Home Civil Engineering Concrete Technology Most Important MCQs Part: 1

Concrete Technology Most Important MCQs Part: 1

1 - The slurry, in its movement down the kiln, encounters a progressively higher temperature. At first, the water is driven off and ___ is liberated.

CO2

2 - ____ cement is used for formwork that can be removed earlier and reused in other areas which save the cost of formwork.

Rapid Hardening Cement

3 - ____ cement is used for formwork that can be removed earlier and reused in other areas which save the cost of formwork.

Rapid Hardening Cement

4 - ____ cement is used for formwork that can be removed earlier and reused in other areas which save the cost of formwork.

Rapid Hardening Cement

5 - _______ % is the range for absorptivity of this concrete.

0-1

6 - _______ % is the range for porosity of this concrete.

44930

7 - _______ cement content to avoid shrinkage cracking due to temperature cycle in mass concrete.

Maximum

8 - ________ has designated the concrete mixes into a number of grades as M10, M15.

IS 456-2000

9 - ________ is also something used as the aggregate component of lightweight concretes.

Diatomite

10 - ________ is not use to make Portland Cement (PC)?

Sand

11 - ________ is the most commonly used.

Pumice

12 - ________ viscosity liquid monomers are impregnated with the hardened cement composite structure.

Low

13 - _________ cement content to avoid shrinkage cracking due to temperature cycle in mass concrete.

Maximum

14 - __________ has designated the concrete mixes into a number of grades as M10, M15.

IS 456-2000

15 - __________ water-cement ratio content to give adequate durability for the particular site conditions.

Maximum

16 - ___________ cost of maintenance of the structure __________ construction due to quality works.

Minimize, after

17 - ___________ is practical in field test.

Kelly Ball Test

18 - ___________ mm thickness is not available in concrete cloth.

18

19 - ___________ quality construction ___________ the wastage of materials.

Good, reduce

20 - ___________ water-cement ratio content to give adequate durability for the particular site conditions.

Maximum

21 - ____________ mm nominal maximum size aggregates gives optimum strength.

9.5 and 12.5

22 - “C4AF is not a true compound.” Is this statement true or false?

TRUE

23 - “C4AF is not a true compound.” Is this statement true or false?

TRUE

24 - “Damp proofing cracks along with the foundation”. Is it true or false?

TRUE

25 - “Damp proofing is cheaper in the beginning, but leads to more expensive problems later on”. Is it true or false?

TRUE

26 - “Fine aggregate do not show any bulking when it is absolutely dry”. Is this statement true or false?

TRUE

27 - “High Performance concrete works out to be economical”. Is it true or false?

TRUE

28 - “However, fall of temperature and carbonation may also cause the shrinkage”. Is this statement true or false?

TRUE

29 - “HPC is not used in high span bridges”. Is it true or false?

FALSE

30 - “If the concrete is placed in 100% relative humidity for a length of time then there WON’T be any shrinkage”. Is it true or false?

TRUE

31 - “In bridges, HDC is used”. Is it true or false?

TRUE

32 - “In bridges, HSC is used”. Is it true or false?

TRUE

33 - “NaOH is the example of retenders”. Is it true or false?

FALSE

34 - “Shrinkage in concrete is caused mainly by loss of water by evaporation or by hydration of cement”. Is this statement true or false?

TRUE

35 - “Shrinkage in concrete is caused mainly by loss of water by evaporation or by hydration of cement”. Is this statement true or false?

TRUE

36 - “Size of the kiln needed to manufacture the cement is bigger for wet process”. Is the statement true or false?

TRUE

37 - “The machinery and equipments do not need much maintenance”. Is the statement true or false?

TRUE

38 - “The machinery and equipments do not need much maintenance”. Is the statement true or false?

FALSE

39 - “The shape of specimen used in compression test is Cube and cylinder”.

TRUE

40 - “There is necessary to minimize the use of salt water in RCC”. Is this statement true or false?

TRUE

41 - “Water proofing admixtures are available in powder, paste or liquid and gaesous form”. Is this statement true or false?

FALSE

42 - “Water repelling materials like soda, potash soaps, etc make the concrete pervious”. Is this statement true or false?

FALSE

43 - “When chalk is used, _______” Choose the most suitable option.

It is finely broken up and dispersed in water in a wash mill

44 - “Where the matrix is extremely dense, a weak aggregate may become the weak”. Is this statement true or false?

TRUE

45 - “Where the matrix is extremely dense, a weak aggregate may become the weak”. Is this statement true or false?

