Laboratory Tests and Field Checks on Bricks

Bricks are a fundamental building material which is essential for constructing durable and structurally sound structures. However, not all bricks are created equal; their quality varies, impacting the integrity and long-life of constructions. To ensure the suitability of bricks for construction purposes, various laboratory tests and field checks are conducted. Here we will discuss the significance of these assessments, detailing procedures, parameters, and acceptable thresholds.

 

I. Laboratory Tests

 

Crushing Strength

 

Procedure:

1. Preparation: Immerse brick specimens in water for 24 hours, fill the frog with 1:3 cement mortar, and store in damp conditions.

2. Testing: Place specimens in a compression testing machine, apply axial load at a uniform rate of 14 N/mm².

3. Measurement: Note the crushing load and calculate crushing strength by dividing the load by the loaded area.

4. Average: Determine the average crushing strength from five specimens.

 

Absorption Test

 

Procedure:

1. Initial Weighing: Weigh dry brick specimens.

2. Immersion: Immerse specimens in water for 24 hours, then wipe and weigh them in wet condition.

3. Calculation: Calculate percentage absorption as the ratio of water absorbed to dry weight multiplied by 100.

4. Average: Calculate the average absorption from five specimens, ensuring it does not exceed 20%.

 

Field Tests

 

Uniformity in Size

 

Procedure: Observe the rectangular plane surface and ensure uniformity in size.

 

Uniformity in Colour

 

Procedure: Ensure uniform color throughout the brick before purchasing.

 

Structure

 

Procedure: Break a few bricks and observe cross-sections for homogeneity, compactness, and absence of defects like holes and lumps.

 

Sound Test

 

Procedure: Strike two bricks together and ensure they produce a clear ringing sound, indicating quality.

 

Hardness Test

 

Procedure: Scratch the brick with a nail; if no impression is marked, the brick is sufficiently hard.

 

Efflorescence Test

 

Procedure:

1. Preparation: Place brick specimens in a glass dish with water to a depth of 25 mm in a well-ventilated room.

2. Observation: After evaporation, observe for white/grey patches.

3. Reporting: Report observations as nil, slight, moderate, heavy, or serious, indicating the presence and severity of deposits.

 

 

Selection of best bricks for construction involves a combination of laboratory tests and field checks. These results makes sure that bricks meets required standards of strength, absorption, uniformity, and absence of defects. By applying given procedures procedures and methods, engineers can confidently select bricks that guarantee the structural integrity and safety of their constructions.