How long should concrete be vibrated in different construction situations?

The vibration time at each point depends on the type of concrete, vibrator size, and other factors. This vibrating time can range from 5 to 15 seconds. The time is shorter for more fluid consistencies, as excessive vibration in these mixtures can lead to segregation. Over-vibration could lead to disintegration.

Concrete is considered well-vibrated when the surface becomes compact and shiny, and no more air bubbles emerge. There is also a noticeable change in the noise produced by the vibrator. Many structural defects result from hasty and disorderly concrete vibration.