Building Material (Part-II) (GENERAL ENGINEERING) (SSC JE)

Total Questions: 50

31. The vehicle used in bronze paints is usually [BPSC AE (GEN. ENGG.)-29.03.2019 ]

Correct Answer: (d) nitrocellulose lacquer
Solution:Bronze points–Bronze points are reflective paints that are widely used on radiators. It can be used either for internal or external metal structure. General vehicle used in bronze paint is "nitrocellulose lacquer".

Pigments used are aluminium bronze or copper bronze.

Vehicle/Binder–Holds the constituent of paint and spread over surface.

• If forms the body of the paint

• Linseed oil is the most widely used as vehicle.

32. The number of vertical joints in a stretcher course is x times the number of joints in the header course, where x is equal to [BPSC AE (GEN. ENGG.)-29.03.2019]

Correct Answer: (a) 1/2
Solution:Header–This is a brick laid with its breadth or width parallel to the face or front or direction of wall. The course containing headers is called course.

Stretcher–This is a brick laid with its length parallel to the face or front or direction of a wall. The course containing is called a stretcher course.

33. The amount of water used for 1 kg of distemper is [BPSC AE (GEN. ENGG.)-29.03.2019 ]

Correct Answer: (c) 0.6 liter
Solution:Distempers–The distemper is made by mixing a dry pigment (chalk powder or whiting) with clean water and ordinary size.

• It is used on plastered surface not exposed to weather.

• This is used as interior paint for homes. • Distemper are washed away when used in exposed surfaces.

• Normally, 500 to 700 ml water is required for 1kg of distemper. Hence we can take 0.6 litre of water for 1kg of distemper.

34. What is used to make paints odourless to some extent? [BPSC AE (GEN. ENGG.)-29.03.2019 ]

Correct Answer: (d) Plioway resins
Solution:Plioway resins– This is the substance used to make points odourless to some extent.

• It eliminates the odour that is normally present in the alkyd stain blocking primers.

• It aims at reducing the volatile organic compound (VOC) content which is harmful.

Advantages–

• Soluble in low odour solvents.

• Forms tough, durable films.

• Excellent adhesion to a wide variety of substrates.

• Barrier properties against water and carbon dioxide.

35. In Ordinary Portland cement the percentage of lime constitutes : [MPSC AE PRE. 23.06.2019 ]

Correct Answer: (a) 60 to 67
Solution:Chemical composition of portland cement–
OxidesFunctionComposition (%)
CaO (Lime)Controls strength and soundness; its deficiency reduces strength and setting time60–65
SiO₂ (Silica)Gives strength; excess causes slow setting17–25
Al₂O₃ (Alumina)Responsible for quick setting; if in excess, it lowers the strength3–8
Fe₂O₃ (Iron Oxides)Gives colour and hardness; if in excess, it causes cracks in mortar and concrete and makes it unsound5–4
CaSO₄Retarder2–5
SO₃ (Sulphur Trioxide)Soundness1–3%

36. Seasoning of timber is required to– [RRB JE 26.08.2015 (Shift-III) RRB S.S.E (Bilaspur/Secunderabad) 21.12.2014]

Correct Answer: (d) Remove sap from the timber
Solution:Seasoning of timber:- The newly cutted trees have water in large quantity in sap and minimum in this inner part of wood.

• We remove sap of the wood, then do seasoning for drying the wood and making for structural use

• By drying the timber we make its strength high more elastic and durable.

• A well seasoned timber has 15% moisture content in it.

(I) Natural seasoning

(II) Artificial seasoning

37. Which of the following timbers is suitable for making sports goods? [RRB JE 26.08.2015 (Shift-III) BPSC AE (GEN. ENGG.) 14.10.2022]

Correct Answer: (a) Mulberry
Solution:Mulberry is a strong tough and elastic wood, it takes up a clean finish. It can be well seasoned. It is turned and curved easily. Mulberry is typically used for baskets and sports good like hockey, tennis, rackets and cricket bats etc.

 Mahogany–Mahogany wood has a beautiful reddish color and straight grains. It is used for furniture, chests and make a musical instruments.

Sal–It is less expensive when compared with the teak. The fruits of the sal tree are used in the treatment of expensive salivation, epilepsy and chlorosis.

• Polish not required but pointing is required

Deodar–It is in great demand as building material because of its durability not resistant character and fine close grain.

38. Which of the following trees yields hard wood? [RRB JE 26.08.2015 (Shift-I)]

Correct Answer: (c) Shishum
Solution:Hard wood : It is dark in colour.

• It's growth are slower and heavier in weight.

• It's annual rings are indistinct and strength is strong along and across the grains.

• Examples are – Teak, Sal, shishum and other deciduous trees.

39. Initial setting time is maximum for– [RRB JE 26.08.2015 (Shift-II)]

Correct Answer: (c) Low heat portland-pozzolana cement
Solution:
Type of cementInitial setting time
OPC30 min.
Portland pozzolana cement30 min.
Portland slag cement30 min.
Low heat cement60 min.
Rapid hardening cement30 min.

40. The main ingredients of portland cement are– [RRB JE 26.08.2015 (Shift-II)]

Correct Answer: (a) Lime and silica
Solution:Ingredient of cement–