TRUE

46 - “Zinc is the example of retenders”. Is it true or false?

TRUE

47 - ”Prepared raw mix is fed into the rotary kiln”. Is the statement true or false?

TRUE

48 - 1% of voids in a concrete mix would reduce its strength by about______________?

0.05

49 - A ________ paste structure undergoes ________ creep.

Poor, high

50 - A _________ paste structure undergoes _________ creep.

Poor, high

51 - A ___________ paste structure undergoes ___________ creep.

Poor, high

52 - A beam curved in plan is designed for_______________?

bending moment, shear and torsion

53 - A compaction factor of .85 for a cement concrete sample indicates ___________

Low workability

54 - A concrete having a slump of 6.5 cm, is said to be

plastic

55 - A concrete using an air entrained cement

is more plastic and workable

56 - A construction joint is provided where

all the above.

57 - A data acquisition system capable of digitally recording and storing load and deflection data at least ___________

10 times per sec

58 - A discontinuity that occurs during the casting of molten metal which may be caused by the splashing, surging, interrupted pouring is___________

Cold shut

59 - A flaky aggregate is said to be elongated if its length is

twice the mean size

60 - A fully saturated soil is said to be________________?

two phase system with soil and water

61 - A higher modular ratio shows____________?

lower compressive strength of concrete

62 - A higher temperature of fresh concrete results in a __________ hydration of cement.

More rapid

63 - A lower ratio leads to

High strength

64 - A lower ratio leads to ___

Higher strength and durability

65 - A lower ratio leads to ___

Higher strength and durability

66 - A lower ratio leads to _____

High strength

67 - A maximum value of ___ percent is allowed for WBM base course in Indian conditions.

40

68 - A maximum value of ___ percent is allowed for WBM base course in Indian conditions.

40

69 - A maximum value of ___ percent is allowed for WBM base course in Indian conditions.

40

70 - A maximum value of _________ percent is allowed for WBM base course in Indian conditions.

40

71 - A maximum value of 40%age is allowed for WBM base course in Indian conditions.

Aggregates to be used for wearing course, the impact value shouldn’t exceed __ percent.

72 - A maximum value of 40%age is allowed for WBM base course in Indian conditions.

Aggregates to be used for wearing course, the impact value shouldn’t exceed __ percent.

73 - A ratio of core height-to-diameter of ___ gives a standard cylinder test.

2

74 - A second name for compression wave is __________

Lamb wave

75 - A T-shaped retaining wall mainly conssits of_________________?

three cantilevers

76 - A value less than 10 signifies an exceptionally _________ while above 35 would normally be regarded as _________

Strong aggregates, weak aggregates

77 - According to fig. what is the approx. value of strength of 50mm cube in MPa for gel-space ratio .6?

40

78 - According to geological origin, aggregates is/are classified into __________ types.

2

79 - According to I.S. : 456, the number of grades of concrete mixes, is

7

80 - According to IRC:15-2002, _______% Fly ash is required to be replaced with the total cementitious materials.

25

81 - According to IRC:15-2002, Maximum nominal size of aggregates is ________

20 mm crushed aggregates

82 - According to IRC:15-2011, _______% Fly ash is required to be replaced with the total cementitious materials.

20

83 - According to IRC:15-2011, Characteristic Flexural Strength at 28 days

4.5 N/mm2

84 - According to IRC:15-2011, maximum free W/C ratio for OPC is ________________

0.45

85 - According to IRC:15-2011, maximum free W/C ratio for PPC is _________

0.5

86 - According to IRC:15-2011, Maximum nominal size of aggregates

31.5 mm crushed aggregates

87 - According to IRC:15-2011, Minimum cement content for 4.5 N/mm2 characteristic flexural strength for OPC + fly ash mix OPC shall ____________

Shall not be less than 340 kg/ m3

88 - According to IRC:15-2011, Minimum cement content for 4.5 N/mm2 characteristic flexural strength for OPC shall _____________

Shall not be less than 360 kg/ m3

89 - According to IRC:15-2011, Minimum cement content for 4.5 N/mm2 characteristic flexural strength for PPC shall _________

Shall not be less than 425 kg/ m3

90 - According to IS : 382-1963, a good aggregate should be

all the above.

91 - According to IS : 456-1978, the fiexural strength of concrete is________________?

directly proportional to square root of compressive strength

92 - According to IS: 2386 part-IV, each layer is tamped ________ times in crushing test.

25

93 - According to IS: 456-1978, the maximum reinforcement in a column is_____________?

