Building Material and Construction 312338 Practical No 5 Manual Answer

Practical Significance-

Bricks are the basic building blocks of masonry work and construction. Field tests like dropping, striking, and scratching on a given sample of brick provide practical outcomes related to strength, durability, surface hardness, quality control, and material suitability. These outcomes guide construction decisions and contribute to the overall success and longevity of the built structure.

Relevant Theoretical Background-

1. Dropping Test -When bricks are dropped from the height of 1 to 1.2m (4 feet), they should not crack or break. This ensures the durability and quality of bricks.

2. Striking Test-For struck test, take 2 bricks and strike each other along the longer edge. If it produces a metallic or Ring bell sound, the bricks are quality.

3. Scratching Test- When bricks are scratched by an iron nail it must produce any impressions on the surface, these bricks are quality.

Procedure

1. Conduct the visit to Perform a field test on bricks.

2. Students should select the bricks and conduct the tests such as dropping, striking, and

scratching.

3. Students should observe the bricks and the action of dropping, striking, and scratching.

4. Identify the properties of brick.

Observation Table

Sr.No.	Test	Size of Brick	Observation
1	Dropping	(190 x 90 x 90 mm)	The brick broke into several smaller pieces.
2	Striking	(190 x 90 x 90 mm)	A small chip formed on the edge of the brick.
3	Scratching by nail	(190 x 90 x 90 mm)	Shallow scratch visible.

Result

In all three tests, the bricks showed some level of damage, indicating they are not completely resistant to impacts, strikes, or scratches.

Interpretation of results

In conclusion, the findings underscore the significance of meticulously choosing brick varieties depending on their intended use and taking into account factors such as impact resistance, strength uniformity, and scratch resistance.

Practical Related Questions

1. Write the standard Size of bricks

Answer:

The standard size of masonry bricks is 19 cm x 9 cm x 9 cm.
The nominal size of masonry bricks (with mortar) is 20 cm x 10 cm x 10 cm.
The traditional size of masonry bricks is 23 cm x 11.4 cm x 7.6 cm.

2. Write the Use of First-class bricks.

Answer:

(a) Brick ballast in R.C.C
(b) Boundary walls
(c) Low height walls
(d) Pavements

3. State the function of second-class bricks.

Answer:

It is also a good, strong, and durable brick with a uniform yellowish-red color. It is commonly used for inner walls with a coating or plaster. The compressive strength of a second-class brick is 7.5 N/mm² or 75 kg/cm². After being submerged in water for 24 hours, it typically absorbs around 18 to 20% of its dry weight.

4. State the water absorption capacity of first-class brick.

Answer:

The brick's water absorption should range from 12-15% of its dry weight after being submerged in cold water for 24 hours, and its crushing strength should be at least 10 N/mm2.

5. Compare the compressive strength of brick.

Answer:

Type of Brick	Average Compressive Strength (MPa)	Applications
First Class Burnt Clay Brick	20-35	Load-bearing walls, columns, foundations, chimneys
Second Class Burnt Clay Brick	15-25	Non-load bearing walls, internal walls, partitions
Fly Ash Brick	10-20	Non-load bearing walls, partitions, insulation purposes
Concrete Brick	20-40	Load-bearing walls, foundations, pavements, retaining walls