Civil Engineering Competitive Questions
Select the incorrect statement
[ A ] R.C.C has better fire resistance than steel
[ B ] R.C.C. structure is economical than steel structure
[ C ] Strength of concrete decreases as age increases
[ D ] R.C.C can be used for under water and marine structures
Answer : C
3 Water cement ratio is the ratio of
[ A ] Water to cement by weight
[ B ] Water to cement by volume
[ C ] Cement to water by weight
[ D ] Cement to water by volume
Answer : A
4 Concrete is
[ A ] Weak in tension
[ B ] Strong in tension
[ C ] Strong in both tension and compression
[ D ] Weak in compression
Answer : A
5 The entrained air in concrete
[ A ] Increases the strength
[ B ] Decreases the resistance to weathering
[ C ] Increases the workability
[ D ] Decreases the workability
Answer : C
6 Concrete is unsuitable for compaction by vibration if it is
[ A ] Semi – plastic
[ B ] Plastic
[ C ] Earth moist
[ D ] Dry
Answer : B
7 The strength and quality of concrete depends upon
(i)Grading of aggregates
(ii)Shape of aggregates
(iii)Surface area of aggregates
(iv)Surface texture of aggregates
[ A ] i, ii and iv
[ B ] ii, iii and iv
[ C ] i, iii and iv
[ D ] i, ii, iii and iv
Answer : D
8 In order to avoid segregation, fresh concrete should be dropped from a height of
[ A ] Less than one meter
[ B ] Less than two metres
[ C ] More than one metre
[ D ] More than two metres
Answer : A
9 The process of hardening of concrete in the presence of water is called
[ A ] Creep
[ B ] Hydration
[ C ] Shrinkage
[ D ] Curing
Answer : B
10 The process of keeping the concrete structure moist is called
[ A ] Hydration
[ B ] Curing
[ C ] Creep
[ D ] Shrinkage
Answer : B
11 The separation of water or water cement mixture from the freshly laid concrete is known as
[ A ] Workability
[ B ] Segregation
[ C ] Bleeding
[ D ] Creep
Answer : C
12 The continuous strain, which the concrete undergoes due to application of external loads is
called
[ A ] Creep
[ B ] Bleeding
[ C ] Workability
[ D ] Segregation
Answer : A
13 The process of conversion of plastic concrete to solid stage is called
[ A ] Hydration
[ B ] Hardening
[ C ] Setting
[ D ] Curing
Answer : C
14 At 28 days of curing concrete attains a strength of
[ A ] 20 to 25%
[ B ] 60 to 70%
[ C ] 65 to 80%
[ D ] 90 to 95%
Answer : D
15 In a mass concrete, the aggregates occupy a space of
[ A ] 25%
[ B ] 75%
[ C ] 40%
[ D ] 60%
Answer : B
16 The coarse aggregate which possess the property of good interlocking are
[ A ] rounded shape
[ B ] elongated shape
[ C ] angular shape
[ D ] none of the above
Answer : C
17 While placing of concrete the thickness of each layer for R.C.C. is
[ A ] 150 to 300 mm
[ B ] 450 mm
[ C ] 500 to 750 mm
[ D ] 500 mm
Answer : A
18 Increase in water content in a cement concrete
(i) Increases workability
(ii) Increases the strength
[ A ] i
[ B ] ii
[ C ] both (i) and (ii)
[ D ] neither (i) nor (ii)
Answer : A
19 Slump cone test is used to determine
[ A ] Shrinkage of concrete mix
[ B ] Creep of concrete
[ C ] Workability of concrete mix
[ D ] Soundness of concrete
Answer : C
20 While determining the workability of concrete mix, the compaction factor test is ——than the
slump cone test
[ A ] Less accurate
[ B ] More accurate
[ C ] Approximate method
[ D ] None of the above
Answer : B
21 Workability of concrete mix with low water cement ratio is determined by
[ A ] Tensile strength test
[ B ] Slump cone test
[ C ] Compaction factor test
[ D ] Flexural strength test
Answer : C
22 If the slump of a concrete mix is 50 to 100 mm, its workability is
[ A ] Very low
[ B ] Low
[ C ] Medium
[ D ] High
Answer : C
23 A compaction factor of 0.75 indicates ________workability
[ A ] Very low
[ B ] Low
[ C ] Medium
[ D ] High
Answer : A
24 Shrinkage in concrete can be reduced by using
(i) Low water cement ratio (ii) More amount of cement in the concrete
(iii) Presaturated aggregates
[ A ] i
[ B ] i and ii
[ C ] i and iii
[ D ] i, ii and iii
Answer : C
25 The process of proper and accurate measurement of concrete ingredients for uniformity of
proportion, is known as
[ A ] Curing
[ B ] Mixing
[ C ] Grading
[ D ] Batching
Answer : D
26 Select incorrect statement from the following
[ A ] With passage of time, the strength of cement decreases
[ B ] With passage of time, the strength of cement increases
[ 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 : B
27 For compacting plain concrete road surface of thickness less than 20 cm, the following
vibrator is used.