0.06

94 - According to Lamond and Pielert, it’s the ____ that exhibits creep upon application of load on a concrete specimen.

Cement paste

95 - According to size, aggregates is/are classified into __________ types.

4

96 - According to the recommendations of IS : 456-1978, the expansion joints

all the above.

97 - According to Water-Cement Ratio Law, the strength of workable plastic concrete

all the above.

98 - According to Whitney's theory, depth of stress block for a balanced section of a concrete beam is limited to_______________?

0.537 d

99 - ACI 305.R.91 specifies Evaporation rate __ kg/hr/m2 should be avoided to prevent plastic cracking.

>.5

100 - Adding water increases __________

Workability

101 - Addition of pozzolana to cement

none of these.

102 - Addition of pozzolana to cement causes

all the above.

103 - Addition of pozzolana to ordinary port land cement, causes

all the above.

104 - Admixtures which cause early setting, and hardening of concrete are called __________

Accelerators

105 - Aerated Concrete is _________

Light weight

106 - Aerated Concrete is ______________

Light weight

107 - Aerated concrete is made in the density of approx. _________ kg/m3.

350

108 - After casting, an ordinary cement concrete on drying

shrinks

109 - After finishing concrete surface must be kept ________

Wet

110 - After finishing concrete surface must be kept _________

Wet

111 - After finishing concrete surface must be kept __________

Wet

112 - After finishing concrete surface must be kept ___________

Wet

113 - After placing each layer in a slump cone, the concrete in the cone is tapped to remove remaining voids.

TRUE

114 - After the curing of 28 days, the concrete gains strength upto _____________

1

115 - After vacuum mixing, the volumetric shrinkage can be raised from 3–5% to __________ % in different cements.

45053

116 - Aggregate abrasion value is determined by__________

Los Angeles abrasion test

117 - Aggregate crushed before the application of full load of ___________

40ton

118 - Aggregate has therefore a direct effect on the long-term deformations of concrete because __________

High elastic modulus aggregate will produce a stiffer concrete that will have relatively higher resistance to deformation

119 - Aggregates to be used for wearing course, the impact value shouldn’t exceed __ percent.

30

120 - Aggregates with a specific gravity of _________ are called lightweight aggregates.

<2.4

121 - Aggregates with moisture movement and _________ elastic modulus cause a _________ amount of creep.

Low, higher

122 - Air contents should be _________ % by volume.

44989

123 - Air entrainment in concrete increases ___________

Workability

124 - Air entrainment in concrete increases ____________

Workability

125 - Allowable shear strength of concrete, depends upon

shear strength

126 - Alumina in excess causes ____

Reduces the strength of the cement

127 - Alumina in excess causes ____

Reduces the strength of the cement

128 - Among the below statement, which one is correct for dry process?

The amount of heat required is less, so the required fuel amount is less

129 - Among the below statement, which one is correct for wet process?

The amount of heat required is high, so the required fuel amount is high

130 - An aggregate is known as cyclopean aggregate if its size is more than

75 mm

131 - An aggregate is said to be flaky if its least dimension is less than

3/5th of mean dimension

132 - An aggregate is said to be flaky if its least dimension is less than ___________

3/5th of mean dimension

133 - An aggregate is said to be flaky, if its least dimension is less than

3/5 mean dimension

134 - 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

13.5 mm.

135 - An excess of flaky particles in concrete aggregates

all the above.

136 - An ideal ware house, is provided

all the above.

137 - An ordinary Portland cement when tested for its fineness, should not leave any residue on I.S. seive No. 9, more than

0.1

138 - An ultrasonic pulse velocity test is an _____________

In-situ, nondestructive test

139 - Approximate percentage range of A2O3 in OPC is ___

44995

140 - Approximate ratio of direct tensile strength to flexural strength is ____________

0.5

141 - Approximate ratio of strength of the 30 cm cube to that of 15 cm cube is _____________

0.9

142 - Approximate ratio of the strength of the cement conc of 7 days to that of 28 days (2/3)

0.75

143 - As compared to ordinary portland cement, high alumina cement has______________?

higher initial setting time but lower final setting time

144 - As per Whitney's theory, the maximum moment of resistance of the balanced section of a beam of width b and effective depth d is given by_______________?

^acybd2

145 - As the hydration proceeds the deposits of hydrated products on the original cement grains makes the diffusion of water to unhydrated nucleus ____

Very difficult

146 - As the materials pass through the kiln their temperature is rised upto ____

1300-1600 °C

147 - ASTM D1414 (D 1414) covers multiple properties of _____________

O ring

148 - At constant workability, what is the reduction in mixing water?

