Watershell Catalogue Specto Ct August 2009

Specto Civil Technology Inc. | T (604) 287 4327 | F (604) 287 4343 | [email protected] | www.watershell.ca � /v2.0

Specto Civil Technology Inc.’s catalogue contains our range of Watershell storm water management products. You will find detailed product descriptions as well as tender details, example drawings and reference projects. Specto Civil Technology Inc. is always available for advice and support during the design stages of your projects.

Specifications and drawings are subject to change without prior notice as we continue to develop our products.

© All rights reserved. No part of this publication may be reproduced in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior written permission of Specto Civil Technology Inc..

Registered trademark Watershell® is owned by Waterblock BV, Zundert, The Netherlands. Specto Civil technology Inc. is the official Waterblock BV Distributor in North America.

Introduction

Specto Civil Technology Inc. | T (604) 287 4327 | F (604) 287 4343 | [email protected] | www.watershell.ca

Contents

Catalogue - Watershell 2

- XPE Foam 4

1 Watershell modules 4 – 55 - Work description 5

1.1 Watershell modules installation 5

1.2 Concrete specification 6

1.3 Concrete pouring method 7

2 Watershell Atlantis - Work Description 8

2.1 Watershell Atlantis installation 8


2.3 Concrete pouring method 13

3 Infiltration Field – Summary 15

Infiltration Field – Projects 16

Infiltration Fields – Work Description 26

3.1 Preparation 26

3.2 Geotextile installation 28

3.3 Tile installation 28

3.4 Modules installation 29

3.5 Concrete reinforcement installation 29

3.6 XPE board installation 30

3.7 Installing inlet/ outlet pipes and inspection manholes 31

3.8 Backfill 32


Infiltration Field – Step by Step Work Description 34

Infiltration Field – Tender Description 36

Infiltration Field – Drawing Example 38

4 Infiltration Cellar - Summary 39

Infiltration Cellar – Projects 40

Infiltration Cellar – Tender Description 45

Infiltration Cellar – Drawing Example 48

5 Water Storage Cellar – Summary 49

Water Storage Cellar – Projects 50

Water Storage Cellar – Tender Description 60

Water Storage Cellar – Drawing Example 62

6 Root Bridge – Summary 63

Root Bridge – Projects 64

Root Bridge – Tender Description 68

Root Bridge - Drawing Example 70

7 Tree Environment Protection – Summary 71

Tree Environment Protection –Projects 72

Tree Environment Protection – Tender Description 79

Tree Environment Protection – Drawing Example 81

8 Light Weight Backfill – Summary 82

Light Weight Backfill – Projects 83

Light Weight Backfill – Tender Description 89

Contents

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B L h H weight concrete Nett capacitycm cm cm cm kg/pc m3/m2 m3/m2

50 x 50 10 3 4 0.770 0.004 0.036

Pallet 110 x 110 cm Applicationsmax height weight # of area • drainage

• raised floorsm kg pieces m2

1.10 310 400 100


50 x 50 26 4.5 8 1.240 0.012 0.063

Pallet 110 x 110 cm Applications

max height weight # of area • root bridge• drainage• raised floors

m kg pieces m2

2.50 490 400 100


50 x 50 31 8 12 1.250 0.016 0.073



m kg pieces m2

2.50 500 400 100


50 x 50 31 11 16 1.300 0.034 0.105



m kg pieces m2

2.50 400 300 75

Watershell 4 - item # 2004




Watershell is a plastic dome shaped module with fixed width and variable height. The modules create formwork for concrete pouring. Due to its unique dome shape and ingenious joints a concrete construction arises with columns spaced every 50 cm. A large cavity underneath the modules forms after concrete has hardened. The large number of columns makes for a structure with very high load bearing capacity using a minimum of reinforcement and concrete. The modules can be used as infiltration fields, infiltration cellars, root bridges, tree root environment protection, lightweight backfill and raised floors. Watershell module measurements:

Catalogue - Watershell

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50 x 50 33 13 20 1.450 0.035 0.140


max height weight # of area • infiltration• water detention• raised floors

m kg pieces m2

2.50 450 300 75


50 x 50 34 21 27 1.650 0.040 0.205



m kg pieces m2

2.50 510 300 75


50 x 50 30 29 35 1.850 0.056 0.269



m kg pieces m2

2.50 570 300 100


50 x 50 32 34 40 2.000 0.060 0.315



m kg pieces m2

2.50 620 300 75


50 x 50 35 39 45 2.100 0.065 0.350



m kg pieces m2

2.50 650 300 75


50 x 50 35 44 55 2.400 0.090 0.395


max height weight # of area • Tree root protection• water detention• raised floors

m kg pieces m2

2.50 730 300 75










50 x 50 31 11 16 1.500 0.034 0.105

Pallet 110 x 110 cm Applicationsmax height weight # of area • infiltration/water detention

• tree root protection• raised floors

m kg pieces m2

2.50 460 300 75

Watershell Atlantis 16 - item # 2016A

Watershell Atlantis Column Base Support - item # 20CBS

Watershell Atlantis System

max height weight # of area The column base is used to support the columns when using the Watershell Atlantis system. The column base stabilizes the system and prevents concrete spills. De-aeration slots provide an escape for trapped air.

m kg pieces m2

2.50 460 300 75


height column height pipe cutoff length concrete Nett capacitycm cm cm m3/m2 m3/m2

