How to Test Brick Quality

ClayMineAdobe.com - Test of Strength
ClayMineAdobe.com - Test of Strength

There are seven tests in order to test the quality of your bricks. Half of the tests are done in lab and the later are done on site.
- Compressive Test of Strength: This test measures the compressive strength of the brick. Usually five bricks from one batch are taken into the lab to have the test preformed. The test is a crushing machine which finds the pressure that is the bricks breaking point. Once that pressure is accounted for they take the average of the five bricks breaking points to find the accumulated brick strength.
- Water Test of Absorption: This test is conducted by first weighing bricks that are completely dry. Then those same bricks are soaked in water for over twenty four hours. After twenty four hours the bricks are then taken out of the water and weighed. The difference found in weight between the dry vs wet brick is its absorption rate. The percentage of water absorbed is recorded and a good brick usually does not absorb more then twenty percent of its weight.

ClayMineAdobe.com - The Test of Shape
ClayMineAdobe.com -
The Test of Shape
- The Test of Efflorescence: When brick absorbs moisture it can sometimes form a white or gray outer layer. This means their is a presence of harmful alkalies with in the brick. So each brick must be tested for this harmful substance. They test for this by placing a brick underwater for twenty four hours. After twenty four hours the brick is then placed outside in the shade to dry. If a layer does not form then the brick is alkalis free. There is only a ten percent acceptability of a white layer forming on the brick. If the alkalis layer covers more than fifty percent of the brick - then the brick batch is no good.
- Test of Hardness: This test is to show how scratch able and damage able a brick is. Durability of the brick is tested by scratching the bricks surface. If it stays in tact then the brick is made of a good quality.
- The Test of Shape, Size and Color: It takes twenty bricks to preform this test. Within this test the bricks are staked side by side and measured for their average length, width and height. They all must meet the set standards. They are after ward checked for sharpness of edges, and uniformness. Bricks of good quality usually are a bright shade of red with uniform measurements.
- Test of Sound: This test is preformed by striking two bricks against each other. If they give off a ringing sound and do not break during the process then they are considered good quality.
- Test of Structure: This is a test which involves observing the brick in a broken down state. The inspectors are searching for any cracks/holes or flows that could present a problem and cause the brick to be of lower quality.