5-15%

149 - At constant workability, what is the reduction in mixing water?

5-15%

150 - At least 30 __ of crosshead travel or more for high elongation materials.

inches

151 - At normal temperatures addition of sugar _____________ per cent have little effect on the rate of hydration

.05-1

152 - At the construction stage, binding wires ____________

Should not touch the formwork

153 - At what temperature the heat is supplied to concrete to remove moisture in oC?

120-150

154 - Batching error means inaccuracy in the quantity of

all the above.

155 - Begin the test by separating the grips at a speed of _______________

20 inches per minute

156 - Bulk density of the silica fume varies from

130-600 kg/m3

157 - Bulking ___________ with increase in moisture.

First increase then decrease

158 - Bulking of sand is

swelling of sand when wetted.

159 - Bulking of sand is maximum if moisture content is about____________?

0.04

160 - C3 S and C2S require approximately the _____________ amount of water for hydration.

Same

161 - Calculate standard consistency(%) when 100 ml of water is added in 1000 g of cement.

10

162 - Calipers, capable of reading the dimensions of test specimens to an accuracy of ____________

.1mm

163 - Carbonic Acid + Ca(OH)2 ⇨ X. What is the main compound in X?

CaCO3

164 - Cement has ________ % volumetric shrinkage after curing.

5

165 - Cement not more than ________ months old should be used.

3

166 - Cement used for normal concrete construction, is obtained by burning a mixture of

silicious, argillaceous and calcareous materials

167 - Chemically active pore fillers __________ the setting of concrete.

Accelerates

168 - Chemically active pore fillers ____________ the setting of concrete.

Accelerates

169 - Chemically inactive pore fillers __________ the workability.

Improve

170 - Chemically inactive pore fillers ____________ the workability.

Improve

171 - Classification of admixtures are classified into ________ types.

2

172 - Clay minerals are found in most _________

Sedimentary environment

173 - Coarse aggregates which has been used in this is of __________

10 mm

174 - Coefficient of thermal expansion of concrete is ___ coefficient of thermal expansion in aggregates.

Directly proportional

175 - Coefficient of thermal expansion of concrete is ________ coefficient of thermal expansion in aggregates.

Directly proportional

176 - Compressive strength of hardened concrete is done by _______

Cube test

177 - Compressive strength of hardened concrete is done by _________

Cube test

178 - Concentration of water-soluble sulphates in water ___________ ppm for mild exposure.

<150

179 - Concentration of water-soluble sulphates in water ___________ ppm for mild exposure.

<150

180 - Concentration of water-soluble sulphates in water ___________ ppm for severe exposure.

150-10000

181 - Concentration of water-soluble sulphates in water ___________ ppm for severe exposure.

150-10000

182 - Concrete containing

All the above.

183 - Concrete containing silica fume can have very __________ strength and can be very __________

High, Durable

184 - Concrete exhibits initial elastic strain which depends on __________

Magnitude and rate of applied stress

185 - Concrete gains strength due to

hydration of cement

186 - Concrete having 28- days’ compressive strength in the range of 60 to 100 MPa.

HPC

187 - Concrete having 28-days compressive strength in the range of 100 to 150 MPa.

VHPC

188 - Concrete is not recommended to be placed at a temperature above _________oC.

40

189 - Concrete is not recommended to be placed at a temperature below __________oC.

5

190 - Concrete is unsuitable for compaction by a vibrator if it is

plastic

191 - Concrete mainly consists of

all the above.

192 - Concrete placed in cold weather will take __________ time to gain strength.

More

193 - Concrete placed in cold weather will take ____________ time to gain strength.

More

194 - Constant head permeameter is used to test permeability of_______________?

coarse sand

195 - Construction joints are generally provided in concrete

all the above.

196 - Construction joints are provided

all the above.

197 - Content of CaO in silica fume?

<1

198 - Content of SiO2 in silica fume is ___________

85-97%

199 - Content of SiO2 in silica fume?

85-97%

200 - Contractors place blankets over the concrete to ____________

Slow the rate of evaporation

201 - Creep ___ as the age of application of load _____

Decrease, increase

202 - Creep is ____ to the strength of concrete.

Inversely proportional

203 - Creep is _________ to the strength of concrete.

Inversely proportional

204 - Creep is ____________

Time dependent

205 - Critical section for shear in case of flat slabs is at a distance of_______________?

d/2 from periphery of column/capital/ drop panel

206 - Crushed stone, gravel and ordinary sand are examples of ___________

Normal-weight aggregate

207 - Cube strength of controlled concrete to be used for pretensioned and post-tensioned work respectively should not be less than__________________?

