This document contains 44 multiple choice questions about concrete technology. It tests knowledge on topics like the purpose of adding gypsum to cement, the function of aggregates in concrete, the properties imparted by different components of cement, types of vibrators used to compact concrete, factors that influence the strength and properties of concrete over time, and definitions of terms like water-cement ratio, consistency, workability, and gel space ratio. The answers to each question are provided at the end.
1. All type and none type question answer
Concrete technology 12%
From RKS
1. The gypsum is added to the cement for :
a) Providing high strength to the cement
b) Controlling the initial setting time of cement
c) Lowering the initial setting time of cement
d) All of the above
2. The function of aggregates in concrete is to serve as :
a) Binding material
b) Filler
c) Catalyst
d) All of these
3. The presence of tricalcium silicate in cement :
a) Hydrates the cement rapidly
b) Generates less heat of hydration
c) Offers high resistance of sulphate attack
d) All of these
4. The aggregate which pass through 4.75mm is sieve and entrirdyretain an 75 micron is
sieve is called :
a) Cyclopean aggregates
b) Coarse aggregate
c) Fine aggregate
d) All –in – aggregate
5. The slump test of concrete is used to measure is:
a) Consistency
b) Mobility
c) Homogenous
d) All the these
6. For compacting large sections of mass concrete in structures, the types of vibrator used is:
a) Internal vibrator
b) Screed vibrator
c) From vibrator
d) All the these
7. For compacting plain concrete or one way reinforced concrete floor the vibrator used is:
a) Internal vibrator
b) Screed vibrator
c) From vibrator
d) All of above
8. Concrete gains strength due to :
a) Chemical reaction of cement with sand and course aggregates
b) Evaporation of water from of concrete
c) Hydration of cement
d) All of the above
ER. SUNIL KUMAR YADAV 1
2. 9. Increase in fineness modulus of aggregate indicates :
a) Finer grading
b) Courses grading
c) Gap grading
d) All the above
10. Soundness test of cement by le-chatelier’s apparatus gives unsoundness due to :
a) Free lime only
b) Magnesia only
c) Both a) and b)
d) All of the above
11. The bulking of aggregate is due to :
a) Moisture content
b) Voids
c) Less compaction
d) All of the above
12. The tricalcium aluminates in cement has the property of :
a) Reacting fast with water
b) Causing initial setting of cement
c) Generating large amount of heat hydration
d) None of these
13. Water cement ratio is usually , expressed in :
a) Liter of water required per bag of cement
b) Liter of water required per kg of cement
c) Both a) and b)
d) None of these
D PRADAD
14. Pick up the incorrect statement from following :
a) Gypsum in cement decreases the setting time
b) The first component of cement which reacts with water is C2S
c) Bulking of sand is less when it’s particles are fine
d) All of the above
15. The increase in the strength of concrete with time is :
a) Linear
b) Non linear
c) Asymptotic
d) All of the above
16. The slump for beam slab is :
a) 75- 150 mm
b) 15- 30 mm
c) 50- 100 mm
d) All of the above
17. As the grade of concrete increase the quantity of cement required per cubic meter :
a) Increase
b) Decrease
c) Constant
d) All of the above
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3. 18. The inelastic behavior of concrete is due to the :
a) Shrinkage in concrete
b) Propagation of bound and mortar cracks
c) Presence of macro and micro cracks
d) All of the above
19. Quality control means :
a) Extra cost
b) A rational use of available resources
c) Adequate design to minimize cost
d) All of the above
20. The nature of fresh concrete is :
a) Elastic
b) Plastic
c) Rigid
d) All of the above
21. The concrete mixers are normally classified on the basis of :
a) The technique of discharging the mixed concrete
b) Capacity of batch handled
c) The no. of drums
d) All of the above
22. Steam curing is used in :
a) Columns only
b) Long slabs and column
c) Mass production of precast concrete
d) All of the above
23. Steam curing is not used with :
a) Ordinary Portland cement
b) High alumina cement
c) Rapid hardening cement
d) All of the above
24. Curing period is minimum for concrete using :
a) Ordinary Portland cement
b) High alumina cement
c) Rapid hardening cement