[ A ] Internal vibrator
[ B ] Screed vibrator
[ C ] Form vibrator
[ D ] None of the above
Answer : B
28 Slump test of concrete is a measure of its
[ A ] Consistency
[ B ] Compressive strength
[ C ] Tensile strength
[ D ] Impact value
Answer : A
29 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
30 Minimum grade of concrete for R.C.C. should be _________ , as per IS. 456-2000
[ A ] M10
[ B ] M14
[ C ] M20
[ D ] M25
Answer : C
31 A concrete mass containing 5% of voids
[ A ] Increases its strength by 30%
[ B ] Reduces its strength by 30%
[ C ] Increases its strength by 5%
[ D ] Reduces its strength by 5%
Answer : B
32 Workability of a concrete – mix is determined by
(i)Slump cone test
(ii)Compaction factor test
(iii)Vee bee test
[ A ] i
[ B ] ii
[ C ] i and ii
[ D ] i, ii and iii
Answer : D
33 High strength of concrete requires a water cement ratio of
[ A ] 0.10 to 0.15
[ B ] 0.25 to 0.30
[ C ] 0.45 to 0.60
[ D ] 0.75 to 0.90
Answer : B
34 One bag of cement is equivalent to
[ A ] 50 litres
[ B ] 35 litres
[ C ] 28 litres
[ D ] 14 litres
Answer : B
35 One cubit metre of cement weights
[ A ] 1000 kg
[ B ] 1200 kg
[ C ] 1440 kg
[ D ] 1600 kg
Answer : C
36 As per IS: 456-2000, modulus of elasticity of concrete (in N/mm2) is given by
[ A ] 5700 vfCK
[ B ] 5000 vfCK
[ C ] 3700 vfCK
[ D ] 3000 vfCK
Answer : B
37 In working stress method of design, the factor of safety for concrete and steel respectively
are
[ A ] 3.0 and 1.8
[ B ] 3.0 and 1.18
[ C ] 3.0 and 1.15
[ D ] 1.5 and 1.5
Answer : A
38 In Limit state method of design, the factor of safety for concrete and steel respectively are
[ A ] 3.00 and 1.80
[ B ] 1.50 and 1.18
[ C ] 1.50 and 1.15
[ D ] 1.50 and 1.50
Answer : C
39 Specific weight of Reinforced cement concrete is
[ A ] 24 N/m3
[ B ] 24 kN/m3
[ C ] 25 N/m3
[ D ] 25 kN/m3
Answer : D
40 The tensile strength of concrete is about ________ of its compressive strength
[ A ] 10% to 15%
[ B ] 30% to 40%
[ C ] 50%
[ D ] 60% to 75%
Answer : A
41 The shrinkage strain of concrete is generally taken as
[ A ] 0.3
[ B ] 0.03
[ C ] 0.003
[ D ] 0.0003
Answer : D
42 The tensile strength of concrete is given by
[ A ] 0.45 vfCK
[ B ] 0.60 vfCK
[ C ] 0.70 vfCK
[ D ] 0.90 vfCK
Answer : C
43 The ratio of bond stress for HYSD bars to that of plain bars
[ A ] 0.714
[ B ] 0.9
[ C ] 1.4
[ D ] 1.8
Answer : C
44 The proof stress in steel is the stress corresponding to the strain of
[ A ] 0.2
[ B ] 0.02
[ C ] 0.002
[ D ] 0.0002
Answer : C
45 In the mixer, the concrete should be mixed for at least
[ A ] 1 to 2 minutes
[ B ] 2 to 3 minutes
[ C ] 3 to 5 minutes
[ D ] 5 to 7 minutes
Answer : B
46 As per IS: 456-2000, the maximum size of aggregate is
[ A ] 1/4 of maximum thickness of member
[ B ] 1/4 of minimum thickness of member
[ C ] 1/5 of maximum thickness of member
[ D ] 1/5 of minimum thickness of member
Answer : B
