SOAKWELL INFORMATION

Transcription

1 SOAKWELL INFORMATION This document gives detai s on the Pastube range of Soakwe products, incuding the physica characteristics. It aso describes simpe design measures for Pastube soakwes and detai on instaation. PLASTUBE SOAKWELLS

2 Introduction Pastube Soakwes are manufactured by spiray winding a strong ribbed profie strip into pipe. The strip is sotted or perforated between the ribs giving a continuous egress surface for the entire depth of the Soakwe. Soakwes are designed in order to dissipate the runoff from rainfa events into the ground rather than into the domestic stormwater system. In this way they provide an aternative exit point for stormwater and a sma storage voume for water.. Advantages Lightweight:- Being very ight and one-piece, the Rib Loc Soakwe can be easiy paced on any site. For exampe, the standard Soakwe 600 x 600 weighs ony 4.4kg. Chemica Resistance:- Pastube Soakwes, manufactured from PVC, are highy resistant to most acids and soi chemicas therefore outasting other products. Superior Egress Hoes:- The even distribution of the egress hoes aows for even outfow of water, thus reducing the possibiity of differentia movement of the surrounding soi from uneven moisture content. Reduced Soi Ingress:- The ribbed configuration combined with the sma egress hoes prevents arge soi partices from entering the Soakwe.

3 Soakwe Configuration Soakwes are currenty suppied in the standard configurations: SIZE NUMBER & DESCRIPTION NOMINAL DIAM (mm) NOMINAL DEPTH (mm). STANDARD STANDARD STANDARD SIZE NUMBER & NOMINAL NOMINAL DESCRIPTION DIAM (mm) DEPTH (mm). SPECIAL R 500. SPECIAL OR SPECIAL OR 500 Other configurations can be manufactu red by Rib Loc, depending on the nature of the job. 3 Soakwe Design In designing for Pastube Soakwes, it must be remembered that the permeabiity of the soi is generay the governing factor. The abiity of the soi to transport water is the imiting factor in Soakwe design. This is true in a cases uness the Soakwe is paced in materias such as graves or crushed rock. 3. Behaviour of Rib Loc Soakwes Pastube Soakwes are instaed so as to dissipate stormwater runoff. The process of runoff dissipation from the Soakwe is begun as soon as entering the Soakwe. For storms of onger duration the Soakwe may become more fu, depending on the magnitude of the rainfa event, the size of the Soakwe and the permeabiity of the soi. The cacuations described beow refer to the peak egress condition, when the Soakwe is fu thus giving a imiting situation. 3

4 3. How to Determine Required Soakwe Note that generay soakwe dissipation rates are imited by the surrounding soi, therefore k vaues of the soi shoud be used in cacuation. soakwe -3 k for Pastube 40 profie = 4.3 x 0 m/s h h q = q = k A h k π r h k π D 0.5 h + Note that water egressing through the soakwe base is driven by peak pressure, whist through the was the driving pressure varies ineary. For the purposes of cacuation, taking the average driving pressure for the was is a cose approximation. The foowing assumes the base is not concreted. Thus: For the base h = For the was h = / Therefore q = k π r k π D + ( π r D ) q = k π 4

5 3.3 Typica Soi Permeabiity Factors Coefficient of Permeabiity (m/s) Note that the figure above gives typica vaues. In most appications, due to great variabiity in soi permeabiity between ocations, it is generay advisabe to obtain site specific data. 4 Instaation Instructions. Cear the area of ground where the soakwe is to be instaed. Cut out hoe in soakwe for inet pipe.. Dig the soakwe in by removing the soi from inside the we. This ensures that the surrounding soi remains in its origina compacted condition, thus reducing the possibiity of subsidence around the we. Minimum depth shoud be: soakwe depth + thickness of a brick + thickness of the id + 00mm. Ground eve instaation may aso be considered for easy maintenance (dimensions as above ess 00mm). 3. Once the desired eve has been reached, ift we and pace 3 bricks under the edge of the we for support. Pace bricks equidistant around the circumference (see diagram). 4. Pace broken bricks or rubbe on the foor of the we to eiminate erosion of the bottom by the water faing from the inet pipe. 5. Insert inet pipe. 6. Fit cover and backfi. Note: Heavy Concrete covers shoud generay be paced on a pinth or simiar, to avoid pacing direct oads on the soakwe. RIB LOC SOAKWELLS 5