aquaflow permeable paving drainage systems - greenspec formpave top hat seal ... heavy rain to...

®Formpave

Hanson Formpave

Aquaflow®

permeable pavingSustainable urbandrainage systems

Available in Formpave EcoGranite

FM 12515

edition 6

1

Sustainable urban drainage systemAquaflow

®

permeable paving

Hanson Formpave

Formpave Used on hundreds of contracts worldwideTested over15 years Water harvestingClean and controlled water dischargeBioremediation of hydrocarbons Retentionof heavy metals Design service availableBBA certification Formpave EcoGraniteAn Aquaflow surface has the capacity todeal with rainfall intensities approximately90 times greater than that required by theregulations.* Formpave also manufacturea comprehensive range of pavers, kerbsand fittings.The Aquaslab, Aquasett andAquaflow block is available in Formpave EcoGranite, anenvironmental alternative to theuse of freshly quarried granite.Formpave's unique granite mixincludes both Stent and Slag; by-products of Cornish ChinaClay and the South Wales steel industry.

* New Building Regulationsbecame effective on 1 April 2002

Introduction

System overview

The Aquaflow range of paving blocks

System detail - principal benefits:

Lower construction costs

Control of run-off

Aquaflow hydraulic performance

Discharge Water

Quality of discharge water

Water harvesting and re-use

Geothermal heating and cooling

Roof water

Maintenance and performance

Heavy duty use

Design criteria

Design service

Construction Drawings:

Aquaflow paving in conjunction with standard block paved road surfaces

Aquaflow paving in conjunction with asphalt road surfaces

Construction running surface - adoptable design

Down pipe drainage into tanked system

Aquaflow paving in conjunction with waterharvesting drainage system

Sloping sites tanked system

Formpave top hat seal

Aquaflow paving in conjunction with Geothermal heat transfer

Soft landscaping and Aquaflow paving

Specifications:

Q24 Sustainable urban drainage system

Inbitex

Distribution Tanks

Construction

Method of accessing services and reinstatement

Colours and finishes

Pack sizes and weights

Formpave kerb options

Maintenance

Patents

1-3

4-7

8-9

10-15

11

11

11

11

11

11

12

12

12

14

14

14

16-19

16

16

16

17

17

18

18

19

19

20-22

20

21

21

21-22

22

23

24

24

24

inside back cover

Hanson FormpaveSituated at Coleford in the Royal Forest of Dean, the HansonFormpave works is one of themost sophisticated of its type inEurope. The technology used inthe works and the Company'squality assurance scheme providescomplete works traceability ofevery block made. The works hasBS EN ISO 9001: 2000 QualityAssurance accreditation andHanson Formpave is a BSIregistered company.

If you would like information on Hanson Formpave's otherproducts please visit our web site www.formpave.co.uk or call our Sales office on 01594 836999.

FM 12515

32

The Problem Increasing urbanisation and rapid run-off have put a tremendous strain on conventional storm waterdrainage systems. This has resulted in sewers and culvertsbecoming overloaded during periods of heavy rain andcontamination of streams and rivers.

Heavy metals, hydrocarbons, rubber dust, silts and otherdetritus are all deposited on impermeable surfaces duringdry weather. These are scoured off such surfaces duringperiods of heavy rain and transported at best into expensivetreatment works, or directly into rivers and streams wherethey cause severe environmental damage.

SUDS should be used on all sites to minimise the impact of the development on the environment. In Scotland the useof the SUDS approach is a legal requirement.

The Solution - Source Control Sustainable Urban DrainageSystems (SUDS) are increasingly being used to prevent run-off and flooding, and as a method of collecting andcleaning storm water.

The Formpave sustainable urban drainage system allowsheavy rain to infiltrate through a permeable concrete blockpaved surface into a unique sub-base before being releasedin a controlled manner into sewers or water courses.

Discharge rates in accordance with greenfield run-off can be readily achieved if required. Alternatively, if the underlyingsub-grade is suitable the water can be infiltrated directly intothe sub-grade.The water leaving the Formpave Aquaflow system is cleanedby filtration and microbial action and can be used forsecondary non-potable uses such as flushing toilets andwatering soft landscaping.

A further advantage of the system is that roof water can be drained directly into the sub-base via a rodable sump, or if siphonically drained, through a dispersion chamber.

Formpave's sustainable urbandrainage systems and Aquaflowpermeable paving products aresuitable for use on: Car parks,Industrial estates, Retail centres,Pedestrian areas, Domesticdrives, Motorway services, Airport service areas and aprons,Garages, Lorry parks and otherheavy duty applications.

New Building Regulationsbecame effective on 1 April 2002and for the first time address thetopic of drainage from hardsurfaces by means of a permeablesurface. In paragraph 2.4 theregulations state that a rainfallintensity of 0.014 litres per secper m2 can be assumed fordesign purposes.

Aquaflow, the permeable pavingproducts designed to be usedwith the Formpave sustainableurban drainage system, letthrough 2.5 litres/sec/m2.

An Aquaflow surface has thecapacity to deal with rainfallintensities approximately 90 timesgreater than that required by theregulations.

Sustainable urban drainage systemAquaflow

®

permeable paving

All information contained in this brochure is based ontypical schemes. Therefore it is recommended that eachsite should be designed tosuit its individual specificconditions and restrictions.

