Compaction is a process of expelling the entrapped air that goes between the molecules of the concrete. If we don?t expel this small bubbles of air, it will result into honeycombing and reduce the strength of the concrete layer. It has been recognized as a fact in the experimental studies that showed a 1% of air in the concrete approximately reduces its strength by 6%. The images bellow will help you see how this is all made in the actual construction field.

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