42 MPa and 35 MPa

208 - Curing

all of the above.

209 - Curing a concrete for long period ensures better

all the above.

210 - Curing of pavements, floors, roofs and slabs, is done by

ponding method

211 - Damp proofing __________ resist water well enough.

Does not

212 - Damp proofing __________ the process of water absorption.

Slows

213 - Damp proofing ____________ resist water well enough.

Does not

214 - Damp proofing is done with a __________ based mixture.

Tar

215 - Density of no fines concrete with light weight aggregate vary from __ kg/m3.

<300

216 - Density of no fines concrete with light weight aggregate vary from ________ kg/m3.

<300

217 - Density of no fines concrete with normal aggregate vary from __ kg/m3.

1600-1900

218 - Depending on the degree of workability and placing condition determine the ___________

Slump value

219 - Depending on the economical availability and dimensions of the structure determine the _____________

The maximum size of aggregate

220 - Determine the _______ either from strength considerations or from durability considerations.

The minimum water-cement ratio

221 - Determine the amount of cement per unit volume of concrete from ______________

The maximum size of aggregate and the amount of mixing water

222 - Diameter of Round Steel Fiber lies in the range of _______ mm.

.25-.75

223 - Diameter of Round Steel Fiber lies in the range of ________ mm.

.25-.75

224 - Di-calcium silicate (C2S)

generates less heat of hydration

225 - Does this reduce handling time?

TRUE

226 - DPC _________ effective used in concretes that are in contact with water under pressure?

Doesn’t

227 - Dry intervals in surface wetting leads to __________

Cracking

228 - Dry intervals in surface wetting leads to __________

Cracking

229 - Dry intervals in surface wetting leads to ___________

Cracking

230 - Dry intervals in surface wetting leads to ____________

Cracking

231 - Due to circumferential action of the spiral in a spirally reinforced column________________?

both the capacity of column and ductility of column increase

232 - Due to low w/c ratio

It causes problems

233 - Due to low w/c ratio ___________

It causes problems

234 - Due to low w/c ratio _____________

It causes problems

235 - Due to shrinkage stresses, a simply supported beam having reinforcement only at bottom tends to_____________?

deflect downward

236 - Durability of concrete is proportional to _________

Cement aggregate ratio

237 - During compression test of cast iron, the failure occurs i.e. the crack appears along the _________

Diagonal

238 - During compression test of cast iron, the failure occurs i.e. the crack appears along the __________

Diagonal

239 - During compression test of cast iron, the failure occurs i.e. the crack appears along the _____________

Diagonal

240 - During radiography test, which region absorbs less radiation and transmits more?

Low density region

241 - During radiography test, which region absorbs less radiation and transmits more?

Low density region

242 - During radiography test, which region absorbs less radiation and transmits more?

Low density region

243 - During radiography test, which region absorbs less radiation and transmits more?

Low density region

244 - Efflorescence in cement is caused due to an excess of

alkalis

245 - Entrainment of air also improves workability and durability.

TRUE

246 - Entrainment of air also improves workability and durability.

TRUE

247 - Entrainment of air while applying cement, increases resistance to frost action.

TRUE

248 - Entrapped air normally exists in the form of relatively _________ air voids.

Large

249 - Entrapped air normally exists in the form of relatively __________ air voids.

Large

250 - Evaluation of cracks ________ be determined before cracking.

Can

251 - Evaluation of cracks _________ be determined after cracking.

Can

252 - Excess in lime causes ___

The cement to expand and disintegrate

253 - Excess in lime causes ___

The cement to expand and disintegrate

254 - Expansion joints are provided if the length of concrete structures exceeds

45 m

255 - Expansion should not be more than _____________

10mm

256 - Final setting time of cement should not be more than

10 hours

257 - Find the odd one out.

Surkhi

258 - Find the odd one out.

Volcanic tuffs

259 - Find the odd one out.

Natural derivatives

260 - Find the odd one out.

Super plasticizers

261 - Find the odd one out.

Super plasticizers

262 - Fine sand bulks __________ than coarse sand.

More

263 - For a concrete mix 1:3:6 and water cement ratio 0.6 both by weight, the quantity of water required per bag, is

14 kg

264 - For a continuous slab of 3 m x 3.5 m size, the minimum overall depth of slab to satisfy vertical deflection limits is__________________?

75 mm

265 - For a good concrete

All the above.