54

Sub-base in two layers*100mm depth top layer of 5-20mm

250mm depth bottom layer of 10-63mm

SC intergrid*

Optional SC intergrid*

Inbitex*

SC membrane / Inbitex on

infiltration system*

2-6mm

Clean stone

Concretehaunching

Aquaflow block

standard blockHanson Formpave

Standard kerb

block

Aquaflow block

standard blockstretcher courseAquaflow block

standard block

Inbitex

SC membrane*brought up to

haunched Kerband cut off flush

with surface ofAquaflow blocks

or slabs

Hydraway fin drain connected to 110mmPVC-U pipe with Formpave top hat seal*

Inbitex*



Inbitex*



Hydraway fin drain connected to 110mmPVC-U pipe with Formpave top hat seal*

2-6mm

Clean stone

* Sub-base in two layers

100mm depth top layer of 5-20mm250mm depth bottom layer of 10-63mm

Inbitex*

Concretehaunching

Aquaflow MLE

end block

Aquaflow MLTB

top and bottom blockHanson FormpaveStandard kerb

block

Aquaflow block

standard blockstretcher course Aquaflow ML



SC intergrid*

Optional SC intergrid*

Inbitex

SC membrane*brought up tohaunched Kerband cut off flushwith surface ofAquaflow blocksor slabs

W O R L D L E A D E R S I N S U S T A I N A B L E U R B A N D R A I N A G E S Y S T E M S

There are 3 system designs

Each design can be tailored forinfiltration or tanked and to fulfilthe requirements of the project:

Infiltration Used to infiltrate the water directly into a suitable sub-grade.

Tanked Used to attenuate water before release, harvesting for re-use orwhere difficult or contaminated sub-grades are encountered.

Sustainable urban drainage system For a sub-grade CBRof between 2-5%Parking areas subject totrafficking by cars andvans only.

For a sub-grade CBRof 5% or greaterParking areas subjectto trafficking by carsand vans only.

For a typical footpathconstructionFor Aquaflow, Aquasettand Aquaslab paving.

The diagrams illustrate the

three designs applied to a typical

Infiltration system which uses

two pervious inbitex geotextiles.

On Tanked systems the underlaying

pervious geotextile is replaced

with an impervious SC membrane.

See page 6 for detailed information

1 2 3

* see specifications on pages 20-22

The isometric drawings show a tailored Tanked system. The Tanked system is available in the three designs described above.

76

Each of the 3 basicsystem designs can betailored for infiltration or tanked to fulfil thespecific requirements of the site.

Inbitex®

- thermally bonded

nonwoven geotextile

Inbitex®

has been specifically developedto optimise the cleansing of waterentering the system. The variouscharacteristics have been combinedto create a unique geotextile that aidsthe development of the naturallyoccurring microbes, and offers themrefuge during periods of drought.

For further information see page 21.

Grading of lower

sub-base stone

BS Sieve size % passing 100mm 10063mm 90-10037.5mm 60-8020mm 15-3010mm 0-5

Infiltration

The system is underlaid with apervious geotextile (Inbitex) and is suitable for use where it isproposed to infiltrate the waterdirectly into a suitable sub-grade.

Tanked

The system is underlaid by an impervious membrane (SC membrane) and is suitablefor use where it is proposed toattenuate storm water beforereleasing it in a controlledmanner, harvest the water for re-use or where difficult orcontaminated sub-grades areencountered.

The type of membrane used andthe method of sealing will dependupon the application. In somecircumstances the membrane willrequire additional protection frompuncturing and specialist adviceshould be obtained.

The impervious membranerestricts water entering the sub-grade, and preserves sub-gradestructural integrity. This is veryimportant where clay sub-gradesare encountered.

Where a completely watertightsystem is required a weldedmembrane should be used atformation level.

Laying course material

and sub-base

Both the Tanked and Infiltrationsystems utilise the same layingcourse and sub-base materials.

Depth of sub-base can be variedto suit requirements of the engineer.

The sub-base stone must becrushed, possess well definededges and be in accordance withthe Los Angeles coefficientcarried out to the requirements ofEN 1097-2 1998 clause 5.

80/60

mm

250

100

Aquaflow blocks/setts

Inbitex *

Inbitex/��

50

SC intergrid *

2-6mm clean stone *

Subgrade

Upper sub-base5-20mm stone *

Lower sub-base10-63mm stone *

80/60

mm

250

100

Aquaflow blocks/setts

Inbitex *

Inbitex/��

50 2-6mm clean stone *

Subgrade

Upper sub-base5-20mm stone *

Lower sub-base10-63mm stone *

80/60

mm

150

Aquaflowblocks/slabs/setts

Inbitex *

Inbitex/��

50 2-6mm clean stone *

Subgrade

Sub-base 5-20mm stone *

Typical system with a sub-grade CBR of between 2-5%

Parking areas subject to trafficking by cars and vans only

Typical system with a sub-grade CBR of 5% or greater

Parking areas subject to trafficking by cars and vans only

Typical footpath construction

For Aquaflow/Aquasett /Aquaslab paving

* See specification on pages 20-22

Sustainable urbandrainage system continued

1

3

The diagrams illustrate the

three designs applied to a typical

Infiltration system which uses

two pervious inbitex geotextiles.

On Tanked systems the underlaying

pervious geotextile is replaced

with an impervious SC membrane.

2

Hanson Formpave design team:01594 836999 [email protected]

photograph copyright of Sustrans

98

Aquasett combined (0.8 square metres-one pallet layer)

100 150

60/80

250

60/80

150150

150

60/80

3 3

45012052.5 105 120 52.5

300

12090

60

90300

3 3

20

40

150

60/40

20

150

33

80/60

4055 55250

1.5

20

1.51.25.5

320

35°

1.5

20

The Aquaflow ML block systemconsists of an interlocking blockwith specialist top, bottom andedge blocks and has beenspecifically designed for heavyduty applications.

The ML blocks can be laid byhand or by machine. Where theblocks are machine laid modulesof .65m2 are laid in one pass.Laying rates of over 600m2 per dayhave been readily achieved with a three man crew.

Other colours and finishes

such as EcoGranite are available

to special order.

Aquaslab®

For use on Pedestrian areas

Size

300 x 450 x 60mm

Laying pattern

Staggered stretcher bond

Colours*

Natural, Burnt Red, Red brindle,Golden brindle and Charcoal

Finish

StandardBush hammered to special order

Aquasett®

For use on footpaths, domestic drives and roads (80mm)

Range of colours and the Olden finishmake the Aquasett appropriate for use inconservation areas or on projects wherearchitectural heritage is a major consideration.

Sizes

150 x 250 x 60/80mm

Laying pattern

Staggered stretcher bond or 90o herringbonefor trafficked areas.

Colours*

Traditional, Red Brindle, Vendage andPennant.

