Excavation Pits And Bedding - Rehau Rausikko Box Notice De Mise En Œuvre

04 Excavation pits and bedding

EN
The applicable legislation on accident prevention for excavation and also
the applicable standards for digging excavation pits and trenches are to be
observed.
The length of the trench equates to the length of the tank plus working area.
The width of the trench equates to the width of the tank plus working area.
The trench depth of a Box infiltration or attenuation tank equates to the
height of the tank plus the coverage height and the height of the fine gravel
bed (see below).
The trench depth of a trough-Box-infiltration-system (with a Box-infiltration-
tank underneath the trough) equates to the depth of the trough plus the
depth of the tank (according to design) and also the thickness of the top soil
layer (normally 0.3m) and the bedding (see below).
The base of the trench must be free of stones, even, and without any
gradients. The load bearing capacity and permeability of the base must be
at least equal to the grown ground. For systems without traffic load, we
recommend an E ₂ value of at least 30 MN/m² and for systems with traffic
v
load, a value of at least 45 MN/m². If necessary, suitable measures are to be
taken (soil replacement, re-compacting, etc.).
An approx. 10cm thick layer of fine gravel or grit (e.g. corn size 2/5 or 2/8) is
to be laid on the base. The bed is to be laid thinly and evenly using suitable
equipment (planer or similar). Laying the bedding layer is to be carried out
with great care.
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