To obtain cement dry powder, lime stones and shales or their slurry, is burnt in a rotary kiln at a temperature between
1100° and 1200°C
1200° and 1300°C
1300° and 1400°C
1400° and 1500°C
Correct Answer :
D. 1400° and 1500°C
Related Questions
According to IS: 4561978, the flexural strength of concrete is
Directly proportional to compressive strength
Inversely proportional to compressive strength
Directly proportional to square root of compressive strength
Inversely proportional to square root of compressive strength
Di-calcium silicate (C2S)
Hydrates rapidly
Generates less heat of hydration
Hardens rapidly
Provides less ultimate strength to cement
Which of the following statements is incorrect?
Minimum cross sectional area of longitudinal reinforcement in a column is 0.8%
Spacing of longitudinal bars measured along the periphery of column should not exceed 300 mm
Reinforcing bars in a column should not be less than 12 mm in diameter
The number of longitudinal bars provided in a circular column should not be less than four
Which of the following has high tensile strength?
Plain hot rolled wires
Cold drawn wires
Heat treated rolled wires
All have same tensile strength
Separation of coarse aggregates from mortar during transportation, is known
Bleeding
Creeping
Segregation
Shrinkage
Maximum distance between expansion joints in structures as per IS: 456 1978 is
20 m
30 m
45 m
60 m
Pick up the correct statement from the following:
According to the petrological characteristics, concrete aggregates are classified as heavy weight, normal weight and light weight
According to the shape of the particles, concrete aggregates are classified as rounded irregular, angular and flaky
According to the surface texture of the particles, the concrete aggregates are classified as glassy, smooth, granular, rough, crystalline, honey combed and porous
All the above
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
For quality control of Portland cement, the test essentially done is
Setting time
Tensile strength
Consistency
All the above
Under normal conditions using an ordinary cement, the period of removal of the form work, is:
7 days for beam soffits
14 days for bottom slabs of spans 4.6 m and more
21 days for bottom beams over 6 m spans
All the above
High carbon content in the steel causes
Decrease in tensile strength but increase in ductility
Increase in tensile strength but decrease in ductility
Decrease in both tensile strength and ductility
Increase in both tensile strength and ductility
For given water content, workability decreases if the concrete aggregates contain an excess of
Thin particles
Flat particles
Elongated particles
All the above
If 1500 g of water is required to have a cement paste 1875 g of normal consistency, the percentage of water is,
20 %
25 %
30 %
35 %
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
To determine the modulus of rupture, the size of test specimen used is
150 × 150 × 500 mm
100 × 100 × 700 mm
150 × 150 × 700 mm
100 × 100 × 500 mm
In a counterfort retaining wall, the main reinforcement in the stem at mid span is provided on
Front face only
Inner face only
Both front face and inner face
None of the above
Pick up the incorrect statement from the following:
Space between the exterior walls of a warehouse and bag piles should be 30 cm
Cement bags should preferably be piled on wooden planks
Width and height of the pile should not exceed 3 m and 2.70 m respectively
None of these
Strength of concrete with passage of time
Increases
Decreases
Fluctuates
Remains constant
Normally pre-stressing wires are arranged in the
Upper part of the beam
Lower part of the beam
Center
Anywhere
The process of hardening the concrete by keeping its surface moist is known
Placing
Wetting
Curing
Compacting
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
Poisson's ratio for concrete
Remains constant
Increases with richer mixes
Decreases with richer mixes
None of the above
Pick up the incorrect statement from the following:
With passage of time, the strength of cement increases
With passage of time, the strength of cement decreases
After a period of 24 months, the strength of cement reduces to 50%
The concrete made with storage deteriorated cement, gains strength with time
In counterfort type retaining walls (i) The vertical slab is designed as a continuous slab (ii) The heel slab is designed as a continuous slab (iii) The vertical slab is designed as a cantilever (iv) The heel slab is designed as a cantilever The correct answer is
(i) and (ii)
(i)and(iv)
(ii) and (iii)
(iii) and (iv)
Approximate value of shrinkage strain in concrete, is
0.003
0.0003
0.00003
0.03
Proper batching ensures
Economy
Durability
Workability
All the above
The aggregate impact value of the aggregate used in
Building concrete is less than 45
Road pavement concrete is less than 30
Runway concrete is less than 30
All the above
For a simply supported beam of span 15 m, the minimum effective depth to satisfy the vertical deflection limits should be
600 mm
750 mm
900 mm
More than 1 m
The slab is designed as one way if the ratio of long span to short span is
Less than 1
Between 1 and 1.5
Between 1.5 and 2
Greater than 2
Pick up the incorrect statement from the following:
The bottom and top ends of slump mould are parallel to each other
The axis of the mould is perpendicular to the end faces
The internal surface of the mould is kept clean and free from set cement
The mould is in the form of a frustum of hexagonal pyramid