
C.	semi-plastic
D.	plastic
Answer» D. plastic

242.	In order to obtain the best workability of concrete, the preferred shape of aggregate is
A.	rounded
B.	elongated
C.	angular
D.	all of the above
Answer» A. rounded

243.	Hydration of cement is due to chemical action of water with
A.	tricalcium silicate and dicalcium silicate
B.	dicalcium silicate and tricalcium aluminate
C.	tricalcium aluminate and tricalcium alumino ferrite
D.	all the above
Answer» D. all the above

244.	An aggregate which passes through 25 mm I.S. sieve and is retained on 20 mm sieve, is said to be flaky if its least dimension is less than
A.	22.5 mm
B.	18.5 mm
C.	16.5 mm
D.	13.5 mm
Answer» D. 13.5 mm

245.	Approximate value of shrinkage strain in concrete, is
A.	0.003
B.	0.0003
C.	0.00003
D.	0.03
Answer» B. 0.0003

246.	For quality control of Portland cement, the test essentially done is
A.	setting time
B.	tensile strength
C.	consistency
D.	all the above
Answer» D. all the above

247.	Strength of concrete with passage of time
A.	increases
B.	decreases
C.	fluctuates
D.	remains constant
Answer» A. increases

248.	Which of the following statements is incorrect?
A.	higher vee-bee time shows lower workability
B.	higher slump shows higher workability
C.	higher compacting factor shows higher workability
D.	none of the above
Answer» D. none of the above

249.	To obtain cement dry powder, lime stones and shales or their slurry, is burnt in a rotary kiln at a temperature between
A.	1100° and 1200°c
B.	1200° and 1300°c
C.	1300° and 1400°c
D.	1400° and 1500°c
Answer» D. 1400° and 1500°c

250.	In a pile of length , the points of suspension from ends for lifting it are located at
A.	0.207 l
B.	0.25 l
C.	0.293 l
D.	0.333 l
Answer» A. 0.207 l

251.	Curing a concrete for long period ensures better
A.	volume stability
B.	strength
C.	water resistance
D.	all the above
Answer» D. all the above

252.	Batching error means inaccuracy in the quantity of
A.	aggregates
B.	cement
C.	water
D.	all the above
Answer» D. all the above

253.	If the storey height is equal to length of RCC wall, the percentage increase in strength is
A.	0
B.	10
C.	20
D.	30
Answer» B. 10

254.	If X, Y and Z are the fineness modulli of coarse, fine and combined aggregates, the percentage (P) of fine aggregates to combined aggregates, is
A.	p = [(z – x)/(z – y)] × 100
B.	p = [(x – z)/(z – y)] × 100
C.	p = [(x – z)/(z + y)] × 100
D.	p = [(z + x)/(z – y)] × 100
Answer» B. p = [(x – z)/(z – y)] × 100

255.	If the depth of actual neutral axis in a beam is more than the depth of critical neutral axis, then the beam is called
A.	balanced beam
B.	under-reinforced beam
C.	over-reinforced beam
D.	none of the above
Answer» C. over-reinforced beam

256.	Proper proportioning of concrete, ensures
A.	desired strength and workability
B.	desired durability
C.	water tightness of the structure
D.	all the above
Answer» D. all the above

257.	The relation between modulus of rupture fcr, splitting strength fcs and direct tensile strength fcl is given by
A.	fcr – fcs = fcl
B.	fcr > fcs > fcl
C.	fcr < fcs < fcl
D.	fcs > fcr > fcl
Answer» B. fcr > fcs > fcl

258.	Air entrainment in the concrete increases
A.	workability
B.	strength
C.	the effects of temperature variations
D.	the unit weight
Answer» A. workability

259.	Construction joints are provided
A.	where b.m. and s.f. are small
B.	where the member is supported by other member
C.	at 18 m apart in huge structures
D.	all the above
Answer» D. all the above

260.	Maximum distance between expansion joints in structures as per IS: 456 1978 is
A.	20 m
B.	30 m
C.	45 m
D.	60 m
Answer» C. 45 m

