QualityTests and Experiments on Concrete

Mostly concrete structures are failed due to poor workmanship which is a very tricky factor to control. Structures build with concrete has a life both from serviceability point of view and from structural point of view and this life depends solely on the quality of the material while placing.
The quality of concrete is tested by using following experiments and tests :-

1. Workability or consistency 

Possible tests for workability or consistency include :-

a. Slump test by means of the standard ASTM code. The slump in inches recorded in the mixture indicates its workability
b. Remolding tests using Powers’ flow table.
c. Kelly’s ball apparatus

2. Air Content

 Measurement of the air content in fresh concrete is always necessary, especially when air entraining agents are used.

3. Compressive Strength of Concrete

This is done by loading cylinders 6 in. in diameter and 12 in. high in compression perpendicular to the axis of the cylinder. For high-strength concrete, cylinders 4 in. dia. X 8 in. – height can be used applying proper dimensional correction.

4. Flexural strength of Plain Concrete Beams :-

This test is performed by three-point  loading of plain concrete beams of size 6 in. x 6 in. x 18 in. that have spans three times their depth.

5. Tensile Splitting Tests

These tests are performed by loading the standard cylinder by a line load perpendicular to its longitudinal axis with the cylinder placed horizontally on the testing machine pattern.