266 - For a reinforced concrete section, the shape of shear stress diagram is_______________?

parabolic above neutral axis and rectangular below neutral axis

267 - 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_______________?

is always less than 1

268 - For an ordinary Portland cement

initial setting time is not less than 30 minutes

269 - For batching 1:3:6 concrete mix by volume, the ingredients required per bag of 50 kg cement, are:

105 litres of sand and 210 litres of aggregates

270 - For compacting large sections of mass concrete in structures, the type of vibrator used is ________________

Internal vibrator

271 - For compacting plain concrete road surface of thickness less than 20 cm, we use

screed vibrator

272 - For complete hydration of cement the w/c ratio needed is ____

More than 0.35 but less than 0.60

273 - For concrete exposed to a very aggressive environment the w/c should be lower than

0.4

274 - For concrete exposed to a very aggressive environment the w/c should be lower than

0.4

275 - For concrete exposed to a very aggressive environment the w/c should be lower than _________

0.4

276 - For concreting of heavily reinforced sections without vibration, the workability of concrete expressed as compacting factor should be________________?

above 0.92

277 - For concreting tunnel linings, tran-portation of concrete is done by

pumps

278 - For construction of structures in sea water, the cement generally preferred to, is

Portland-pozzolana cement

279 - For ensuring quality of concrete, use

graded aggregates

280 - For given water content, workability decreases if the concrete aggregates contain an excess of

all the above.

281 - For given workability the grading requiring the least amount of water is one that gives

greatest surface area for the given cement and aggregates

282 - For hardness test of copper in Brinell hardness tester, the diameter of ball is ___________

5mm

283 - For high-strength concrete, a cement should produce a minimum 7-days mortar-cube strength of approximately ___ MPa.

30

284 - For making cement paste, what is the amount of water we need?

25% water by weight of dry cement

285 - For preparing a test-specimen, it is necessary

all the above.

286 - For preparing ordinary concrete, the quantity of water used, is

5% by weight of aggregates plus 30% of weight of cement

287 - For quality control of Portland cement, the test essentially done is

all the above.

288 - For road pavements, the cement generally used, is

rapid hardening cement

289 - For the construction of cement con-certe dams, the maximum permissible size of the aggregates, is

40 mm

290 - For the construction of cement concrete floor, the maximum permissible size of aggregate, is

10mm

291 - For the construction of cement concrete floor, the maximum permissible size of aggregate, is

10 mm

292 - For the construction of thin R.C.C. structures, the type of cement to be avoided, is

blast furnace slag cement

293 - For the design of retaining walls, the minimum factor of safety against overturning is taken as_____________?

2

294 - For the given slump and maximum size of coarse aggregate determine the ______________

The amount of mixing water

295 - For walls, columns and vertical faces of all structural members, the form work is generally removed after

24 to 48 hours

296 - For walls, columns and vertical faces of all structural members, the form work is generally removed after______________?

24 to 48 hours

297 - For walls, columns and vertical faces of all structural members, the form work is generally removed after_______________?

24 to 48 hours

298 - Gel/Space ratio = x = Volume of gel / Space available = 0.657 C / 0.319 C+ Wo. Here C stands for?

Weight of cement in g

299 - Gel/Space ratio = x = Volume of gel / Space available = 0.657 C / 0.319 C+ Wo. Here Wo stands for?

Volume of mixing water in ml

300 - Generally angular aggregates are the example of natural aggregates. Is this statement true or false?

TRUE

301 - Generally heavy weight aggregate obtained from ______________

Minerals ores

302 - Generally rounded aggregates are the example of natural aggregates. Is this statement true or false?

TRUE

303 - Generally what is the w/c ratio?

0.5

304 - Glass fiber is made up from _______ individual filaments.

200-400

305 - Good quality construction _________ the wastage of materials, smooth function of the team.

Decreases

306 - Grading of sand causes great variation in

all the above.

307 - Gypsum is added for

controlling setting time

308 - Gypsum reacts with ____________ to form calcium sulfo aluminates and calcium sulfo ferrite.

C4AF

309 - Half of the main steel in a simply supported slab is bent up near the support at a distance of x from the center of slab bearing where x is equal to________________?

44933

310 - Hardening of cement occurs at

none of these.

311 - Harshness in concrete is due to the excess of _____________

Middle sized particle

312 - High carbon content in the steel causes_______________?

increase in tensile strength but decrease in ductility

313 - High strength concrete is defined purely on the basis __________

Compressive strength

314 - High temperature

decreases the strength of concrete

315 - Higher resin dosage is recommended when using ________

Fine aggregates

316 - Higher velocities indicate __________

Good quality and continuity of the material

317 - Higher workability of concrete is required if the structure is

thick and heavily reinfored.

