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Installation conditions
3.
3.1
Choice of location
Distance from basement > 6 m
Distance from ground water minimum > 1 m
The distance from the existing or planned trees must be at least the expected spread of the trees
crown.
3.2
Excavation dimensions
The measurements of the excavation is in accordance with the number of drainage blocks to be installed
by multiplying the length and width dimensions.
The following table gives the required earth covering and the maximum installation depth to the lower
edge of the blind drain:
*The maximum installation depth* or earth covering* is related to the ground substance with an inside
angle of friction from
ϕ
=
40,0°.
°The material or raw material specification possibly contains recycled material.
Transportation loads
Infiltration Tunnel
Infiltration Tunnel Twin
Short-term
max. 100 kN/m²
max. 75 kN/m²
Long-term
max. 59 kN/m²
max. 35 kN/m²
Without traffic loads
min. Earth covering
250 mm
250 mm
max. Earth covering*
3740 mm
1480 mm
max. Installation depth*
4250 mm
2500 mm
Vehicle loading
min. Earth covering
250 mm
500 mm
max. Earth covering*
3490 mm
1480 mm
max. Installation depth*
4000 mm
2500 mm
lorry 12
min. Earth covering
max. Earth covering*
max. Installation depth*
500 mm
3240 mm
3750 mm
-
HGV 30
min. Earth covering
max. Earth covering*
max. Installation depth*
500 mm
2740 mm
3250 mm
-
HGV 40
min. Earth covering
max. Earth covering*
max. Installation depth*
500 mm
2490 mm
3000 mm
-
HGV 60
min. Earth covering
max. Earth covering*
max. Installation depth*
750 mm
1740 mm
2250 mm
-
Incl. endplates 1220 mm