Kessel Aqualift F Basic Einbau- Und Bedienungsanleitung Seite 72

5.10 Backfill the excavation pit
Fill the excavation pit with suitable filling material
(crushed stone ballast with size 0/16 grain, 50 cm all
round), whilst compacting the filling material properly (e.g.
with a vibrating plate) to Dpr ≥ 95% every 30 cm.
For proper fastening, surround the base section with lean
concrete (see lean concrete wedge(1) in the figure).
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