Which of the following has high tensile strength?
Plain hot rolled wires
Cold drawn wires
Heat treated rolled wires
All have same tensile strength
Correct Answer :
B. Cold drawn wires
Related Questions
Addition of pozzolana to ordinary port land cement, causes
Decrease in early strength
Reduction in chemical action with sulphates
Increase in shrinkage
All the above
The preliminary test is repeated if the difference of compressive strength of three test specimens, exceeds
5 kg/cm2
8 kg/cm2
10 kg/cm2
15 kg/cm2
The bulk density of aggregates does not depend upon:
Size and shape of aggregates
Specific gravity of aggregates
Grading of aggregates
Size and shape of the container
The main reinforcement in the heel of a T-shaped R.C. retaining wall is provided on
Top face perpendicular to wall
Bottom face perpendicular to wall
Both top and bottom faces perpendicular to wall
None of the above
A concrete using an air entrained cement
Has strength less than 10% to 15%
Has more resistance to weathering
Is more plastic and workable
Is free from segregation and bleeding
Setting time of cement increases by adding
Gypsum
Hydrogen peroxide
Calcium chloride
Sodium oxide
Inert material of a cement concrete mix, is
Water
Cement
Aggregate
None of these
Pick up the correct statement from the following:
The quality of water governs the strength of concrete
10% excess of water reduces the strength of concrete by 15%
30% excess of water reduces the strength of concrete by 50%
All the above
Tricalcium aluminate (C3A)
Reacts fast with water
Generates less heat of hydration
Causes initial setting and early strength of cement
Does not contribute to develop ultimate strength
In T-shaped R C. retaining walls, the main reinforcement in the stem is provided on
The front face in one direction
The front face in both directions
The inner face in one direction
The inner face in both directions
Pick up the correct statement from the following:
High percentage of C3S and low percentage of C2S cause rapid hardening
High percentage of C3S and low percentage of C2S make the cement less resistive to chemical attack
Low percentage of C3S and high percentage of C2S contribute to slow hardening
All the above
Vicat apparatus is used for
Fineness test
Consistency test
Test for setting time
Test for tensile strength
The design yield stress of steel according to IS: 4561978 is: (Where fy is the characteristic yield strength of steel)
0.37 fy
0.57 fy
0.67 fy
0.87 fy
A higher modular ratio shows
Higher compressive strength of concrete
Lower compressive strength of concrete
Higher tensile strength of steel
Lower tensile strength of steel
Water required per bag of cement, is
7 kg
14 kg
21 kg
35 kg
High temperature
Increases the strength of concrete
Decreases the strength of concrete
Has no effect on the strength of concrete
None of these
If the storey height is equal to length of RCC wall, the percentage increase in strength is
0
10
20
30
The produce impermeable concrete
Thorough mixing of concrete is required
Proper compaction of concrete is required
Proper curing of concrete is required
All the above
For quality control of Portland cement, the test essentially done is
Setting time
Tensile strength
Consistency
All the above
Sand generally contains salt if it is obtained from:
Nala beds
River beds
Sea beds
None of these
The property of fresh concrete, in which the water in the mix tends to rise to the surface while placing and compacting, is called
Segregation
Bleeding
Bulking
Creep
Pick up the correct statement from the following:
Water enables chemical reaction to take place with cement
Water lubricates the mixture of gravel, sand and cement
Strength of concrete structure largely depends upon its workability
All the above
When shear stress exceeds the permissible limit in a slab, then it is reduced by
Increasing the depth
Providing shear reinforcement
Using high strength steel
Using thinner bars but more in number
For a continuous slab of 3 m × 3.5 m size, the minimum overall depth of slab to satisfy vertical deflection limits is
50 mm
75 mm
100 mm
120 mm
Addition of pozzolana to cement
Decreases workability
Increases strength
Increases heat of hydration
None of these
Log Angles machine is used to test the aggregate for
Crushing strength
Impact value
Abrasion resistance
Water absorption
Transport of concrete by pumps, is done for a distance of
100 m
200 m
300 m
400 m
Di-calcium silicate (C2S)
Hydrates rapidly
Generates less heat of hydration
Hardens rapidly
Provides less ultimate strength to cement
Saw dust can be rendered chemically inert by boiling it in water containing
Ferrous sulphate
Potassium chloride
Ammonia
Nitric acid
Which of the following losses of pre-stress occurs only in pretensioning and not in post-tensioning?
Elastic shortening of concrete
Shrinkage of concrete
Creep of concrete
Loss due to friction