Finish

Olden Bush hammered to special order

Aquasett combined ®

For use on footpaths and domestic drives

Range of colours and the Olden finish makethe Aquasett combined appropriate for use inconservation areas or on projects wherearchitectural heritage is a major consideration

Sizes

Large 150 x 250 x 60/80mm Medium 150 x 150 x 60/80mmSmall 100 x 150 x 60/80mm

Ratio of blocks in 0.8 square metremanufactured format: 10 large, 14 medium and 7 small.

Laying pattern

Staggered stretcher bond

Colours* Traditional, Red Brindle, Vendage and Pennant.

Finish

Olden Bush hammered to special order

Aquaflow block®

For use on car parks, drives and moderatelytrafficked areas

Sizes

100 x 200 x 60/80mm

Laying pattern

Must be laid in 90o herringbone

Colours*Natural, Burnt Red, Red brindle,Golden brindle and Charcoal.

Finish

StandardBush hammered to special order

Aquaflow ML block®

For Roads and heavy duty use

Size

80mm

Laying pattern

Include stretcher course around edge inconjunction with MLE and MLTB


Finish

Standard

Not available in EcoGranite

Formpave have designed a rangeof Aquaflow paving blocks to beused in conjunction with eithertanked or infiltration systems.

The range consists of six blocksmanufactured from concrete witha tensile splitting strength inaccordance with BS EN 1338:2003.

Included within the range is theAquaslab which has been designedfor use on non-traffickedpedestrian areas.

All of the blocks and slabs providedrainage through vertical channelsand will allow water through thesurface at a rate of approximately9000mm per hour (9000 litresper m2 per hour). The Inbitexgeotextile beneath the layingcourse will allow approximately4500 litres per m2 per hourthrough and this figure should beused for design purposes.

44200

60/80

100

40/60

20

4030 30100

23.5173.2

150

100

50 196.7150

80

83.960.4

23.5

200200

80

83.9

4

196.7

23.5

173.2

200

80

20

60

1.51.25.5

320

35°

1.5

20

1.5

20

Aquaflow MLE® top drawing

End blockFor use with Aquaflow ML blocks

Aquaflow MLTB® bottom drawing

Top and bottom blockFor use with Aquaflow ML blocks

Size

80mm


Finish

Standard

Not available in EcoGranite

The Aquaflow®

range of permeable paving *

1110

System details - principal benefits Cumulative applied and effluent oil

0 200 400 600 800 1000 1200

massof oil (g)

-100

100

300

500

700

900

1000

Percentage of Heavy Metals Removed

%removed

75

80

85

90

95

100

Nickel Copper Cadmium Lead Palladium Platinum

Oil Added

In effluent

Number of days

Data provided by the kindpermission of:

Cumulative applied and effluent oilStephen Coupe, University ofCoventry.

Percentage of Heavy Metals RemovedDr Chris Jefferies and Fiona Napier,Urban Water Technology Centre,University of Abertay, Dundee.

Lower construction costs Control of run-off Aquaflow hydraulic performanceQuality of discharge water Waterharvesting and re-use Geothermalheating and cooling Roof waterMaintenance and performance Heavyduty use Design criteria Design service

continued overleaf

Lower construction costs

From experience it has beenshown that total construction costsare lower than conventionallydrained surfaces.

When using the Formpave Aquaflowsystem it is not necessary toincorporate the gullies, drainagepipes, drain runs, oil and silt trapsand flow control mechanisms thatare needed for traditional drainage.

When comparing relative costs it isimportant that all costs associatedwith traditional drainage areincorporated. e.g. gullies, channels,hydraulic controls, detention ponds,petrol interceptors, culverts etc.

It should be noted that theFormpave sub-base is opentextured and therefore has a greaterrate of spread than HighwaysAgency Type 1 sub-base.

Formpave specified sub-basestone weighs approximately 1.8 tonnes per m3.

Type 1 sub-base stone weighsapproximately 2.2 tonnes per m3

(based on carboniferous limestone).

Control of run-off

Run off during periods of heavyrain is eliminated. Aquaflowproducts allow water to infiltratethrough the surface of the systemat a rate of approximately9000mm per m2 per hour.

Aquaflow hydraulic

performance

For rainfall events with smallrainfall depths (5mm and below)there is no effective runoff from apermeable pavement.

The results show that for shortduration events there is significantattenuation of the peak discharge.

The peak discharge from thepavement is less than the flow ratefalling onto the pavement and forlong duration rainfall events,equilibrium conditions are achieved- the outflow matches the inflow rate.

One can expect a variability in theresponse to a given rainfall eventdepending upon antecedent rainfall.The overall performance is notsignificantly affected by theantecedent conditions if the eventis significant.

The results of the study show thatpermeable pavements emptyrapidly and easily satisfy therequirements on the time to halfempty to avoid potential floodingfrom multiple storms.

For short duration events, of theorder of 30 minutes or less, thepeak discharge appears to berelatively insensitive to the lengthof the pavement, up to realisticlengths. This emphasises theeffectiveness of permeablepavements in attenuating peakdischarges for short duration events.

The model analysis indicated thatunder most conditions within thepermeable pavement the depth offlow is small and flow velocitiesare low.

Thus proving reduction in surfacewater run-off to sewers and water-courses during peak storm events.

Extract from an independentstudy undertaken by H R Wallingford Limited

Discharge water

The compacted sub-base has avoids ratio of approximately 30%which allows storm water to beattenuated within the system andreleased in a controlled mannerover a period of time.

Discharge rates in accordancewith greenfield run-off can bereadily achieved if required. Where the underlying sub-grade is suitable, water can be infiltrateddirectly into the ground. Infiltrationcan be considered even where thesub-grade would not be suitableunder BRE Digest 365 criteria.The reservoir capacity of the sub-base allows water to be storedbefore slowly infiltrating over aperiod of time.

Approximately 30% of waterentering the system is lost throughevaporation and does not leave inthe form of exit water.

Quality of discharge water

Analysis of exit water from thesystem has shown it to be asclean as the water dischargedfrom a modern sewage works.