47 Water used for mixing of concrete should be free from
(i)Oils
(ii)Salts
(iii)Acids
[ A ] i
[ B ] iii
[ C ] i and iii
[ D ] i, ii and iii
Answer : D
48 Modulus of elasticity of concrete is primarily influenced by
[ A ] Elastic properties of aggregate
[ B ] Curing of concrete
[ C ] Age of concrete
[ D ] Mix proportion and type of cement
Answer : A
49 As the workability increases compaction factor
[ A ] Decreases
[ B ] Increases
[ C ] Remains same
[ D ] None of the above
Answer : B
50 Shrinkage of concrete is mostly influenced by
[ A ] Environmental conditions
[ B ] Size of member
[ C ] Cement in concrete
[ D ] The total amount of water present in concrete
Answer : D
51 During the process of hardening of cement, _______ will takes place
[ A ] Bleeding
[ B ] Segregation
[ C ] Hydration
[ D ] All the above
Answer : C
52 Due to Bleeding action concrete becomes
[ A ] Weak
[ B ] Strong
[ C ] Hard
[ D ] Durable
Answer : A
53 About 70% to 80% of cement is contributed by
[ A ] Tricalcium silicate and Tricalcium aluminate
[ B ] Tricalcium silicate and Dicalcium silicate
[ C ] Tricalcium Aluminate and Dicalcium silicate
[ D ] Tricalcium Aluminate and Tetra calcium Aluminoferrite
Answer : B
54 When compared to ordinary Portland cement, Rapid hardening Portland cement contains
______________ amount of lime content
[ A ] Equal
[ B ] Greater
[ C ] Lesser
[ D ] Zero
Answer : B
55 The following compound has the property of early strength as well as ultimate strength
[ A ] C3S
[ B ] C2S
[ C ] C3A
[ D ] C4AF
Answer : A
56 Which of the following compounds is considered to be an undesirable compound for cement
[ A ] C3S
[ B ] C2S
[ C ] C3A
[ D ] C4AF
Answer : D
57 Which of the following compound is susceptible to be attached by alkalies and salts
[ A ] C3S
[ B ] C3S
[ C ] C3A
[ D ] C3AF
Answer : C
58 The heat generated in ordinary cement at the end of 3 days is about
[ A ] 60 cal/g
[ B ] 80 cal/g
[ C ] 100 cal/g
[ D ] 120 cal/g
Answer : B
59 Low heat cement contains more amount of __________ than that of ordinary Portland
cement
[ A ] C3S
[ B ] C2S
[ C ] C3A
[ D ] None of the above
Answer : B
60 In Portland Blast furnace slag cement, the blast furnace slag content shall not exceed
[ A ] 50%
[ B ] 65%
[ C ] 80%
[ D ] 90%
Answer : B
61 White cement contains less amount of ___________
[ A ] Lime
[ B ] Silica
[ C ] Alumina
[ D ] Iron oxide
Answer : D
62 In fineness test on cement, residue left on I.S. sieve no.9 shall not exceed __________ by
weight of the sample of cement
[ A ] 5%
[ B ] 10%
[ C ] 15%
[ D ] 20%
Answer : B
63 Ordinary Portland cement requires a specific surface of
[ A ] 1250 cm2/gm
[ B ] 2250 cm 2/gm
[ C ] 3250 cm 2/gm
[ D ] 3500 cm 2/gm
Answer : B
64 The maximum percentage of chemical ingredient of cement is
[ A ] Iron oxide
[ B ] Silica
[ C ] Lime
[ D ] Magnesium oxide
Answer : C
65 The minimum percentage of chemical ingredient of cement is
