What is a Poker Vibrator?
A poker vibrator consist of an electric weight encased in a housing and may be driven by an electric or pneumatic motor or a petrol or diesel engine. Poker diameters range from 25 to 75 mm.
How To Use Poker Vibrator?
A poker vibrator should be used as follows
- Insert the vibrator quickly. When compaction is complete, withdraw it slowly to avoid leaving a hole.
- Compaction is complete when the surface of the concrete gets a water sheen and air bubbles no longer break through it.
- Concrete must be placed in layers and the tip of the poker must penetrate the layer below to knit the concrete.
- The poker must be inserted at regular intervals in both directions. Points of insertion should be no more than 10 times poker diameter.
- Where void formers occur, concrete should be placed and compacted from one side until it has flowed under the obstruction.
- The poker must not touch the formwork.
- Slump of concrete for compacting by means of a poker vibrator is normally between 50 to 125 mm.