The layers of stone and geotextileact as a type of trickle filter.Organic matter, silt and loam iscaught by the geotextile and heldwithin the laying course. Heavymetals have an affinity toparticulates; adhering to thesurface of the organic matter andsilt. They are therefore stabilisedand retained within the sub-base.

Hydrocarbons are digested by apopulation of naturally occurringmicrobes. Research undertaken atCoventry University on microbialgrowth has shown that the systemis capable of degrading at least400g of oil per m2 per annum.

The Environment Agencies haveconfirmed that silt traps and oilinterceptors are not required asthe system catches silts anddegrades oils.

An additional advantage is that water exiting the system has a pHof approximately 7.5. (UK rainfallhas a ph of approximately 4.5)

Deformation due to trafficking

HAUC specification for reinstatement of openings in highways

1000-1000 -800 -600 -400 -200 0 200 400 600 800

mm

0.0

-5.0

-10.0

-15.0

-20.0

-25.0

-30.0mm

50,000 sa

30,000 sa

20,000 sa

10,000 sa

60,000 sawith wettedsub-base

Lateral position testing undertaken by The Transport Research Laboratory

1312


System details -principal benefitscontinued

continued overleaf

Water harvesting and re-use

A number of sites are harvestingand re-using water directly fromthe system.

Youth hostels and schools areusing the water for non-potablepurposes such as flushinglavatories and a large gardencentre is using this resource towater plants and soft landscapes.It has been found that water fromthe Formpave Aquaflow system iskinder to plants than tap water.

The Hanson-Formpave waterrecycling system collects rainfall inthe base of a tanked permeablepavement. Water falling onto thepavement surface and that comingfrom adjacent roofs is collectedand this water is cleaned by theInbitex geotextile layer beforestorage. The recommended usesfor this water are toilet flushing,garden watering and car washing.Together, these uses can reduceby 50% or more the householdrequirement for mains water.

A driveway of 40m2 when full of rainwater can provide enoughwater for around 1 months useeven with no extra rainfall.

Geothermal heating and

cooling

Hanson-Formpave presents apavement-based system capableof reducing a building's reliance ongas or electricity for heating andcooling by up to 80%. A patentedsystem for heat capture fromstored water can be used togenerate 6 kilowatts of energy forindoor climate control. A heatpump moves the heated or cooledwater through either underfloorheating or radiators. The payback

period on the system is typicallybetween 3 and 6 years afterwhich, other than the cost ofrunning the heat pump, heatingand and cooling costs arecompletely removed.

Roof water

Roof water can be discharged into the sub-base. See page 17 fordesign details.

With gravity fed drainage it isrecommended that the water isintroduced into the sub-base bymeans of a sump with a manholecover adjacent to the paved area.Any debris can be easily caughtand cleared. The water is thendispersed within the system via adistribution tank.

Where siphonic drainage isproposed it is recommended thatyou contact the Hanson Formpavedesign team 01594 836999.

Maintenance and performance

The surface has a design lifeequivalent to standard block paving.The surface blocks require simpleroutine maintenance - see page24: maintenance specification.

Professor John Argue of theUrban Water Resources Centre atthe University of South Australiahas undertaken extensive researchon the siltation of blocks and

laying course. His researchassumed rainfall of 580mm perannum with a loading of 200 partsper million of silts. This is similar tothe annual rainfall in Newark,Nottinghamshire, and the siltloading is what would be found inan established urban catchment.

He concluded that after 35 years,surface permeability is approximately20% of the 'as new' value.

Assuming a 'worse case scenario'where after say twenty five years,90% of the surface permeabilityhas been lost through silting. The permeability of the surface isstill 9000mm x 10% or 900mm ofwater per hour per m2 (900 litresper m2). This would indicate thatthe surface permeability is stilleighteen times what is required todeal with 50mm of rain in an hour.

paving systems at a number ofacademic and independentinstitutions including CoventryUniversity, Edinburgh University,Abertay University, Delft University,HR Wallingford, University ofCantabria and TRL at Crowthorne.

Formpave have always shared(and continue to share) the resultsof this research with theconstruction industry, and it is thisapproach that has established theCompany as the world leader inpermeable paving solutions.

All drawings provided by HansonFormpave are protected byCopyright and Design rights andshould not be duplicated withoutpermission from the HansonFormpave design team.

The following information can beprovided by contacting the HansonFormpave design team: Standarddetail in 'AutoCAD' format alsospecifications for laying,reinstatement and maintenance as shown on pages 20-24.

14 15


System details -principal benefitscontinued

Heavy duty use

Trials undertaken at the TransportResearch Laboratory validated thesub-base design for heavy dutyuse. It is recommended that thissub-base design is used whereverthere is a possibility of over-run byheavy vehicles.

The heavy duty sub-base designcomprises two separately gradedlayers of stone with an SCintergrid at the interface betweenthe two layers (a further optionalsecond SC intergrid may beinstalled lower down the sub-baseat the engineers discretion).

The standard details show a baselayer of 250mm of 10-63 stoneoverlaid by a SC intergrid and a100mm depth layer of 5-20 stone.The depth of the sub-base may bevaried at the engineers discretion.

In certain circumstances it may be necessary to include a DenseBitumen Macadam (DBM) layerbeneath the laying course, thisshould be punctured at 800mmcentres.

Design criteria

The sub-base has a reservoircapacity of approximately 30%. As a quick rule of thumb - 10m2 ofFormpave Aquaflow system with adepth of 350mm of sub-base willaccommodate 1 cubic metre of water.

Where it is proposed to drainimpermeable surfaces onto areasof Aquaflow it is recommendedthat a maximum ratio of 2:1impermeable: Aquaflow is used.

Excessive run-off from animpermeable surface onto anAquaflow area could result insiltation occurring and increasethe requirement for regularmaintenance.

Design service

Formpave offer a comprehensivefree design service to suitindividual site requirements.

The service offered by Formpave'steam of engineers includestechnical and professional advice,preparation of draft proposals, andvalidation of client's own designs.