[ A ] Iron oxide
[ B ] Silica
[ C ] Lime
[ D ] Magnesium oxide
Answer : D
66 Efflorescence in cement is caused due to an excess of
[ A ] Alkalies
[ B ] Silica
[ C ] Iron oxide
[ D ] Alumina
Answer : A
67 Dicalcium silicate (C2S)
[ A ] rates rapidly
[ B ] Hardens rapidly
[ C ] Generates less heat of hydration
[ D ] Has less resistance to sulphate attack
Answer : C
68 Tricalcium aluminate (C3A)
[ A ] Hydrating less rapidly
[ B ] Is a redundant compound
[ C ] To be attacked by alkalies and salts
[ D ] None of these
Answer : C
69 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 : A
70 For mass concrete work, the type of cement preferable is
[ A ] Ordinary Portland cement
[ B ] Rapid hardening cement
[ C ] Low heat cement
[ D ] Blast furnace slag cement
Answer : C
71 Le-chatelier apparatus is used for
[ A ] Fineness test
[ B ] Consistency test
[ C ] Soundness test
[ D ] Compressive strength test
Answer : C
72 The diameter of the Vicat plunger is 10 mm and its length varies form
[ A ] 40 mm
[ B ] 50 mm
[ C ] 55 mm
[ D ] 60 mm
Answer : B
73 Inert material of a cement concrete mix, is
[ A ] Water
[ B ] Aggregate
[ C ] Cement
[ D ] None of these
Answer : B
74 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
75 Workability of concrete for a given water content is good, if the aggregates are
[ A ] Rounded
[ B ] Irregular
[ C ] Angular
[ D ] Flaky
Answer : A
76 Setting time of cement increases by adding
(i)gypsum
(ii)sodium oxide
(iii)calcium chloride
[ A ] i
[ B ] i and ii
[ C ] i and iii
[ D ] i, ii and iii
Answer : A
77 The cement becomes useless if its absorbed moisture content exceeds
[ A ] 1%
[ B ] 2%
[ C ] 3%
[ D ] 5%
Answer : D
78 The size of fine aggregates does not exceed
[ A ] 2.75 mm
[ B ] 3.75 mm
[ C ] 4.75 mm
[ D ] 5.75 mm
Answer : C
79 Water used for mixing concrete should be
[ A ] Slightly acidic
[ B ] Free from bacteria
[ C ] Distilled
[ D ] Potable
Answer : D
80 The workability of concrete is mostly influenced by its
[ A ] Water cement ratio
[ B ] Aggregate cement ratio
[ C ] Cement content
[ D ] Water content
Answer : A
81 Chief constituent of ordinary Portland cement is
[ A ] Lime
[ B ] Alumina
[ C ] Magnesia
[ D ] Iron oxide
Answer : A
82 The heat of hydration for low heat cement at the age of 7 days shall not exceed
[ A ] 80 cal / gm
[ B ] 75 cal / gm
[ C ] 70 cal / gm
[ D ] 65 cal / gm
Answer : D
83 Cement is obtained by burning a mixture of the following materials
[ A ] Siliceous materials
[ B ] Argillaceous materials
[ C ] Calcareous materials
[ D ] All the above
Answer : D
84 For determining the compressive strength test on cement is, the percentage amount of
water to be added as (Pa = Percentage of water for required consistency)
[ A ] 0.25 Pa + 2.5
[ B ] 0.25 Pa + 3.5
[ C ] 0.35 Pa + 2.5
[ D ] 0.35 Pa + 3.5
Answer : B
85 Minimum compressive strength of cement required at the age of 3 days for ordinary
