TreeBunker™ Tree Root Development System

A little bit about us..._______________

At Wrekin, we manufacture, supply

and can help with the installation

of landscaping systems, geotextiles,

geogrids and other ground

engineering products.

Our innovative approach to product

design and commitment to quality

and service has firmly embedded our

position as a market leader in civil

engineering solutions.

With more than 20 years of technical

expertise and leadership, we have a

extensive range of unique, patented

products to perfectly suit both

specifier and contractor.

A significant area of our business is

Geosynthetic products, which play

an integral role in the majority of

building, civil and marine engineering

projects. We offer Geosynthetic

solutions for ground stabilisation,

reinforcement, erosion control,

drainage, tree and grass protection

and weed suppression.

TreeBunker™ is a tree root

development system aimed at

managing and protecting tree roots.

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Create an urban forest_______________

Trees play a vital role in everyday life. Research has proven that trees with larger canopies provide more benefits to the environment. Until recently, growing trees in the current landscape in our towns and cities has proven a difficult task.

Structural soils (sand or rock based) have been used since the 1980s to provide trees in hardscapes with a balance of organic and structural material to build pavements and parking areas above the new rooting volume area. This has proven to be unsuitable for the longevity of the trees, which start with an initial growth spurt but then begin to die back very quickly due to the lack of available soil within the structural soil matrix.

Simple soil cells were introduced to the UK market in the late 1990s. Although basic in their design and perfomance, they paved the way for architects to design tree planting solutions with the tree as the main focus, and not the hard landscaping or street furniture.

Guidance is available from our specialist Geosynthetics team on 01543 440432 or via email at geosteam@wrekinproducts.com

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TreeBunker™tree planting system_______________The TreeBunker™ system is a modular void-forming container that provides unlimited expansion for unimpeded root growth, at the same time as supporting traffic loadings. It is ideal for new trees in areas such as pavements, car parks, plazas, green roofs and even green walls.

TreeBunker™ has a very highloadbearing capacity compared with similar void-forming structures. (Supported by independent testing and verification).

TreeBunker™ has been developed from the experience gainedby extensive trials, projectsand discussions with landscapearchitects, clients, contractors andnurseries to provide the most costeffective, fit for purpose solutionto the problems associated withgrowing large trees in urbanenvironments.

In addition to the key functions,such as withstanding heavytraffic loads, whilst maintainingpavement integrity and providing anunimpeded root growth, TreeBunker™ also promotes stormwater management within the system, dealing with rainwater run off at source, the ideal SuDS solution.

Key elements taken into consideration for the development process were the needof simple design, easy installation,sustainability, integration of existing and new utilities, variable unit depthand free void space available for soilinfill.

TreeBunker™ was developed from

the experience gained from trials,

projects and cooperation with

industry specialists.

Functions of TreeBunker™ System

• Carries heavy traffic loads

• Proves uninhibited root growth

• Rainwater retention

• Ease of installation

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Benefits of using TreeBunker™

• Variable system height, between 400mm and 1400mm.

• Designed to support heavy traffic loads whilst maintaining pavement integrity.

• Provides unhindered root growth for large species of trees.

• Quick and cost effective installation and easy to fill with any soil.

• Large spacing between legs of structure ensures roots will grow without being restrained.

• Made from 100% recyclable, long lasting and inert plastics.

• Modular system for design flexibility.• TreeBunker™ can be installed in curves

down to 5m radius without additional products.

• Utility friendly, designed for easy utility maintenance and repair.

• Combines storm water management and root growth, up to 25% of the volume is available for water infiltration.

• Up to 95% volume available for soil infill.• Withstands vertical and lateral loadings.

Time to makea difference...

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How TreeBunker™ TRD system works

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Surface to architects details

Upper sub base material (Usually MoT Type 1)

Root direction plate

Irrigation and Aeration cap

Anchored Tree ball

TreeBunker™ system

Loamy sand box infill material

Irrigation and Aeration system

Root-tex 10™ geotextile separation

Sub-base 100mm depth

Vertical geogrid to spread horizontal pressure

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Rootball anchoring method for loose soil application.