All designs that have beenprovided or approved by HansonFormpave are covered byFormpave's professional indemnityinsurance and benefit from thecompany's 15 years experience indesigning permeable pavingsystems.

Every aspect of Formpave'spermeable paving system hasbeen independently tested andverified - both in terms of pollutioncontrol properties and hydraulicand structural performance. Duringthe past 15 years the Companyhas sponsored an ongoingprogramme of research anddevelopment into permeable

Inbitex *

SC membrane *

Road surface standardblock paving over 50mm depthof sharp sand bedding course

2-6mmcleanstone

Aquaflowblocks

or slabs

Standardkerb block

Concretehaunchingface on allhaunching

must be shovelsmooth

* Inbitex and SC membrane brought up to haunched Kerband cut off flush with surface of Aquaflow blocks/slabs

mm

80/6050

100

250

SC intergrid *

OptionalSC intergrid *

Forestedging

Uppersub-base5-20mmstone *

Lowersub-base

10-63mmstone

* Hydraway fin drain connected to110mm PVC-U pipe with Formpave top hat seal

**

mm

80/6050

100

250

Ashphalt construction

Highway Agency type 1 sub-base

2-6mmcleanstone

Aquaflowblocks

or slabs

* Inbitex and SC membrane brought up to haunched Kerband cut off flush with surface of Aquaflow blocks/slabs

Standardkerb block


must be shovelsmooth

SC intergrid *


Forestedging


Lowersub-base

10-63mmstone

* Hydraway fin drain connected to110mm PVC-U pipe with Formpave top hat seal

Inbitex *

SC membrane ***

Standardkerb block

mm

80/605080

270

SC membrane *

Inbitex *

2-6mmcleanstone *

Aquaflowblocksor slabs

Inbitex and SC membrane * brought up to haunched Kerband cut off flush with surface of Aquaflow blocks/slabs

800mm centres 800mm centres

D E N S E

Lowersub-base10-63mmstone *


Hydraway fin drain connected to 110mmPVC-U pipe with Formpave top hat seal *

M A C A D A MB I T U M E N

Uppersub-base5-20mm

stone

Inbitex *

SC membrane


mm

80/6050

100

250

Incoming pipeworkfrom roofwaterdrainage

Distributiontank with geotextilesurround on 10mm

pipe bedding

Hydraway fin drainoverflow connected to110mm PVC-U pipe withFormpave top hat seal *

300 or 500mm diametersilt trap with 350mmminimum sump

Membrane sealedwith Formpave tophat seal where pipepasses through

Aquaflowblocks/slabs

2-6mmcleanstone *

Standardkerbblock

SC intergrid *


Concretehaunching

face on all haunchingmust be shovel smooth

mm

80/6050

100

250

Uppersub-base5-20mm

stone

Inbitex *

SC membrane


Incomingpipeworkfromroofwaterdrainage

Distributiontank with geotextilesurround on 10mm

pipe bedding


300 or 500mm diametersilt trap with 350mmminimum sump

Membrane sealedwith Formpave tophat seal where pipepasses through


2-6mmcleanstone *

Standardkerbblock

SC intergrid *


Concretehaunching


Schematic pump chamber †

*

*

1716

Aquaflow paving in conjunction with standard block paved road surfacesTanked system section Aquaflow pavement with undersealing membrane

Aquaflow paving in conjunction with asphalt road surfaces Tanked system section Aquaflow pavement with undersealing membrane

Lay SC membrane, optional intergrid,270mm of sub-base and SC intergrid

Lay 80mm of dense base course DenseBitumen Macadam (DBM) over sub-base(see specification)

••

•

•

After building work is completedClean Dense Bitumen Macadam (DBM) surface

Cut 20/50mm diameter holes at 800mm centresthrough DBM surface into sub-base

••

Fill holes with 2-6mm clean stone

Lay Inbitex, 50mm laying course andAquaflow blocks or slabs

Illustrations on this page feature the Tanked system for Infiltrationreplace SC membrane with Inbitex.For further information contact theHanson Formpave design team.

Construction running surface - adoptable designTanked system section Aquaflow pavement with undersealing membrane

Construction Drawings

See specifications *See specifications *


Down pipe drainage into tanked systemAquaflow pavement with undersealing membrane

Aquaflow paving in conjunction with water harvesting drainage systemShown with the Standard Tanked system

mm

80/6050

100

250

*

*

*

Inbitex and SC membrane *brought up to haunched kerb andcut off flush with surface ofAquaflow blocks/slabs

Hydraway fin drainconnected to 110mm

PVC-U pipe withFormpave top hat seal

10 metre centres 200mm high concrete baffles110mm PVC-U unperforated pipe

Face of concrete haunching must beshovel smooth

It is recommended that on incline sites greaterthan 1 in 20 lateral restraints are incorporated

Inbitex *

SC membrane *

2-6mmcleanstone

Aquaflowblocks

or slabs

Standardkerb block

SC intergrid *



Lowersub-base

10-63mmstone

Flow path to follow contour

Direction of slope

Dots indicate additional waterentering system through surface


must beshovel smooth

Uppersub-base5-20mm

stone



Forestedging

Standardblock

soldiercourse

Soft verge


2-6mmcleanstone

Inbitex *SC intergrid *


mm

80/6050

100

250

Forestedging

Standardblock

soldiercourse

Soft vergea 1:20 fall away fromthe permeable surfaceis required for at leastone metre.

*

*

Uppersub-base5-20mm

stone *

Inbitex evaporationcontrol membrane*

SC membrane


mm

80/6050

100

150

100

6mm pipebeddingstone

HeatingCoolingpipes



2-6mmcleanstone *

Standardkerbblock

SC intergrid *Concretehaunching


SC membrane

Formpave top hat seal

Pipework

1918

Sloping sites tanked systemAquaflow pavement with undersealing membrane also see plan

See specifications *

Illustrations on this page feature the Tanked system for Infiltrationreplace SC membrane with Inbitex.For further information contact theHanson Formpave design team.

Formpave top hat sealUnder normal conditions the top hat seal is tapedto the SC membrane. Where methane or a highwater table is present a fully welded seal isrequired and specialist advice should be soughtprior to installation.