Portland cement of grade 33 is
[ A ] 1.15 N/mm2
[ B ] 11.5 N/mm2
[ C ] 2.10 N/mm2
[ D ] 21 N/mm2
Answer : B
86 Bulking of sand takes place due to
[ A ] Surface tension
[ B ] Viscosity
[ C ] Capillarity
[ D ] None of the above
Answer : A
87 Creep coefficient is the ratio of
[ A ] Ultimate Creep strain to elastic strain
[ B ] Elastic strain to ultimate Creep strain
[ C ] Elastic strain to plastic strain
[ D ] Plastic strain to elastic strain
Answer : A
88 Generally the strength of concrete is represented by the crushing stress of concrete cube of
size
[ A ] 50 mm
[ B ] 100 mm
[ C ] 150 mm
[ D ] 250 mm
Answer : C
89 As per IS:1139, the characteristic yield strength for hot rolled High yield strength deformed
bars is
[ A ] 250 N/mm2
[ B ] 415 N/mm2
[ C ] 500 N/mm2
[ D ] 550 N/mm2
Answer : B
90 As per IS:1139, the characteristic yield strength for cold twisted deformed bars is
[ A ] 250 N/mm2
[ B ] 415 N/mm2
[ C ] 500 N/mm2
[ D ] 550 N/mm2
Answer : C
91 For reinforced concrete work, aggregates having a nominal size of ——– are generally used
[ A ] 20 mm
[ B ] 40 mm
[ C ] 50 mm
[ D ] 60 mm
Answer : A
92 The proportion of coarse aggregates to fire aggregates in structural concrete is usually
[ A ] 0.50 – 1.25
[ B ] 1.25 – 4.50
[ C ] 1.50 – 2.50
[ D ] 0.25 – 0.75
Answer : C
93 Fly ash when added to concrete
[ A ] Acts as aggregates
[ B ] Acts as pozzolona
[ C ] Improves appearance
[ D ] Reduces setting time
Answer : B
94 As per IS:456, the strength of concrete sample is less than
[ A ] The characteristic strength minus 1.35times the standard deviation
[ B ] 0.80 times the characteristic strength
[ C ] Greater of (a) and (b)
[ D ] None of the above
Answer : C
95 Characteristic strength of steel has been defined as
[ A ] 0.1 % proof stress
[ B ] 0.2 % proof stress
[ C ] 0.4 % proof stress
[ D ] Equal to proof stress
Answer : B
96 For Ordinary Portland cement concrete exposed to dry and hot weather conditions, good
moist curing period is
[ A ] 7 days
[ B ] 10 days
[ C ] 14 days
[ D ] None of the above
Answer : B
97 As per IS: 456-2000, recommended value for standard deviation for concrete mix from M30
to M50 is
[ A ] 1 N/mm2
[ B ] 2 N/mm2
[ C ] 4 N/mm2
[ D ] 5 N/mm2
Answer : D
98 As per 1S: 456-2000, minimum grade of concrete in seat water constructions is
[ A ] M20
[ B ] M25
[ C ] M30
[ D ] M50
Answer : C
99 The section of a reinforced beam where most distant concrete fiber in compression and
tension in steel attains permissible stresses simultaneously is called
(i)Balanced section
(ii)Economic section
(iii)Critical section
[ A ] i
[ B ] i and ii
[ C ] i and iii
[ D ] i, ii and iii
Answer : D
100 As the percentage of steel increases
[ A ] Depth of neutral axis decreases
[ B ] Depth of neutral axis increases
[ C ] Lever arm increases
[ D ] None of the above are correct
Answer : B
