Construction joints are generally provided in concrete
Roads
Retaining walls
Lining of canals
All the above
Correct Answer :
D. All the above
Related Questions
Sands of zone I are:
Course
Medium
Medium to fine
Fine
The critical section for finding maximum bending moment for footing under masonry wall is located
At the middle of the wall
At the edge of the wall
Halfway between the middle and edge of the wall
At a distance equal to effective depth of footing from the edge of the wall
The light weight aggregates are obtained from
Sedimentary rocks
Metamorphic rocks
Igneous rocks
Volcanic source
The top diameter, bottom diameter and the height of a slump mould are:
10 cm, 20 cm, 30 cm
10 cm, 30 cm, 20 cm
20 cm, 10 cm, 30 cm
20 cm, 30 cm, 10 cm
Wp and Wf are the weights of a cylinder containing partially compacted and fully compacted concrete. If the compaction factor (Wp/Wf) is 0.95, the workability of concrete is
Extremely low
Very low
Low
High
Water cement ratio is
Volume of water to that of cement
Weight of water to that of cement
Weight of concrete to that of water
Both (a) and (b) of the above
Increase in the moisture content in concrete
Reduces the strength
Increases the strength
Does not change the strength
All of the above
Inert material of a cement concrete mix, is
Water
Cement
Aggregate
None of these
According to the recommendations of IS : 456-1978, the expansion joints
Are provided where plane changes abruptly
Are provided to ensure minimum resistance
Do not carry reinforcement across them
All the above
The diameter of the Vicat plunger is 10 mm and its length varies from
20 mm to 30 mm
30 mm to 40 mm
40 mm to 50 mm
50 mm to 60 mm
Concrete containing
Siliceous aggregates, has higher co-efficient of expansion
Igneous aggregates, has intermediate coefficient of expansion
Lime stones, has lowest co-efficient of expansion
All the above
The main reason for providing number of reinforcing bars at a support in a simply supported beam is to resist in that zone
Compressive stress
Shear stress
Bond stress
Tensile stress
The high strength of rapid hardening cement at early stage, is due to its
Finer grinding
Burning at high temperature
Increased lime cement
Higher content of tricalcium
Percentage of pozzolanic material containing clay upto 80% used for the manufacture of pozzolana cement, is
30 %
40 %
50 %
60 %
According to IS: 4561978, the maximum reinforcement in a column is
2 %
4 %
6 %
8 %
Internal friction between the ingredients of concrete, is decreased by using
Less water
Fine aggregates
Rich mix
More water and coarse aggregates
Specified compressive strength of concrete is obtained from cube tests at the end of
3 days
7 days
21 days
28 days
Hydration of cement is due to chemical action of water with
Tricalcium silicate and dicalcium silicate
Dicalcium silicate and tricalcium aluminate
Tricalcium aluminate and tricalcium alumino ferrite
All the above
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
If the slump of a concrete mix is 60 mm, its workability is
Very low
Low
Medium
High
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
Ordinary Portland cement is manufactured from
Lime stone and clay
Gypsum and lime
Pozzolana
Lime, pozzolana and clay
The ratio of the length to breadth of a wooden float, is
4.5
5.5
6.5
7.5
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
Workability of concrete is inversely proportional to
Time of transit
Water-cement ratio
The air in the mix
Size of aggregate
Pick up the incorrect statement from the following:
Concrete for which preliminary tests are conducted, is called controlled concrete
Bulking of sand depends upon the fineness of grains
Concrete mix 1 : 6 : 12, is used for mass concrete in piers
All the above
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
10 %
12 %
15 %
25 %
For an ordinary Portland cement
Residual does not exceed 10% when sieved through IS Sieve No. 9
Soundness varies from 5 to 10 mm
Initial setting time is not less than 30 minutes
Compressive stress after 7 days, is not less than 175 kg/cm2
According to IS : 382-1963, a good aggregate should be
Chemically inert
Sufficiently strong
Hard and durable
All the above
Workability improved by adding
Air-entraining agent
Foaming agent
Oily-agent
All the above