Distribution TanksFor use in association with down pipe drainageinto a tanked system

Construction Drawingscontinued

Aquaflow paving in conjunction with Geothermal heat transferShown with the Standard Tanked system

Loops set in the

sub-base

Heating

The heat pump reversesits operation, extractingheat from the earth anddelivering it to thebuilding's HVAC system.

Cooling

Heat is extracted fromthe building andtransferred by the heatpump circulatingthrough the ground loop.

As water circulates, itgives up this heat intothe cooler earth. The cooled water thenreturns to the heat pumpto pick up more heat.

See specifications *


Soft landscaping and Aquaflow paving Recommended detail shown with infiltration system

Distribution TanksFor use in association with downpipe drainage into a tanked system

Material Polypropylene, Polyethylene,

PVC (connector)

Volumetric void 92 %

Effective perforated surface area 59 %

Compressive strength (1) 715 kN/m2

(unconfined)

Compressive strength (2) 1650 kN/m2

(confined in typical pavement,130mm cover)

Nominal size 354 x 708 x 150mm

Nominal volume 0.0375m3

Weight 3kg

Inbitex®

Thermally bonded nonwovendeveloped to optimise the cleansingof water entering the system. The various characteristics havebeen combined to create a uniquegeotextile that aids the developmentof the naturally occurringmicrobes, and offers them refugeduring periods of drought.

Mechanical properties

Wide width strip tensile EN ISO 10319

Mean peak strength 8.50kN/m

Elongation at peak strength 28%

CBR puncture resistance EN ISO 12236

Mean peak strength 1575N

Trapezoidal tear resistance ASTM D4533

Mean peak strength 325N

Hydraulic properties

Pore size EN ISO 12956

Mean AOS O90 0.145mm

Water flow EN ISO 11058

Mean flow VIH5010-3m.s-1 (l/m2.s) 80

Water breakthrough BS 6906: Part 3

Mean head 50mm

Air permeability ISO 9237

Mean flow 2875 l/m2.s

Typical physical properties

Mass EN 965 130 g/m2

Roll width 4.5 & 1.5m

Roll length 100m

Aquaflow ML: Include stretchercourse around edge in conjunctionwith MLE and MLTB.

KerbsStandard kerb system or ForestEdging: both to be haunched withconcrete.

Laying course*50mm depth of 2-6mm. singlesize clean crushed stone to BSEN 13242: 2002.

Inbitex® †As specification

Sub-base specification*All granular sub-base materialshall comprise crushed gravel,rock or concrete possessing welldefined edges. It must be sound,clean, non friable and free fromclay or other deleterious matter.

The material must be non plasticwhen tested in accordance withBS1377 Test No.4

* The crushed stone used for thelaying course and sub-base musthave a minimum 10% fines valueof 150kN when tested inaccordance with BS812 Part 111.

The selected test samples shall notbe oven dried and should be soakedin water at room temperature for 48 hours before the test.

The 100mm deep upper layer of sub-base material should begraded 5mm-20mm to BS EN 13242: 2002.

Grading of lower layer of sub-base stone:

BS EN Sieve size % passing 80mm 10063mm 90-10040mm 60-8020mm 15-3010mm 0-5

2120

† supplied by:

Aggregates are available through:

Hanson Aggregates

for further information phone

Formpave sales office

01594 836999

Inbitex® † and Distribution Tanks

Laying generallyAll construction work onpavements should be carried outfollowing completion of generalsite works and after topsoiling of adjacent areas to preventwash down of fine materials.Where a temporary running surfaceis required the construction shouldbe in accordance with diagram onpage 16.

Sub-gradeExcavate to sub-grade appropriatelevels shown on site drawings toprovide a minimum fall of 1:1000to fin drain. Where it is proposedto infiltrate no falls are necessary.

The sub-grade should becompacted with a vibrating plate orroller to the requirements ofClause 613 of the HighwaysAgency specification. Prior tocompaction all soft areas shouldbe removed and filled with suitablereplacement material to provide astable sub-grade.

Kerbs/EdgingsThe paved areas must be firmlyrestrained. Where the pavement isdesigned for heavy use the concretekerb haunching must extend to aminimum depth of 150mm belowthe base of the kerb.

The kerb/edging must extend with sufficient height above thehaunching to accommodate the fulllaying course depth and block height.

SC MembraneLay SC membrane taking care to overlap the joints by 300mmusing double sided tape. Wheresite conditions dictate that a water-tight system is required a fullywelded membrane will be necessary,specialist advice should be soughtprior to installation. If it isproposed to drain by infiltration tothe sub-grade, the SC membraneshould be replaced with ageotextile to stop the ingress ofsub-grade material into the sub-base. The fin drain will not berequired for infiltration designs.

Sub-baseThe lower layer of sub-base (10-63mm) should be placed in 2separate layers, each layer beingcompacted with a vibrating rolleror heavy duty vibrating plate to therequirements of Clause 802 of the Highways Agency specification.The final pass should beundertaken with no vibration.Compaction should continue until97% of the compacted bulkdensity achievable underlaboratory conditions has beenreached. This can be measuredwith a nuclear density gauge. The specified 350mm depth ofsub-base may be varied by theEngineer to suit site requirements.

SC IntergridWhere required the Intergridshould be incorporated at theinterface between the two layersof sub-base. The Intergrid shouldbe laid on the sub-base and jointsshould be overlapped by 300mm.

The upper sub-base layer (5-20mm) should then be laid ontop of the Intergrid and compactedas before.

A second intergrid can beincorporated underneath or withinthe sub-base at the engineersdiscretion. This should be laid inthe same way as the first intergrid.

Inbitex®

Lay geotextile on top of the sub-base overlapping joints by 300mm.Inbitex should be brought up tothe haunched kerb/edging andcut-off flush with the surface ofthe paving.