WREKIN PRODUCTS STOCK CODE ITEM DESCRIPTION DIMENSIONS

GSD/BUNKERFRAME MOULDED PLASTIC TOP AND BASE PANEL 600mm x 600mm

GSD/BUNKERDECK OCTAGONAL PLASTIC DECK GRID INSERT 540mm x 540mm

GSD/BUNKERPOSTS 100MM Ø POSTS TO REQUIRED LENGTH (X4 PER UNIT) Length x 100mm

GSD/BUNKERTRC30 TRC 30 REINFORCED LASER BONDED GEOTEXTILE 5m x 100m Roll

GTROOTTEX10 ROOT-TEX 10 NW GEOTEXTILE Various roll sizes available

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TreeBunker™ components

Our knowledgeable team has more than 20 years experience in developing solutions for protecting

trees. Call our technical sales department on 01543 440432 to find out more.

TITLE:

DRAWN BY:

DRAWING NO.:

DATE:

REVISON:

CHECKED BY:

SCALE:

CHRIS ECCLESTON

TRC30 REINFORCED

GEOTEXTILE

001-A

NOVEMBER 2016

N/A

ROY PARTINGTON

NOT TO SCALE

300mm

SUB BASE

EXISTING

WALL AND

FOOTING

ROOT-TEX 10

TREE

WREKINROOT BARRIER

TREE BUNKER

SANDY LOAM

TREE ANCHOR

TREE GRILLPOROUS PAVING

BEDDING LAYER

ROOT-TEX 10

SUITABLE

IRRIGATION

SYSTEM

ST JOHNS WOOD

TERRACE

KERB DETAIL

600mm

600mm

540mm100mm Ø

400mm

MIN. HEIGHT MAX. HEIGHT

1400m

Height can be manufactured to the required site specification.

Wrekin TreeBunker™ is a high strength load bearing underground container for large volumes of uncompacted soil for growing large species trees in hard landscapes in urban environments.

The unique design of the TreeBunker™ system allows for variable depths of units to be created very easily to meet the design requirements of the project or to meet actual construction constraints on site.

The units comprise of an injection moulded base plate, a top plate and a high strength deck. Four vertical connectors then link the base and top plates together to create the void-forming unit. The length of the connectors are variable; making TreeBunker™ the most flexible design solution available to the market.

Each modular unit measures 600mm (l) x 600mm (w) and interconnects with a lug / slot arrangement. The units are simply clipped together to meet the total volume of soil applicable to the tree. Whilst units can be connected, they can also be used with a 5cm spacing between the units.

TreeBunker™ has been developed to increase the soil volume afforded to new trees planted in hard landscapes (up to 95% of the area of each unit is available for infill) and to provide a structural platform, to build trafficked areas above, such as car parks and vehicular access areas.

This system now allows town planners,

landscape architects and arboricultural

professionals to confidently design large

trees into urban schemes without the fear

of structural failure of the pavement or early

decline of the tree.

The loading on the system can withstand

up to 15 tonne axle loads and is resistant

to vertical and lateral dynamic loading

forces.

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TreeBunker™ complete unit

Deck

TopPanel

Posts

BasePanel

Connecting lugs

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SuDSSustainable drainage systems (SuDS) are drainage solutions that provide an alternative to the direct channelling of surface water through networks of pipes and sewers to nearby watercourses.

By looking to nature for drainage regimes, SuDS aim to reduce surface water flooding, improve water quality and enhance the amenity and biodiversity value of the environment.

This is achieved by decreasing flow rates, increasing water storage capacity and reducing the transport of pollutants to the water environment.

The use of SuDS systems is increasing to meet environmental challenges such as climate change and population growth. Provision for SuDS and the national standards required for their design, construction, maintenance and operation is included in the Flood and Water Management Act 2010.

Sustainable urban drainage (SuDS)

Trees and Stormwater Management_______________Trees play an important part in managing the water cycle. Natural evapotranspiration accounts for approx. 70% of all rain water that falls on a tree. This, combined with 25% of the soil infill volume available for water management, means trees can play a vital role in eliminating costly SuDS packages.

Bioremediation, by filtration through the soil, treats rain water runoff providing a true source control solution.

Planting larger trees with large amounts of soil reduces flooding and the subsequent problems associated, such as erosion issues, polluting of water courses and of course, loss of property, with the possibility of further, more severe losses.

