Types Of Vibrators Used In Construction | Concrete Vibrators

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In the world of construction, vibrators play a crucial role in compacting concrete, ensuring sturdy structures like roads, trains, and buildings. Let’s dive into the basics of what vibrators are and their types.

What is a Vibrator?

Concrete vibrators come in various shapes and sizes, ranging from smaller battery-powered ones to larger electrically powered ones. When these vibrators are in action, they reduce internal friction between concrete particles through oscillation, resulting in a dense and compact concrete mass.

Purpose of Vibrators

The main goal of these tools is to compact newly poured concrete by eliminating trapped air and excess moisture. This process, essential for construction, secures the concrete in the formwork, preventing product faults and ensuring proper consolidation.

Types of Vibrators Used in Construction

1. Internal Vibrators

Internal vibrators, also known as immersion or concrete needle vibrators, are the most common on construction sites. These consist of a steel tube with a vibrating element inside. The size of the poker (the vibrating element) depends on the distance between reinforcing bars in the formwork.

  • Needle sizes range from 25 mm to 90 mm.
  • For column and beam structures, use 40 mm and 60 mm needles.
  • Strong footing and bridge structures require 75 mm and 90 mm needles.
  • Vibration frequencies can go up to 15,000 rpm.

2. External Vibrator

Also known as a shutter shape vibrator, the external vibrator includes a base plate and is used to compact precast and freshly poured concrete surfaces. It’s powered by a three-phase induction motor and is trustworthy and easy to maintain.

  • Construction is closed and typically made of aluminum alloy casting.
  • Mounted horizontally or vertically on the formwork.
  • Operates at a frequency suitable for effective compaction.

3. Surface Vibrator

Permanently affixed to the concrete mass, surface vibrators are excellent for shallow elements, especially when used with low water to cement ratio concrete. They include pan vibrators and vibrating screeds.

  • Ideal for compacting small slabs and horizontal surfaces.
  • Spin at a frequency of around 4000 rpm.

    • 4. Vibrating Table

    The vibrating table is unique, maintaining the principle of vibrating both concrete and formwork. It involves a fast-spinning eccentric weight, producing circular motion, with a frequency range of 1,500 to 7,000 rpm.

    • Horizontal component of vibration can be neutralized.
    • Effective for various concrete diameters and laboratory purposes.
    • Electrically or pneumatically controlled vibrating tables offer consistent treatment.

    Conclusion

    Understanding the diverse types of concrete vibrators and their applications is crucial for achieving proper compaction in construction, ensuring the durability and strength of concrete structures.