Laying courseLay and screed to level approximately50mm depth of 2-6mm singlesized crushed stone to BS EN13242: 2002. It is important thatthe final level of the 2-6mm stoneis accurate as the stone willcompact down much less thansand when the surface blocks arevibrated. The particle shape of

ConstructionQ24 Sustainable urban drainage system

115

Q24

telephone 0117 941 5480fax 0845 609 2525e-mail [email protected]

Geosynthetics Limitedtelephone 01455 617139fax 01455 617140e-mail [email protected]

Standard contract documentation To be read with preliminaries/general conditions

SUSTAINABLE URBAN

DRAINAGE SYSTEM

Aquaflow paving

TYPE(S) OF PAVINGPermeable concrete blockpaving

Manufacturer: Hanson Formpave Tufthorn Avenue, ColefordGloucestershire, GL16 8PRt 01594 836999 f 01594 810577

e-mail: [email protected]@[email protected]

web-site: www.formpave.co.uk

Reference Aquaflow, Aquaflow ML, MLE,MLTB, Aquasett or Aquaslab.

SizeAs per manufacturer's specification

ColoursRed brindle, Golden brindle,Natural, Charcoal, Burnt red. Aquasett available in Red brindle,Vendage, Traditional and Pennant.

Setting outAquaslab: Staggered stretcherbond with double stretcher coursearound all perimeters.

Aquasett: Staggered stretcherbond or 90o herringbone withdouble stretcher course around allperimeters.

Aquasett combined: Staggeredstretcher bond with doublestretcher course around allperimeters.

Aquaflow block: 90o herringbonewith double stretcher coursearound all perimeters.

Depth of Sub-baseIt is recommended that a sub-base depth of 350mm should beused. The depth of sub-base maybe varied at the discretion of theEngineer. Alternatively 270mm ofsub-base overlaid with 80mm ofdense bitumen base course toClause 903 of the HighwaysAgency Specification may be used.

Intergrid(s) † SC Intergrid.

DBM Running CourseTo be 20mm dense base bindercourse manufactured with 100/150grade bitumen to BS4987. The DBM shall conform with therequirements of BS 4987.

Membrane †Generally a taped membrane willbe suitable for most applicationsof the tanked system. If aguaranteed watertight system isrequired a fully welded systemshould be installed. Examples ofthis type of application would besites with a high water table,methane contamination, areasabove basements or retainingwalls. Further advice should besought from the HansonFormpave design team.

Fin drain †300mm Hydraway Fin Drain to BBANumber 95/85.

Seal † Formpave top hat seal

Sub-grade see details on page 6Where the structure is to be over-run by heavy vehicles thesub-grade should have, or beimproved to have, a CBR of atleast 15%. Poor sub-grades withlow CBR's may be improved byincorporating a capping layer ofcement, lime or bituminous boundmaterials. Alternatively granularmaterials in accordance withclause 613 of the HighwaysAgency specification may be used.

continued overleaf

2322

the 2-6mm stone will also affect the degree of compaction. It is recommended that a small trial area should be laid prior toconstruction to determine theaccuracy of final levels.

Block layingIt is advisable to pre-set the blocklevel by 6mm to allow for theeffects of settlement when laidagainst fixed edgings. The blocksand slabs must be tightly buttjointed ensuring that a good fit isachieved.

A single or double stretchercourse of Aquaflow blocks mustbe used around the periphery ofthe paved areas and also at theedges of any separately restrainedareas, such as tree pits.

It is recommended that lateralrestraints (such as forest edging)should be installed in areaswhere vehicles turn and/or brake,such as bends and junctions andon large areas of paving. Thelateral restraints should beproperly constructed andhaunched with concrete.Where blocks need cutting, theyshould be cut to a tight fit and noneare to be smaller than 30% of theunit block size with three machinededges. Where Aquaflow blocksare cut they must be cut acrossthe 100mm and not the 200mmdimension. Blocks should be cutvertically and not under-scored. All block cutting should be carriedout with a disc cutter.

Surface FinishThe blocks should be vibrated with a vibrating plate Type DVP75/22''or similar. Following the first passwith a vibrating plate, 2-4mmclean quartzite or gritstone shouldbe applied to the surface andbrushed in. (Available fromFormpave in 25 kg bags). The tapers and slots between theblocks should be fully filled. Blocksshould again be vibrated and anydebris brushed off.

Method of accessingservices and reinstatement

GeneralIt is important that access toservices in or underneath theFormpave Sustainable urbandrainage system is undertaken ina disciplined and progressive way.

ProcedureUplift Aquaflow blocks 1m eitherside of the line of relevantunderground services.

Take up the laying course stone and cut the underlying geotextilemembrane along either side ofthe line of services and parallelwith them. Dispose of the layingcourse stone and geotextile.

Excavate sub-base stone andplace adjacent to the excavationon plastic membrane. The sub-base stone can be re-used.

Cut intergrid(s) in the same wayas the geotextile and dispose of it.

Cut layer of geotextile orwaterproof membrane at reducedlevel along the line of the servicesin the same way as the higher layerof geotextile and dispose of it.

Excavate material over andaround services and put on plasticmembrane ready for re-use.

Carry out repair on services.

Once repairs have beencompleted replace and fullycompact the excavated materialaround the services.

Cut fresh geotextile or waterproofmembrane to size allowingadditional 300mm extra widtheither side of the remaininggeotextile membrane. Tape newgeotextile/membrane in place.

If a heavy duty welded waterproofmembrane is installed due to ahigh water table or the presenceof methane the replacementmembrane will need to berewelded to the existingmembrane.

Replace the first 250mm depth ofsub-base and thoroughly compact,cut and install fresh intergrid(s)allowing 300mm of extra widtheither side.

Spread and compact final 100mmdepth of sub-base.

Cut fresh geotextile membrane tosize again allowing 300mmoverlap using double sided tape.

Lay and loose screed to levelapproximately 50mm depth of 2-6mm crushed stone to BS EN13242: 2002.

Replace surface blocks, vibratesurface blocks to level and dressthe surface with 2-4mm cleangritstone and vibrate again.

Brush off and dispose of anydebris before final vibration.

Construction continued Colours and finishes

Colour and finish variationHanson Formpave products aremanufactured from naturallyoccurring materials andconsequently may show slightvariations in finish and colour.