261.	Ordinary concrete is not used for concrete grade
A.	m 100
B.	m 150
C.	m 250
D.	m 400
Answer» D. m 400

262.	In a spherical dome subjected to concentrated load at crown or uniformly distributed load, the meridional force is always
A.	zero
B.	tensile
C.	compressive
D.	tensile or compressive
Answer» C. compressive

263.	An aggregate is said to be flaky, if its least dimension is less than
A.	2/3 mean dimension
B.	3/4 mean dimension
C.	3/5 mean dimension
D.	5/8 mean dimension
Answer» C. 3/5 mean dimension

264.	While designing an air entrained concrete
A.	water cement ratio is reduced
B.	proportion of aggregates is reduced
C.	an allowance for the entrained air is made
D.	all the above
Answer» D. all the above

265.	Minimum thickness of load bearing RCC wall should be
A.	50 mm
B.	100 mm
C.	150 mm
D.	200 mm
Answer» B. 100 mm

266.	M 150 grade of concrete approximates
A.	1 : 3 : 6 mix
B.	1 : 1 :2 mix
C.	1 : 2 : 4 mix
D.	1 : 1.5 : 3 mix
Answer» B. 1 : 1 :2 mix

267.	Permissible compressive strength of M 300 concrete grade is
A.	100 kg/cm2
B.	150 kg/cm2
C.	200 kg/cm2
D.	300 kg/cm2
Answer» D. 300 kg/cm2

268.	Strength of concrete increases with
A.	increase in water-cement ratio
B.	increase in fineness of cement
C.	decrease in curing time
D.	decrease in size of aggregate
Answer» B. increase in fineness of cement

269.	For ensuring quality of concrete, use
A.	single sized aggregates
B.	two sized aggregate
C.	graded aggregates
D.	coarse aggregates
Answer» C. graded aggregates

270.	In working stress design, permissible bond stress in the case of deformed bars is more than that in plain bars by
A.	10 %
B.	20 %
C.	30 %
D.	40 %
Answer» D. 40 %

271.	Workability improved by adding
A.	air-entraining agent
B.	foaming agent
C.	oily-agent
D.	all the above
Answer» D. all the above

272.	The rock which is not calcareous, is:
A.	lime stone
B.	chalk
C.	laterite
D.	none of these
Answer» D. none of these

273.	A T-shaped retaining wall mainly consists of
A.	one cantilever
B.	two cantilevers
C.	three cantilevers
D.	four cantilevers
Answer» C. three cantilevers

274.	Pick up the correct statement from the following:
A.	insufficient quantity of water makes the concrete mix harsh
B.	insufficient quantity of water makes the concrete unworkable
C.	excess quantity of water makes the concrete segregated
D.	all the above
Answer» D. all the above

275.	The fineness modulus of fine aggregate is in the range of
A.	2.0 to 3.5
B.	3.5 to 5.0
C.	5.0 to 7.0
D.	6.0 to 8.5
Answer» A. 2.0 to 3.5

276.	After casting, an ordinary cement concrete on drying
A.	expands
B.	mix
C.	shrinks
D.	none of these
Answer» C. shrinks

277.	The most commonly used admixture which prolongs the setting and hardening time is
A.	gypsum
B.	calcium chloride
C.	sodium silicate
D.	all of the above
Answer» A. gypsum

278.	For given water content, workability decreases if the concrete aggregates contain an excess of
A.	thin particles
B.	flat particles
C.	elongated particles
D.	all the above
Answer» D. all the above

279.	The process of proper and accurate measurement of concrete ingredients for uniformity of proportion, is known
A.	grading
B.	curing
C.	mixing
D.	batching
Answer» D. batching

280.	The load factors for live load and dead load are taken respectively as
A.	1.5 and 2.2
B.	2.2 and 1.5
C.	1.5 and 1.5
D.	2.2 and 2.2
Answer» B. 2.2 and 1.5

281.	The mixture of different ingredients of cement, is burnt at
A.	1000°c
B.	1200°c
C.	1400°c
D.	1600°c
Answer» C. 1400°c

