1. For a good building stone how much is the required crushing strength?
a) Less than 50 N/mm2
b) Greater than 100 N/mm2
c) 155 N/mm2
d) 10 N/mm2
Discussion
Explanation: Crushing strength or compressive strength of a stone is the load per unit area at which the stone starts cracking. It should be greater than 100 N/mm2 to ensure sufficient strength for use in construction.
2. Which of the following is a good fire-resistant stone?
a) Clay
b) Granite
c) Quartz
d) Limestone
Discussion
Explanation: Granite and Quartz undergo sudden expansion and flies into splinters. Limestone gets easily crumbled. Clay can withstand higher temperature and is used in pizza ovens, fireplaces, etc.
3. What is a freestone?
a) Stone free from impurities
b) Stone that doesn’t require dressing
c) Metamorphic stone
d) Stone free from veins and planes of cleavage
Discussion
Explanation: For the ease of quarrying a stone must be soft, compact-grained, homogeneous, free from veins and planes of cleavage.
4. Why are stones with lighter shades of colour preferred?
a) Easy to clean
b) Easily available
c) Don’t spoil the appearance
d) Darker shades are heavier
Discussion
Explanation: Even if the stone fades a little bit it will not show a striking difference and doesn’t spoil the look of it. They don’t need to be painted or maintained much compared to darker shades.
5. Hardness is an important parameter considered in the construction of:
a) Slabs
b) Walls
c) Bridges
d) Arches
Discussion
Explanation: It’s required in structures subjected to heavy loading. Bridge is one such structure. Slabs, walls and arches are not subjected to heavy loadings as a bridge.
6. What is the required specific gravity for a good building stone?
a) Greater than 2.7
b) Less than 3
c) Greater than 3
d) Less than 2.7
Discussion
Explanation: As per IS standards. Heavy stones are used in the construction of abutments, dams, docks. Lighter ones are used in building construction.
7. The percentage absorption by weight of a good stone, after how many hours should not exceed .6?
a) 6 hrs
b) 12 hrs
c) 48 hrs
d) 24 hrs
Discussion
Explanation: As per IS standards, 24 hrs is the time a stone has to be immersed in water to check for water absorption. Time less or more than this would not result in providing the appropriate data.
8. What texture should a building stone possess?
a) Loose grains
b) Crystalline structure
c) Cavities
d) Cracks
Discussion
Explanation: Texture is the grains composing the stone in the strata. Crystalline structure is the required texture. Other options are undesired textures.
9. Seasoning is required for stones.
a) True
b) False
Discussion
Explanation: A stone should be properly dried before using for structural works. The sap contained in freshly quarried stones will make them soft and lead to decay eventually.
10. A percentage wear of 3% indicates a good stone.
a) True
b) False
Discussion
Explanation: A percentage wear of less than 3% indicates a non-satisfactory stone. A percentage wear of 3% indicates a tolerable stone and greater than 3% indicates a good quality stone.