Internal vibrators, sometimes referred to as “spud” or “porker” vibrators are the most common tools used to achieve concrete consolidation in foundations, columns and walls.

In addition to consolidating freshly placed concrete and ensuring concrete completely flows into corners of the formwork and around reinforcement, vibrators blend different concrete lifts together into a single solid mass of concrete and minimize surface voids (bug holes) and lift lines on exposed concrete surfaces.

When concrete is first placed into forms, it is honeycombed or contains up to 20% by volume of entrapped air bubbles created by the mixing and placing operations. These entrapped air bubbles are the “bad” air bubbles that must be removed by proper vibration to achieve maximum concrete density or good concrete.During the process of removing the “bad” air, proper placing and vibration techniques will also minimize lift or placement lines and surface voids.