318 - High-Performance Concrete is ____________ as compared to Normal Strength Concrete.

More brittle

319 - Horizontal construction joints in concrete walls are generally provided at

all the above.

320 - How can we prevent cracks in concrete structures?

Low w/c ratio

321 - How many layers of concrete are placed to fill a slump cone?

3 equal layers by volume

322 - How many moulds required for compression strength test of cement?

3

323 - How many principal thermal properties are there for aggregates?

3

324 - How many times in each layer of concrete rodded in a slump cone?

25

325 - How many types of shrinkages, caused due to cooling and carbonation?

2

326 - How many types of shrinkages, caused due to cooling and carbonation?

2

327 - How many types of shrinkages, caused due to loss of water?

3

328 - How many types of shrinkages, caused due to loss of water?

3

329 - How many types of sulphates attack occur in concrete?

2

330 - How to improve the workability of concrete.

Increase the w/c ratio

331 - Hydration of cement is due to chemical action of water with

All the above.

332 - Identify the type of destructive testing ______________

Creep test

333 - Identify the type of destructive testing.

Creep test

334 - Identify the type of destructive testing.

Creep test

335 - If 1500 g of water is required to have a cement paste 1875 g of normal consistency, the percentage of water is,

0.25

336 - If 20 kg of coarse aggregate is sieved through 80 mm, 40 mm, 20 mm, 10 mm, 4.75 mm, 2.36 mm, 1.18 mm, 600 micron, 300 micron and 150 micron standard sieves and the weights retained are 0 kg, 2 kg, 8 kg, 6 kg, 4 kg respectively, the fineness modulus of the

7.4

337 - If 50 kg of fine aggregates and 100 kg of coarse agregates are mixed in a concrete whose water cement ratio is 0.6, the weight of water required for harsh mix, is

12 kg

338 - If 60% aggregates doesn’t pass through the 2.36mm sieve, then what would be the value of Aggregate impact value?

0.4

339 - If 60% aggregates doesn’t pass through the 2.36mm sieve, then what would be the value of Aggregate impact value?

0.4

340 - If 60% aggregates doesn’t pass through the 2.36mm sieve, then what would be the value of Aggregate impact value?

0.4

341 - If 60% aggregates doesn’t pass through the 2.36mm sieve, then what would be the value of Aggregate impact value?

0.4

342 - If 60% aggregates doesn’t pass through the 2.36mm sieve, then what would be the value of Aggregate impact value?

0.4

343 - If a beam fails in bond, then its bond strength can be increased most economi-cally by___________?

using thinner bars but more in number

344 - If a grading curve is horizontal bet-wen the portions of 20 mm I.S. Sieve and 4.75 mm I.S. Sieve, the graded aggregates do not contain

all the above.

345 - 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

40.5 mm

346 - If compaction factor of concrete is .90, then workability is ____________

Medium

347 - If concrete is exposed to repeated freezing and -thawing after final set, the final qualities of the concrete may also be

Impair

348 - If creep effect is considered at a given load, the modulus determined is referred to as ______

Long term modulus of elasticity

349 - If fineness modulus of sand is 2.5, it is graded as

fine sand

350 - If h= height of sand when moist and h1 is the height when saturated then what is the percentage of bulking?

{(h-h1)/h1}*100

351 - If L1=Measurement taken after 24 hours of immersion in water at a temp. of 27 ± 20oC and L2=Measurement taken after 3 hours of immersion in water at boiling temperature. Then what is soundness of cement?

L1-L2

352 - If nominal shear stress tv exceeds the design shear strength of concrete xc, the nominal shear reinforcement as per IS : 456-1978 shall be provided for carrying a shear stress equal to__________________?

xv – TC

353 - If P, Y and Z are the weights of cement, fine aggregates and coarse aggregates respetively and W/C is the water cement ratio, the minimum quantity of water to be added to first batch, is obtained by the equation

0.3P + 0.1Y + 0.01Z = W/C x P

354 - If t1=Time at which water is first added to cement,t2=Time when needle fails to penetrate 5 mm to 7 mm from bottom of the mould,t3=Time when the needle makes an impression but the attachment fails to do so, then what is initial setting time?

t2-t1

355 - If t1=Time at which water is first added to cement,t2=Time when needle fails to penetrate 5 mm to 7 mm from bottom of the mould,t3=Time when the needle makes an impression but the attachment fails to do so,then what is final setting time?

t3-t1

356 - If the average compressive strength is 4000 kg/cm2 and standard deviation is 500, the co-efficient of variation is

0.125

357 - If the coefficient of the two materials differ by more than 5.4 * 10-6 per oC, then

Durability of concrete subjected to freezing

358 - If the coefficient of thermal expansion of coarse aggregates and cement paste differs too much, then what happen?

