You can check the quality of the solid concrete blocks on site by following some simple methods as given below.
- Drop test. Randomly select one block from the total no.
- Corner test.
- Chisel test.
- Nail test.
- Texture.
- Shape & size.
How do you measure the strength of concrete blocks?
The compressive strength of a concrete masonry unit shall be taken as the maximum load in Newtones divided by the gross cross sectional area of the unit in square millimeters. Report to the nearest 0.1 N/mm2 separately for each unit and the average for the 8 full units.
What is the compressive strength of concrete blocks?
For normal, medium weight concrete block, load- bearing, hollow or solid, their compressive strength is about 12.5N/mm2 or 125kg/cm2. For denser, higher weight concrete block, load- bearing, hollow or solid, their compressive strength is about 17.5N/mm2 or 175kg/cm2.
What are the properties of concrete hollow blocks?
Properties of Hollow Concrete Blocks
- Moisture Movement: Not more than 0.09%
- Water Absorption: Not more than 10%
- Drying Shrinkage: Not more than 0.06%
- Compressive Strength: For Grade A: 3.5 to 15.0 N/mm. For Grade B: 3.5 and 5.0 N/mm.
- Density:
Are there different grades of concrete blocks?
Hollow concrete blocks come in three grades: Grade A has a minimum density of 1,500 kg/m3. Grade B has a density of less than 1,500 kg/m3. Grade C has a density greater than 1,000 kg/m3.
What is the minimum amount of specimen subjected for quality test of concrete hollow blocks?
Six (6) specimens to be submitted for one (1) quality test in which three (3) specimens for Compression Test and the remaining three (3) for Moisture Content and Water Absorption.
What is the density of concrete blocks?
Concrete @ your Fingertips Aggregate blocks come in two types. Dense aggregate blocks have a density in the range 1800 – 2100 kg/m3, while lightweight aggregate blocks (otherwise known as Medium Dense) have with a density in the range 650 – 1500 kg/m3. Aircrete blocks have a density in the range 400 – 900 kg/m3.
What are the tests for concrete?
Most Common Quality Tests on Fresh concrete are:
- Workability Tests. Workability of concrete mixture is measured by, Vee-bee consistometer test, Compaction factor Test, and Slump test.
- Air content. Ad.
- Setting Time. The action of changing mixed cement from a fluid state to a solid state is called “Setting of Cement”.
What is the density of hollow block?
Hollow Blocks
| Size (mm) | Weight(Kg) | Density (Kg / M3) |
|---|---|---|
| 400 x 200 x 200 | 22 | 2100 |
| 400 x 200 x 250 | 26 | 2100 |
| 400 x 200 x 300 | 30 | 2100 |
| 390 x 190 x 90 | 13 | 2100 |
What is the mixture for concrete blocks?
Concrete blocks are often made of 1:3:6 concrete with a maximum size aggregate of 10mm or a cement-sand mixture with a ratio of 1:7, 1:8 or 1:9. These mixtures, if properly cured, give concrete blocks a compression strength well above what is required in a one-storey building.
What are the properties of a hollow concrete block?
Hollow concrete blocks have good insulating properties against sound, heat and dampness. 13. These blocks have low water absorption than conventional bricks. If you want to know how to measure water absorption in bricks then read the water absorption test of bricks.
What is the grading for sand used in hollow concrete block?
Normal weight blocks are made with cement, sand, gravel, crushed stone and air-cooled slag. The grading for sand used in Hollow concrete block shall be as given below: The aggregates for solid blocks shall be sand as per IS : 383-1970 and well graded aggregate of suitable maximum size as per the dimensions of the block.
How to test compressive strength of concrete masonry blocks?
Compressive Strength Tests on Concrete Masonry Blocks Eight blocks are taken to determine the average compressive strength of concrete masonry block. The blocks should be tested with in 3days after collected in lab. The age of each block shall be 28 days.
How to check if a block is hollow or hollow?
Blocks of same mix shall be taken and divide them as follows to conduct the following tests. All blocks should be checked in this step. The length, width and height are measured with steel scale. If it is a hollow block, then the web thickness and face shell are measured with caliper ruler.