d) All of the above
25. The aggregate used for high strength concrete is :
a) Round aggregate
b) Irregular aggregate
c) Angular aggregates
d) All of the above
26. The ferro cement is a composite material obtained by :
a) Random dispose of short , discontinuous fibres in the convential concrete
b) Reinforcing the cement mortar with steel fibrous in the form of wire mesh
c) Blending ferrous compounds in the ordinary Portland cement
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4. d) All of the above
27. Plain cement concrete is strong in taking :
a) Tensile stress
b) Compressive stress
c) Shear stress
d) All of the above
28. The removal of excess air after placing concrete helps in increasing the strength of
concrete by :
a) 15 to 20 %
b) 20 to 30 %
c) 30 to 50 %
d) All of the above
29. Expansive cement expands mostly during it’s :
a) Initial hardening period
b) Final hardening period
c) Whole life
d) All of the above
30. Soundness of the material means the resistance of the material :
a) Moisture attack
b) Heat
c) Alternate freezing thawing
d) All of the above
31. The purpose of reinforcement in pestered concrete is :
a) To provide adequate bound stress
b) To resist tensile stress
c) To impart initial compressive stress in concrete
d) All of the above
32. Addition of pozzolana to cement :
a) Decrease workability
b) Increase strength
c) Increase heat of hydration
d) Decrease curing time
e) None of the above
33. Pick up the correct statement from following :
a) Segregation is necessary for a workable concrete
b) Consistency does not affect the workability of concrete
c) If the slump increase , workability decrease
d) If the concrete mix is dry , the slump is maximum
e) None of the above
34. Pick up the incorrect statement from following :
a) Space between the exterior walls of a ware house and bag piles should be 30 cm
b) Cement bags should preferably be piled on wooden planks
c) Cement bags should preferably be placed such that bags of one layers does not touch
the bags of the adjacent layers
d) Width and height of the pile should not exceed 3m and 2.7 m respectively
e) None of the above
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5. 35. Pick up the correct statement from following :
a) The free water is the amount of water added while mixing and the amount of water
held on the surface of the aggregates prior to mix
b) The total water is the free water and the amount actually absorbed by the aggregates
c) Both a) and b) of above
d) None of the above
36. Pick up the incorrect statement from following :
a) Admixtures accelerate hydration
b) Admixture make concrete water proff
c) Admixture make concrete acid proff
d) Admixture gives high strength
e) None of the above
37. Is sieve no. 10 mm and 4.75 mm are generally used for grading of :
a) Course aggregates
b) Fine aggregates
c) None of above
d) Both a) and b) above
38. When water cement ratio is increased , workability :
a) Increase
b) Decreases
c) Both a) and b) above
d) None of the above
39. The surface where two successive placements of concrete meet, is known as:
a) Construction joint
b) Expansion joint
c) Construction joint
d) Both a) and b) of above
40. Generally nominal mix is done by volume while design mix is done by :
a) Volume
b) Weight
c) Both a) and b) of above
d) Consolidation
41. Gel space ratio is defined as the ratio of :
a) Volume of hydrated cement to the sum of volume of hydrated cement and capillary
pores
b) The sum of volume of hydrated cement and capillary pores to volume of hydrated
cement
c) Both a) and b) of above
d) None of the above
42. Prestress is imparted to concrete by bearing in :
a) Pre tensioning
b) Post tensioning
c) Both a) and b) of above
d) None of the above
43. Choose the incorrect statement :
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6. a) Arrow representing activity in CPM network is drawn without any scale
b) Head of an activity represents the finish of an activity
c) Tail of an activity represents the start of an activity
d) None of the above
44.
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7. All the best
Answer:
1 B 11 A 21 B 31 C 41 B
2 B 12 D 22 A 32 C 42 A
3 A 13 A 23 C 33 E 43 B
4 C 14 A 24 B 34 E
5 A 15 B 25 C 35 E
6 A 16 A 26 B 36 D
7 B 17 C 27 B 37 E
8 C 18 A 28 B 38 B
9 B 19 B 29 B 39 A
10 A 20 B 30 B 40 C