A large change in temperature may introduce

359 - If the depth of actual neutral axis in a beam is more than the depth of critical neutral axis, then the beam is called________________?

over-reinforced beam

360 - 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

25%.

361 - If the depth of neutral axis for a singly reinforced rectangular section is represented by kd in working stress design, then the value of k for balanced section_______________?

depends on as, only

362 - 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

2700 bags

363 - 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

18, 900 litres

364 - If the engineer-in-charge approves, the 10 cm cubes may be used for the work test of concrete provided maximum nominal size of aggregate, does not exceed

20 cm

365 - If the moisture content of 5 to 10% by weight, then the bulking of sand is increased by __

50

366 - If the moisture content of 5 to 10% by weight, then the bulking of sand is increased by __________

50

367 - 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___________________?

0.40 d

368 - If the size of panel in a flat slab is 6m x 6m, then as per Indian Standard Code, the widths of column strip and middle strip are__________________?

3.0 m and 3.0 m

369 - If the slump of a concrete mix is 60 mm, its workability is

medium

370 - If the storey height is equal to length of RCC wall, the percentage increase in strength is_____________?

10

371 - If the stress is removed, the specimen shows an instantaneous recovery strain ___ the elastic strain on loading.

Lower than

372 - If the value of fck is 100 then what will be the modulus of elasticity?

50000

373 - If the various concrete ingredients i.e. cement, sand and aggregates are in the ratio of 1:3:6, the grade of concrete, is

M 100

374 - If the voids of a soil mass are full of air only, the soil is termed as_______________?

dry soil

375 - If the volume of voids is equal to the volume of solids in a soil mass, then the values of porosity and voids ratio respectively are________________?

0.5 and 1.0

376 - If the Y is the reading of sand surface (ml) then what is the percentage of bulking?

% of bulking {(200/Y)-1} x100

377 - If there is continuous supply of H2O to the concrete during hydration, concrete expands due to absorption of water by the cement gel. Is it true or false?

TRUE

378 - If θ is creep coefficient then what is Elong?

Eshort /(1+θ)

379 - In a counterfort retaining wall, the main reinforcement in the stem at mid span is provided on_______________?

front face only

380 - In a dry environment, concrete strength will be loosed as much as ________ % in moist environment.

50

381 - In a dry environment, concrete strength will be loosed as much as _________ % in moist environment.

50

382 - In a dry environment, concrete strength will be loosed as much as __________ % in moist environment.

50

383 - In a dry environment, concrete strength will be loosed as much as ___________ % in moist environment.

50

384 - In a spherical dome subjected to concentrated load at crown or uniformly distributed load, the meridional force is always________________?

compressive

385 - In a spherical dome the hoop stress due to a concentrated load at crown is_______________?

tensile everywhere

386 - In case of hand mixing of concrete, the extra cement to be added is__________________?

0.1

387 - In cement hardening process, ___________ instants are very important.

2

388 - In charpy test specimen, the angle of v-notch section is ___________

45 degrees

389 - In charpy test specimen, the angle of v-notch section is ____________

45 degrees

390 - In Concrete core test the strength is __ at the top and ___ at the bottom.

Lowest, highest

391 - In counterfort retaining walls, the main reinforcement in the stem at support is_______________?

provided only on inner face

392 - In crushing test, dry aggregates passing through ________ mm sieve and retained ________ mm in a cylinder.

12.5, 10

393 - In making precast structural units for partition and wall lining purposes, the concrete should be __________

LWC

394 - In order to avoid segregation, the concrete should not be thrown from a height.

TRUE

395 - In order to obtain the best workability of concrete, the preferred shape of aggregate is_______________?

rounded

396 - In order to prevent this rapid reaction ___ is added to the clinker.

Gypsum

397 - In practice, shrinkage is measured simply as a:

Linear strain

398 - In prestressed concrete______________?

forces of tension and compressions remain unchanged but lever arm changes with the moment

399 - In reinforced concrete footing on soil, the minimum thickness at edge should not be less than______________?

150 mm

400 - In slump test, each layer of concrete is compacted by a steel rod 60 cm long and of 16 mm diameter for

25 times

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