A400M MRO Hanger RAF Br ize Nor ton

Type o f Sys tem: S to rmwate r A t tenua t ion

Date o f i ns ta l l a t i on : Ju l y 2014

Tank s i ze : ASP Tank 4697m A400M Tank 3542m

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S i te P rob lem:

A RAF base in B r i ze Nor ton requ i red two b ig

tank to accommodate 8239m o f su r face wa te r

airplanes. A so lu t ion was needed to he lp a l l ev ia te

f l ood r i sks a round the s i te tha t wou ld a l l ow t ra f f i c

t o con t inue mov ing du r ing heavy s to rm even ts and

p reven t f l ood damage to su r round ing p rope r t i es .

P ro jec t/ C l ien tRequ i rements :

The tank was to be loca ted benea th a heavily

trafficked area by HGV vehicles and airplanes wi th

a high water table (Very close to the ground level).

A so lu t i on had to be found tha t wou ld accomoda te

these requ i remen ts . Th is mean t tha t on top o f

dea l ing w i th the usua l s to rmwate r requ i remen ts , the re

was a l so need to cons ide r s t ruc tu ra l l oad ing f rom the

su r round ing road t ra f f i c . Fur thermore the scheme was

to be adop ted by Ke lda Wate r and the roads had to be

comp l ian t w i th h ighway au thor i t y requ i rements who had

spec i f i ed requ i remen ts fo r i nspec t ion and ma in tenance

access po in ts as we l l as va r ious o the r requ i remen ts fo r

Environmental Sustainable Solutions Ltd

Sladen Mill, Halifax Road, Littleborough, Lancashire, OL15 0LB

Tel: +44 (0) 1706 374416Fax: +44 (0) 1706 376785 Email: sales@y-ess.com

Web: www.y-ess.com

Registered in England No. 03115064 Registered Of ce

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to be installed in a deep excavation with high water table, and aheavily trafficked area above by HGV vehicles and

the supp ly o f appropr i a te tes t da ta . Access to the then current

No te : - Ke lda Wate r a re respons ib le fo r the ma in tenance o f t he su r face wa te r i n f ras t ruc tu re on the s i te .

tanks (tubular) proving problematic, based on "confined space entry regulations.

ESS So lu t i on :

ESS spec i f i ed a modu la r VersaVo id , Pluvial Cube and

Aquadrain tank w i th a vo id ra t io o f 96%, th i s p rov ided 3

approx ima te ly A t 8239m (7909m Nett ) s to rage capac i t y

f o r excess s to rmwate r runo f f f rom the s i te .

The 320kN/m 2 & 400kN/m load ing s t reng th p rov ided

by each modu le gave the tank the requ i red s t ruc tu ra l

s tab i l i t y to cope w i th l oad ing f rom above . The

120kN/m 2& 200kN/m la te ra l s t reng th p rov ided

the same capab i l i t y ho r i zon ta l l y a l l ow ing the tank

to cope w i th any s ide load ing tha t may be

induced f rom t ra f f i c f l ows e i the r s ide o f the tank .

Un l i ke o the r p roposed c ra te sys tems , VersaVo id ’s,

Pluvial’s and Aquadrain modu la r cons t ruc t ion p rov ided

the requ i red f l ex ib i l i t y to accommoda te the heavy

l oads .

O the r add i t i ons inc luded a mass ive number o f

160ø

access /ven t p ipes as we l l as 600mmø inspec t ion

un i t s above the tank ( fo r ma in tenance and inspec t ion ) .

Once ins ta l led , the tank is wrapped in a water t ight , heat -we lded Tuf lex l in ing which is fur ther pro tec ted wi th in a Geotex 300PP Protec t ion F leece . A l l inspect ion chambers and out le ts a re wrapped in pre formed Tuf lex c loaks and heat we lded to the tank l in ing .

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A400M MRO HangerRAF Br ize Nor ton

access /ven t

ø access chamber600

Spec ia l Cons ide ra t ions : The 1m w ide P luv ia l Cube a r round the pe r ime te r w i th 4 l aye rs o f Aquadra in 50 / 200mm deep .ASP Tank

Con f igu ra t i on : 4697m /1 .8m & 1.075m deep tank (Steped)

A400M TankCon f igu ra t i on : 2725m x 1 .3m deep Tank

: 3542m

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To ta l : 8239m3

A400M MRO HangerRAF Br ize Nor ton

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ASP Tank

Spec ia l i s t Cons ide ra t ions : Load ing Comp l iance

Due to VersaVo id , P luv ia Cube and Aquadra in

be ing independen t l y tes ted accord ing to C IR IA

gu ide l i nes (and by two separa te ins t i t u t i ons ) , ESS

were ab le to p rov ide a l l o f t he spec if i ed tes t da ta .

The in fo rmat ion p rov ided comp l ied to a l l t he

necessary documen ta t ion suc has C IR IA C680 ,

609 and 697 . A l l t es ts ( i nc lud ing compress ive

s t reng th , l a te ra l s t reng th and long te rm c reep

tes ts ) comp l ied to C IR IA gu ide l i nes as ou t l i ned

in C IR IA C697 and fo l l ow ing de f ined methodo logy

ou t l i ned in C680 . On top o f th i s , ESS supp l ied i t sown in -house tes t da ta .

Preformed Tuf lex c loaks are heat we lded to inspect ion chamber openings .

A400M MRO HangerRAF Br ize Nor ton

A400M Tank

Summary :

VersaVo id and P luv ia l Cube p rov ided a des ign

tha t me t a l l o f t he s t r i ngen t requ i remen ts se t by

the loca l au tho r i t y and the H ighways Agency

inc lud ing C IR IA requ i remen ts fo r bo th load ing and access .

Modu la r con f igu ra t ion a l l owed fo r a f l ex ib le ,

i dea l s i t e so lu t i on tha t worked w i th o the r

ex i s t i ng i n f ras t ruc tu re bo th above and be low

g round leve l . The modu la r assemb ly fu r the r

reduced ins ta l l a t i on t imes a l l ow ing a much more

economica l so lu t i on to be found .

Load bear ing capab i l i t i es and h igh vo id ra t i os

p rov ided the mos t e f f i c i en t so lu t i on fo r a

res t r i c ted s i te w i th l oad ing i ssues .

A400M MRO HangerRAF Br ize Nor ton

The c l i en t had spec i f i ed fo r access as a ma in

p r io r i t y o f t he ins ta l l a t i on . VersaVo id ’s & Pluvial cube’s

un ique , open and access ib le s t ruc tu re was

immed ia te l y ab le to p rov ide to ta l access w i th the

add i t i on o f an ex te rna l access po in ts . Fo r

ve r t i ca l and ho r i zon ta l access ESS sugges ted inspec t ion un i t s

to be ins ta l l ed above the tank and on the s ides ,

a l l ow ing sa fe access tha t d id no t i n te r fe re w i th

the heavy t ra f f i c f l ows .

For ho r i zon ta l access p ipes were ins ta l l ed on a l l

t h e s i d e s o f t he tanks and 600 d ia access chambers

were ins ta l l ed above each in le t /ou t le t p ipes .

Th is p rov ided comp le te access th roughou t the tank fo r

any fu tu re ma in tenance / inspec t ion to be ca r r ied ou t .

Spec ia l i s t Cons ide ra t ions : Access