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

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%

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

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

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

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

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

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

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%

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

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

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