282.	In case of hand mixing of concrete, the extra cement to be added is
A.	5 %
B.	10 %
C.	15 %
D.	20 %
Answer» B. 10 %

283.	If 1500 g of water is required to have a cement paste 1875 g of normal consistency, the percentage of water is,
A.	20 %
B.	25 %
C.	30 %
D.	35 %
Answer» B. 25 %

284.	The percentage of voids in cement is approximately
A.	25 %
B.	40 %
C.	60 %
D.	80 %
Answer» B. 40 %

285.	Water required per bag of cement, is
A.	7 kg
B.	14 kg
C.	21 kg
D.	35 kg
Answer» D. 35 kg

286.	The recommended value of modular ratio for reinforced brick work is
A.	18
B.	30
C.	40
D.	58
Answer» C. 40

287.	For an ordinary Portland cement
A.	residual does not exceed 10% when sieved through is sieve no. 9
B.	soundness varies from 5 to 10 mm
C.	initial setting time is not less than 30 minutes
D.	compressive stress after 7 days, is not less than 175 kg/cm2
Answer» C. initial setting time is not less than 30 minutes

288.	The ratio of the diameter of reinforcing bars and the slab thickness is
A.	1/4
B.	1/5
C.	1/6
D.	1/8
Answer» D. 1/8

289.	Pozzolana cement is used with confidence for construction of
A.	dams
B.	massive foundations
C.	r.c.c. structures
D.	all the above
Answer» D. all the above

290.	Pick up the correct statement from the following:
A.	calcium chloride acts as a retarder
B.	calcium chloride acts as an accelerator
C.	gypsum (calcium sulphate) acts as a retarder
D.	both (b) and (c)
Answer» D. both (b) and (c)

291.	The operation of removing humps and hollows of uniform concrete surface, is known as
A.	floating
B.	screeding
C.	trowelling
D.	finishing
Answer» B. screeding

292.	1% of voids in a concrete mix would reduce its strength by about
A.	5 %
B.	10 %
C.	15 %
D.	20 %
Answer» A. 5 %

293.	For a continuous slab of 3 m × 3.5 m size, the minimum overall depth of slab to satisfy vertical deflection limits is
A.	50 mm
B.	75 mm
C.	100 mm
D.	120 mm
Answer» B. 75 mm

294.	The most useless aggregate is one whose surface texture is
A.	smooth
B.	granular
C.	glassy
D.	honey combed and porous
Answer» C. glassy

295.	The shrinkage of concrete
A.	is proportional to water content is the mix
B.	is proportional to cement concrete
C.	increases with age of concrete
D.	all the above
Answer» D. all the above

296.	The maximum thickness of concrete floor of a cement warehouse, is
A.	10 cm
B.	15 cm
C.	20 cm
D.	25 cm
Answer» D. 25 cm

297.	Too wet concrete may cause
A.	weakness of concrete
B.	excessive laitance
C.	segregation
D.	all the above
Answer» D. all the above

298.	Maximum percentage reinforcement in case of slabs is limited to
A.	2
B.	4
C.	6
D.	8
Answer» B. 4

299.	The commonly used material in the manufacture of cement is
A.	sand stone
B.	slate
C.	lime stone
D.	graphite
Answer» C. lime stone

300.	According to I.S. : 456, the number of grades of concrete mixes, is
A.	3
B.	4
C.	5
D.	7
Answer» D. 7

301.	Grading of sand causes great variation in
A.	workability of concrete
B.	strength of concrete
C.	durability of concrete
D.	all the above
Answer» D. all the above

302.	The percentage of the aggregate of F.M. 2.6 to be combined with coarse aggregate of F.M. 6.8 for obtaining the aggregates of F.M. 5.4, is
A.	30 %
B.	40 %
C.	50 %
D.	60 %
Answer» C. 50 %

303.	The ratio of various ingredients (cement, sand, aggregates) in concrete of grade M 200, is
A.	1 : 2 : 4
B.	1 : 3 : 6
C.	1 : 1½ : 3
D.	1 : 1 : 2
Answer» C. 1 : 1½ : 3

