Kessel 93007/120D, Installation And Operating Instructions Manual

Page: 31 / 116

4.8 Backfill the excavation pit
CAUTION
Note the structural calculations for traffic safety. Chamber installation for load class D makes a load distribution plate
made of reinforced concrete necessary (exception: not necessary for standard road construction).
Determine the required load class and structural calculations in accordance with the environment / use condi-
tions.
Request an appropriate reinforcement drawing from the KESSEL hotline.
(1) Subsoil (crushed stone) (5) Ground
(2) Tank bed (sand) (6) Base course
(3) Separator according to the structural calculations (7) Top of tank
(4) Back fill material (crushed stone) (8) Load distribution plate (for load class D)
Fill the excavations with crushed stone (0-16 mm diameter), at least 50 cm all around; place in layers of maximum 30 cm
and compact each layer of fill material properly to 97% Dpr (e.g. using vibrating plate).
At the same time, the tank must be filled with water so that a maximum difference of 30 cm exists between the liquid level
and the level of the fill material.
The required excavation pit slope angle β must be observed all the way round.
The assignment of internal frictional angle φ of the fill material, and permissible excavation pit slope angle β must be car-
ried out in accordance with EN 4124.
EN
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