WaterUptake

FiltrationDetentionRetention

CanopyEvapotranspiration

Precipitation

Soil Respiration02 CO2

TreeBunker™ benefits

Benefits of big trees in urban landscapesLarge canopy, long living trees provide huge benefits to our environment. The obvious aesthetics are important but there are real tangible benefits such as:

• Increasing property values• Reducing the urban heat island

effect• Reducing building costs by

eliminating air conditioning• Improving population well being• Dealing with stormwater run off • Pollution control• Providing habitat for wildlife

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Trees need soilProviding large amounts of good, sandy, loamy soil for trees results in bigger, longer living and vibrant trees.

Bigger trees bring more benefitsTherefore, providing trees with the appropriate amount of soil required for them to achieve maturity is vital if we are going to cool cities and make them a more hospitable place to live.

Typically a tree with a canopy of approx. 10 metres requires 30 to 34m3 of uncompacted soil.

The only way to provide this soil volume in hard landscapes is to contain the soil in a structural module such as TreeBunker™.

More Soil = Bigger Tree

TreeBunker™ installation guide

1. Excavation the TreeBunker™ area

2. Install the Root-Tex 10™ geotextile

3. Quality Control

Excavate tree pit to engineers drawings.

Compact the bottom of excavation (sub grade) before placing fabric and sub base aggregate.

Place a layer of Root-Tex 10™ geotextile over the compacted subgrade. The geotextile is an important component of the overall system and it is essential for establishing a uniformly stable sub base.

Place the sub base aggregate over the geotextile. Compact the sub base aggregate to 95% standard proctor density or as specified.

It is the responsibility of the contractor through the Owner, Owner’s Representative, Engineer, or Geotechnical Consultant to verify that the sub base is constructed to the specified requirements prior to placing any TreeBunker™.

4. Mark out the bases

Mark out the inner dimensions of the tree opening using a suitable method.

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5. Lay out the bases

Place the frame around the treepits and beyond the tree opening and space accordingly.

If TreeBunker™ frames are not linked horizontally, then use the pins to anchor the frames to the base. Use a minimal of 2 pins per frame.

6. Attach the posts to the base frame

Insert 4 posts per panel and repeat as necessary.

Place top frame on top of posts.

7. Install the TRC 30™ reinforced geotextile

Install TRC 30™, a reinforced geotextile, around the perimeter of the TreeBunker™ System.

TRC 30 keeps the soil inside the system without pre-venting movement of water and air in and out of the system. Allow for a >150mm overlap at the bottom. At the end/beginning allow an overlap of >500mm.

8. Install the first lift of backfillIn order to keep the grid in place, tie TRC 30 to units during backfilling. Compact the backfill material around the perimeter of the installation in 200mm maximum layers.

TreeBunker™ installation guide

9. Closing the system

10. Install the tree pit kerbing

11. Install and compact the aggregate base course

12. Install the permanent pavement

1. Level out the soil. Leaving an air layer between 30mm and up to 80mm.

2. Clean the frames.3. Attach the decks. 4. Install the geotextile fabric over the TreeBunker™

Install the tree pit kerbing using either prefabricated or poured in situ concrete slabs.

Install the root guide panels inside the tree opening to assist the tree roots in locating the uncompacted soil in the TreeBunker™ system

Cover completed TreeBunker™ system with the specified back fill material, rolled and compacted in accordance with standard engineering practices.

Please refer to architects specifications.

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Design and technical support

Wrekin are pleased to offer design assistance from concept, through all stages, to project delivery.

We can assist in the selection of soil volume required for specific tree species and Wrekin also cooperate with Tree professionals to advise on Right Tree Right Place, ensuring the correct species is specified for the area of the design.

We provide standard CAD drawings and site specific as built drawings when required.

As part of our customer service chapter we also supervise the installation of the TreeBunker™ system to ensure the client is delivered the vision set out during the design stage.

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Guidance is available from our specialist

Geosynthetics team on 01543 440432

or via email geosteam@wrekinproducts.com.

Notes:

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Other products from Wrekin:

Geogrids TurfmeshAsphalt Reinforcement Grids

Geomembranes

Grass / Gravel Paving Systems

Gabion Baskets

CellPave HD

Woven & Non Woven Geotextiles

Geocomposite Drainage

Intelligent products for civil engineering

Wrekin Products LimitedEuropa WayBritannia Enterprise ParkLichfieldStaffordshireWS14 9TZ

01543 440440

01543 440444

www.wrekinproducts.com

@wrekinproducts

wrekin products