10.1.3 Earth pit with plastic-sheet gasholder
Fig. 10.7: Constructional drawing of an earth-pit
biogas plant with plastic-sheet gasholder. Vd = 11
m³, Vg = 2.2 m³. Material requirements: Excavation
16 m, Rendered area 28 m², Sheeted area 10 m²
(Source: OEKOTOP)
10.1.4 Estimating the earth-pressure and hydraulic forces
Fig. 10.8: Schematic diagram of earth-pressure and
water-pressure forces
In-depth forces, h (e, w)
pW = wW • hw
pW = hydrostatic pressure at depth hw (m) wW = specific weight of water
= 1000 kp/m³ pW = 1000 • h (kp/m²)
pE = wE • ce • he
pE = active earth pressure, i.e. force of pressure of dry, previously loose but now compact column
of earth on a solid vertical wall
wE = specific weight of dry backfill earth
= 1800 . . . 2 100 kp/m³
he = height of earth column (m)
ce = coefficient of earth pressure for the earth column in question
= 0.3 . . . 0.4 (-)
pE = (600 . . . 700) • h (kp/m² )
Force acting on a surface
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