The glass articles, after manufactured, are to be cooled down slowly and gradually. The process of slow and homogeneous cooling of glass articles is known as
- Annealing
- Blowing
- Rolling
- Spinning
Loss of strength of cement stored in bags in godowns for 3 months is about
- 30%
- 50%
- 15%
- 0%
While testing the compressive strength of cement concrete, the correct standard conditions (viz temperature, age, humidity and size of the specimen) to be maintained as per IS are
- 27 ± 3°C, 28 days, 90% and 15 cm cube
- 26 ± 2°C, 28 days, 80% and 15 cm cube
- 25 ± 1°C, 14 days, 75% and 10 cm cube
- 27 ± 3°C, 7 days, 70% and 10 cm cube
On Mohs scale, a scratch with the aid of a finger nail indicates a hardness in the range of
- 0-1
- 1-2
- 2-3
- 3-4
Plastic materials that exhibit excellent fatigue resistance is/are
- PVC & CPVC
- HDPE & LDPE
- SIP
- ABS
Percentage of water absorption in a good quality of building stone should be
- 0 – 5%
- 10 – 15%
- 15 – 20%
- 20 – 25%
_______________ are used to finish concrete surfaces such as bridge floors, road slabs, station platforms etc.
- Immersion vibrators
- Surface vibrators
- Form vibrators
- Internal vibrators
There is initial ____________________ of cement concrete which is mainly due to loss of water through forms, absorption by surfaces of forms, etc.
- Swelling
- Cracking
- Shrinkage
- Dispersion
The wood preservative Creosote is derived from
- wood or coal
- acidic cupric chromate
- chromatid zinc chloride
- pentachlorophenol
How much is the Carbon content (%) in Cast Iron?
- 2 – 4
- 0.15 – 1.5
- 0.3 – 0.5
- None of the above
Specific Gravity of Fly Ash is in the range of
- 2.1 to 3.0
- 3.1 to 4.0
- 4.1 to 5.0
- 5.1 to 6.0
The pigment used in paints for corrosive resistance is
- red lead
- white lead
- gypsum
- ferrous oxide
The approximate calcium oxide composition limits of ordinary portland cement is
- 60 – 67%
- 17 – 25%
- 3 – 8%
- 0.1 – 4%
The approximate % of calcium oxide in fat lime is
- 90 – 95%
- 80 – 85%
- 75 – 80%
- 70 – 75%
Indentations on the bricks provided to form a key for holding the mortar is called as
- Bond
- Course
- Frog
- Quoins
__________________ is the ability of a material to resist deterioration over long period of time.
- Toughness
- Hardness
- Durability
- Ductility
Following compounds can be used as accelerators except
- CaCl2
- CaSO4
- NaCl
- Na2SO4
Which of the following is incorrectly matched ?
- Grade 43 cement – Used in plastering and flooring
- Grade 33 cement – Used in RCC work of multi-storey building
- Grade 53 cement – compressive strength is 53 N/mm3 (28 days)
- Portland puzzolana cement (PPC) – used in mass concrete and marine structure
Concrete mix proportioning guidelines are given by
- IS 875(Part-1)-1987
- IS 456-2000
- IS 10262-2009
- IS 800-2007
The expansion and shrinkage of plywoods are comparatively very low as
- they are held in position by adhesives
- they are glued under pressure
- plies are placed at right angles to each other
- they are prepared from veneers
