Engineering Questions with Answers - Multiple Choice Questions
Basic Civil Engineering MCQ’s – Tests on Stones
1 - Question
Which test is used to find the rate of wear of stones?
a) Crushing test
b) Abrasion test
c) Attrition test
d) Acid test
View Answer
Answer: c
Explanation: Crushing test is used to find crushing strength of stones. Abrasion test to find suitability of stone for road work. Acid test is used to find the quality of the stone.
2 - Question
In what solution is the stone sample placed in an Acid test?
a) HCl of strength .5%
b) H2SO4 of strength .5%
c) H2SO4 of strength 1%
d) HCl of strength 1%
View Answer
Answer: d
Explanation: As per the test procedure, the sample weighing about .5 – 1 N is placed in a solution of HCl for 7 days.
3 - Question
Which IS code gives details regarding the tests for weathering on building stones?
a) IS 1121 part 2
b) IS 1125
c) IS 1121 part 4
d) IS 1126
View Answer
Answer: b
Explanation: IS 1121 part 2 gives details about transverse strength, IS 1121 part 4 about shear strength and IS 1126 about the durability of building stones.
4 - Question
For crushing test what is the size of a specimen to be used?
a) 50 × 50 × 50mm
b) 100 × 100 × 100mm
c) 45 × 45 × 45mm
d) 40 × 40 × 40mm
View Answer
Answer: d
Explanation: As per the IS codes, 40 × 40 × 40 mm size cube of stone is to be used to perform the crushing test. The specimen is then placed in compression testing machine (CTM) and loaded at 14 N/mm2.
5 - Question
In abrasion test, what material is placed in addition to the specimen in the testing apparatus?
a) Metal piece
b) Stone piece smaller than specimen
c) Cast iron ball
d) Stainless steel ball
View Answer
Answer: c
Explanation: Abrasion test is used to check compatibility of stone with other material by allowing them to rub against each other, noting the wear resistance. Cast iron balls of 48 mm diameter are placed in the apparatus along with the specimen.
6 - Question
Which apparatus is used to test the hardness of stones?
a) Los Angeles
b) Deval’s
c) CTM
d) Dorry’s
View Answer
Answer: d
Explanation: Los Angeles is used for abrasion test, Deval’s for attrition and CTM for compression or crushing test.
7 - Question
Which stone has a hardness of 7 in the Mohr’s hardness scale?
a) Quartz
b) Calcite
c) Gypsum
d) Topaz
View Answer
Answer: a
Explanation: Mohr’s hardness scale ranks stones according to their hardness numbers. Calcite has a hardness of 3, gypsum 2 and topaz 8.
8 - Question
Why CaSO4 is not used in the crystallisation test?
a) Costly compound
b) Low solubility in water
c) Increases time taken for test
d) Releases toxic fumes
View Answer
Answer: b
Explanation: Crystallisation of CaSO4 in pores causes decay of stones and the low solubility in water prevent the use of this compound in the test.
9 - Question
Which of the below given formulas is used to calculate hardness coefficient?
a) (Final hardness / initial hardness) × 100%
b) 20 – (loss in weight / 2)
c) 20 – (loss in weight / 3)
d) ((20 – loss in weight) / 3) × 100%
View Answer
Answer: c
Explanation: The coefficient of hardness is expressed as a number and not a percentage.
10 - Question
What are the specifications for tamping rod used in impact test?
a) 16 mm steel rod with rounded end
b) 16 mm steel rod with square face
c) 16 mm copper rod with rounded end
d) 16 mm copper rod with square face
View Answer
Answer: a
Explanation: According to the IS code 2386, a 16 mm steel rod with rounded edge is used for tamping the sample filled inside the cylinder in three layers, 25 times each.
11 - Question
Why is attrition test performed?
a) To find resistance to scratch
b) To find resistance to weathering
c) To find resistance to wear
d) To find resistance to dressing
View Answer
Answer: c
Explanation: Attrition test is performed to test the rate of wear of stones that are used in road construction. It checks the rubbing against the same material of stone and is expressed in percentage.
12 - Question
What parameter is being checked for in freezing and thawing test?
a) Weathering
b) Durability
c) Water absorption
d) Texture
View Answer
Answer: b
Explanation: Durability refers to the resistance of stones to atmospheric conditions such as rain, heat, snow; temperature gradients; chemical impurities; cracks, creeks.