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6.
Installation and assembly
6.2.6 Insertion and filling
The shafts should be carefully lowered into the
excavation avoiding any sudden jolts.
>300
The shaft must be filled 1/3 full of water before
commencing the back filling. The back fill should
be carried out using 8 to 16mm single sized gravel
2. 3/3
and compacted in 30cm (max.) layers until the top
1. 1/3
of the shaft is reached.
The individual layers and the lower zone of the
shafts must be well compacted (with a hand tam-
per). Be careful to avoid damaging the shafts when
compacting the gravel. Mechanical compression
machines must never be used. The trench sur-
round must be at least 300 mm wide.
Please note: It is especially important for the filling in the bottom third of the shaft to be well compacted
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