304.	Joints in concrete structures, are provided
A.	to reduce the tensile stresses likely to be developed due to evaporation of water
B.	to minimise the change in the dimensions of the slab
C.	to minimise the necessary cracking
D.	all the above
Answer» D. all the above

305.	For the construction of R.C.C. slabs, columns, beams, walls, etc. the grade of concrete mix used, is
A.	1 : 3 : 6
B.	1 : 1½ : 3
C.	1 : 2 : 4
D.	1 : 1 : 2
Answer» C. 1 : 2 : 4

306.	Pick up the correct statement from the following:
A.	water enables chemical reaction to take place with cement
B.	water lubricates the mixture of gravel, sand and cement
C.	strength of concrete structure largely depends upon its workability
D.	all the above
Answer» D. all the above

307.	The final operation of finishing floors, is known as
A.	screeding
B.	floating
C.	trowelling
D.	finishing
Answer» C. trowelling

308.	Transport of concrete by pumps, is done for a distance of
A.	100 m
B.	200 m
C.	300 m
D.	400 m
Answer» D. 400 m

309.	Curing
A.	reduces the shrinkage of concrete
B.	preserves the properties of concrete
C.	prevents the loss of water by evaporation
D.	all of the above
Answer» D. all of the above

310.	The datum temperature for maturity by Plowman, is
A.	23°c
B.	0°
C.	– 5.6°c
D.	– 11.7°c
Answer» D. – 11.7°c

311.	The bulk density of aggregates, is generally expressed as
A.	tonnes/cubic metre
B.	kg/cubic metre
C.	kg/litre
D.	g/cm3
Answer» C. kg/litre

312.	For concreting tunnel linings, transportation of concrete is done by
A.	pans
B.	wheel borrows
C.	containers
D.	pumps
Answer» D. pumps

313.	The factor which affects workability, is
A.	water content and its temperature
B.	shape and size of the aggregates
C.	air entraining agents
D.	all the above
Answer» D. all the above

314.	Proper batching ensures
A.	economy
B.	durability
C.	workability
D.	all the above
Answer» D. all the above

315.	The ratio of the length to breadth of a wooden float, is
A.	4.5
B.	5.5
C.	6.5
D.	7.5
Answer» D. 7.5

316.	Vicat’s apparatus is used for
A.	fineness test
B.	consistency test
C.	setting time test
D.	soundness test
Answer» B. consistency test

317.	Percentage of pozzolanic material containing clay upto 80% used for the manufacture of pozzolana cement, is
A.	30 %
B.	40 %
C.	50 %
D.	60 %
Answer» A. 30 %

318.	The grade of concrete not recommended by I.S. : 456, is
A.	m 100
B.	m 200
C.	m 300
D.	m 500
Answer» D. m 500

319.	The compaction of concrete, improves
A.	density
B.	strength
C.	durability
D.	all the above
Answer» D. all the above

320.	Segregation is responsible for
A.	honey-combed concrete
B.	porous layers in concrete
C.	surface scaling in concrete
D.	all the above
Answer» D. all the above

321.	Slump test of concrete is a measure of its
A.	consistency
B.	compressive strength
C.	tensile strength
D.	impact value
Answer» A. consistency

322.	If the effective working time is 7 hours and per batch time of concrete is 3 minutes, the output of a concrete mixer of 150 litre capacity, is
A.	15,900 litres
B.	16,900 litres
C.	17,900 litres
D.	18,900 litres
Answer» D. 18,900 litres

323.	An ordinary Portland cement when tested for its fineness, should not leave any residue on I.S. sieve No. 9, more than
A.	5 %
B.	10 %
C.	15 %
D.	20 %
Answer» B. 10 %

324.	The top diameter, bottom diameter and the height of a slump mould are:
A.	10 cm, 20 cm, 30 cm
B.	10 cm, 30 cm, 20 cm
C.	20 cm, 10 cm, 30 cm
D.	20 cm, 30 cm, 10 cm
Answer» A. 10 cm, 20 cm, 30 cm

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