It is strongly recommended thatproducts are taken from two ormore packs and mixed duringlaying to minimise any colourvariation.

All concrete products may sufferfrom efflorescence. This occursnaturally and will disappear withuse. It is in no way detrimental tothe performance of the product.No responsibility can be acceptedfor this natural reaction.

Alternative colours & finishesSpecial colours and finishes areavailable to order. Please contactsales office details.

SamplesSample blocks are available fromyour nearest Hanson FormpaveStockist upon request.

Charcoal Aquaflow and Aquaslab

Burnt Red Aquaflow and Aquaslab

Golden Brindle Aquaflow and Aquaslab

Natural Aquaflow and Aquaslab

Traditional Aquasett

Vendage Aquasett

EcoGranite Aquasett, Aquaslab and AquaflowNot available in Aquaflow ML, MLE or MLTB

Pennant Aquasett

Standard finish

Olden finish

Bush hammered finish

Colour reproduction

Every care has been taken to reproduce the colour ofthe blocks in this brochure as accurately as possible. However, we cannotguarantee the exact colourreproduction.

Standard finish

AquaslabAquaflow blocksAquaflow MLAquaflow MLE Aquaflow MLTB

Olden finish

AquasettAquasett combined

Bush hammered finish

to special orderAquasettAquaslabAquaflow blocks

Red Brindle Aquaflow, Aquaslab and Aquasett

24

Pack sizes and weights Formpave kerb options Maintenance

All packs are palletised and shrinkwrapped with the exception of theAquaflow block which is Voidpacked.

60mm Aquaslab 11.34m2 perpack, 84 blocks in 14 layers.Weight approximately 1.49 tonnesper pack.

60mm Aquasett 10.5m2 perpack, 280 blocks in 14 layers.Weight approximately 1.38 tonnesper pack.

80mm Aquasett 7.50m2 perpack, 200 blocks in 10 layers.Weight approximately 1.33 tonnesper pack.

60mm Aquasett combined11.2m2 per pack, 434 blocks in14 layers. Weight approximately1.47 tonnes per pack.

80mm Aquasett combined8.0m2 per pack, 310 blocks in 10 layers. Weight approximately1.42 tonnes per pack.

60mm Aquaflow block8.48m2 per pack, 424 blocks in14 layers. Weight approximately1.10 tonnes per pack.

80mm Aquaflow block5.92m2 per pack, 296 blocks in10 layers. Weight approximately1.04 tonnes per pack.

80mm Aquaflow EcoGraniteblock 8.0m2 per pack, 400 blocksin 10 layers. Weight approximately1.42 tonnes per pack.

80mm Aquaflow ML block6.5m2 per pack, 250 blocks in 10 layers. Weight approximately1.15 tonnes per pack.

80mm Aquaflow MLE block 52 lm per pack, 300 blocks in 10 layers. Weight approximately1.22 tonnes per pack.

80mm Aquaflow MLTB block80 lm per pack, 400 blocks in 10 layers. Weight approximately1.04 tonnes per pack.

The range of kerb optionstogether with the full range ofFormpave concrete pavingproducts are illustrated in greaterdetail in the standard Formpavemanual available on request.

Standard kerb systemThe range consists of fifteenblocks to facilitate edge restraint,cornering, cross-over and transition.

The surface blocks have a designlife equivalent to standard blockpaving.

All paved surfaces will requireoccasional cleaning. In normalcircumstances, regular sweepingwill be sufficient.

It is recommended that thisshould be carried out in the springand after leaf fall in autumn.

It should be noted that lightercoloured blocks may exhibit tyremarks and will therefore requiremore cleaning and maintenancewhen used in certain situations.

Following routine maintenance itmay be necessary to re-dress thesurface with 2-4mm cleangritstone.

Ultimately, perhaps after 25 yearsor more, areas of the layingcourse may become filled withsilts and toxins. If this occurs thesurface blocks should be upliftedand the affected areas of layingcourse material and geotextiledisposed of. The existing sub-base can be left in situ. Freshgeotextile and laying course stoneshould be installed and theexisting surface blocks re-used.

200100

100

15 radius

100100

50

150

200

100250

200

100

500

EcoGranite kerb Bush hammered finish.

Forest edging A substantial edge restraint also used for lateral strength in pavement design.

The system and products describedin this brochure are covered bypatents and patent applications inGreat Britain and other countries:

GB 2 294 077

GB 2 338 969

AU 42815/99

CA 2 334 571

EP 99942636.4

US 09/719,256

NZ 508 786

SG 77889

AU 2002217305

CA 2431 629

EP 1274092.4

NZ 526311

SG 200303346-1

US 10/450,764

ZA 2003/4637

GB 0406776.5

GB 99/01555

GB 99/01552

Formpave's policy of continuousproduct development maynecessitate changes to specificationswithout prior notification.

All drawings shown within thisbrochure are indicative only and notto scale.

All drawings and text are covered by copyright and may not bereproduced or transmitted in anyform without prior consent fromHanson Formpave.

Hanson FormpaveTufthorn AvenueColefordGloucestershire GL16 8PRtel 01594 836999fax 01594 810577

[email protected]@[email protected]

www.formpave.co.uk

Patents

© 2007 Hanson FormpaveColeford, England, UK.

Tufthorn AvenueColefordGloucestershire GL16 8PRtel 01594 836999fax 01594 810577

[email protected]@formpave.co.uk

www.formpave.co.uk

Hanson Formpave

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CDHanson Plc a Global Business

Hanson is one of the world'slargest suppliers of heavy buildingmaterials to the constructionindustry, with a turnover in 2006 of £4.1bn. Our products fall intotwo categories: Aggregates(crushed rock, sand and gravel,ready-mix concrete, asphalt andcement related products) andBuilding Products (clay bricks, pre-cast products and concrete pavers,blocks, tiles and pipes). We employ26,000 people, operating primarilyin North America, the UK andAustralia with further operations inAsia Pacific and ContinentalEurope. Hanson Building ProductsUK incorporates London Brick,Thermalite, Red Bank, Cradley andFormpave.

FM 12515

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