Joint-Filling and Compaction
Once a sufficient area of pavers has been placed, fine sand for jointing is brushed into the joints. The use of dry material ensures rapid penetration of the joints. Graded materials of maximum particle sizes no greater than 1.18mm and containing no more than 10% by mass passing the 75(m size, have proved satisfactory. Suitable sands may be found among those complying with requirements of Grading F in BS 882 or Type G in BS 1200.
The use of sand that might lead to staining should be avoided.
After brushing into the joints, the surplus sand is brushed away before passing over with a vibrating plate compactor.
The pavers are vibrated into position on the sand bed to within one meter of the unrestrained edge, using two or three passes of the vibrating plate compactor. This can transmit an effective force in the range of 50-75 kN/m2 at a frequency of 60-100 Hz and has a plate contact area of between 0.2 and 0.4 m2.
After this, the whole sequence of spreading and brushing in jointing sand, removing the surplus and vibrating two or three passes of the compactor should be repeated once more. Compacting should be undertaken as soon as is reasonably practicable after placing, though it should not be performed closer than one metre from any unrestrained edge.