VIBRATOR SHAFT ONLY 60MM

Contractors and site managers must comply with vibration 
control procedures to avoid damage to nearby structures
 during a construction project. Site managers will ensure 
vibration monitoring tools are both implemented and
 functional, and pre/ post construction crack
 inspections may be performed.
The abrasion resistance of concrete surfaces
 is normally improved by adequate compaction.
 However, excessive vibration, or excessive working
 of the surface, can cause an excessive amount
 of mortar (and moisture) to collect at the surface, 
thereby reducing its potential abrasion resistance.
Vibration of fresh concrete reduces its internal shear strength, 
and enables concrete to momentarily 
liquefy to facilitate the consolidation process.
 When the vibration stops, the liquid flow subsides.