75 59 58 0.055 0.673

100 84 83 0.064 0.913

125 109 108 0.073 1.154

150 134 133 0.082 1.394

175 159 158 0.091 1.635

196 (max.) 180 179 0.099 1.837


Catalogue - XPE BoardXPE Board Standard thickness (T): 35 mm (tolerance -0/+5mm)

Standard non woven geotextile: 150 grams Class IIIStandard sizes: Board, 1 x 2.25 m Roll, 1 x 10 m. Roll, 2 x 65 m. (tolerance on length and width -0/+3%)

RecyTop - item # 20.RT35

Application• Drainage and protection• Horizontal drainage grooves for extra drainage• Standard 15 grooves

S-Foam - item # 20.SF

Application• Protection and attenuation• Flat surfaces• Higher compaction than RecyTop for better attenuation

NetFoam - item # 20.NF25

Application• Protection• One side has a HDPE mesh for higher strength and better point load distribution

Layered product:1. Geotextile2. Mesh3. Foam


1 Watershell 4-55 – Work Description

Fig.1: Modules positioning pattern, leFt to right, arrows in one direction

1. Watershell 4-55 - Work description

1.1 Watershell modules installation

Install the modules working from left to right, pointing the arrows on the modules in the same direction (fig.1). Follow the modules’ indicated installation pattern. The modules’ rims overlap and connect to create a strong solid form. To avoid height differences between the modules, the modules’ legs should be joined together consistently and placed on a level floor.


1.2 Concrete specification

After installing the modules the formwork is ready to be filled with concrete. It is very important to calculate the amount of concrete needed. Concrete is poured into the formwork’s columns and on top of the modules to create the structure.

Concrete specification for Watershell modules (Watershell Atlantis System excluded):

• Concrete strength C20/25 mpa• S3 consistency• Granular stone Ø 4 – 32 mm with max Ø = 32 mm• Chloride grade CL 0.40 reinforced concrete

The concrete cover layer will vary in thickness, steel reinforcement and concrete quality, dependant on environment, load-bearing capacity and system geometry. Expansion joints may be needed and have to be taken into account. Contact your local Watershell supplier for more information and/ or engineering questions.

The amount of concrete needed to fill the formworks’ columns to the top of the modules depends on the modules’ height. Table 1 depicts the amount of concrete in cubic metres needed with various Watershell modules, excluding the amount needed for the concrete cover layer.

Watershell height cm Concrete amount m3

16202735404555

0.0340.0350.0400.0560.0600.0650.090

table 1: concrete aMounts in coluMns between Modules

For example:

The total amount of concrete needed with Watershell 45 and a flooring of 100 mm thickness: 0.065 m3/m2 + 0.1 m3/m2 = 0.165 m3/m2



1.3 Concrete pouring method

It is important to start pouring concrete in the middle of the floor in the centre of the module. Do not pour concrete directly into the columns, but fill them from the centre of the modules at all times. Work from the centre of the floor outwards concentrically (fig. 3). When using a concrete pump make sure the flow is slow and consistent, preferably using the hose horizontally. Finish the floor and make sure to avoid shrinkage of the floor after pouring.


Start pouring herecontinuing in direction

of the arrows

Fig. 2: concrete pouring pattern


2. Watershell Atlantis Work description

2.1 Watershell Atlantis installation

The Watershell Atlantis system differs from all other Watershell modules. The Watershell Atlantis system consists of 500 mm x 500 mm dome shaped modules 160 mm in height. The connected Atlantis modules form a concrete formwork system. Rigid pipes with a 110 mm Ø on a 500 mm x 500 mm grid carry the formwork system. The pipes’ lower ends are capped of with the Watershell Atlantis column base supports (fig. 3). After concrete pouring the system has a raised concrete cover supported by concrete columns.

Fig.3: watershell atlantis systeM with Modules, coluMns and coluMn base support.

2 Watershell Atlantis – Work Description


Installation conditions:a) Construction length (L) and width (B) are multiples of 500 mm + 150 mm, as follows: Length: L = Nl x 500 mm + 150 mm, Nl = number of modules lengthways Width: B = Nb x 500 mm + 150 mm, Nb = number of modules sideways For example (fig.3): L = 7 x 500 + 150 = 3650 mm and B = 5 x 500 + 150 = 2650 mm

b) Maximum inner height of the system is 1960 mm, with 1800 mm pipe columns and 160 mm column supports. Fig. 4 shows a pipe cutoff length of 1490 mm.

Fig.4: pipe coluMns MeasureMents, MaxiMuM inner height 1960 MM.

2 Watershell Atlantis– Work Description

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Install modules working from left to right, pointing the arrows on the modules in the same direction (fig.1). Follow the modules’ indicated installation pattern. The rigid plastic columns have a 110 mm diameter and a 2 mm (max.) wall thickness and need to be cut to length perpendicularly, leaving smooth and clean edges. The modules’ corner rims lock around the pipe. The column base support is used to create columns with the Watershell Atlantis system. The column base support stabilizes and supports the system and prevents concrete spills. De-aeration slots in the column base supports make for excellent density.

Modules can be cut lengthways and refitted to size (fig.5).

Fig.5: Modules can be cut and reFitted to size


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Modules can be cut and refitted to size even alongside an angled wall. To support the refitted modules, 110 mm Ø holes are cut into the modules alongside to fit in the plastic columns. Secure the columns in the holes with stainless steel wires (fig.6).

Fig.6: extra coluMns with angled walls



Expanded Polystyrene (EPS) insulation (100 mm (L). x 70-100 mm (W)) is used to fill the gap between the Watershell Atlantis system and the system wall. Close any gaps with expanding foam (fig.6).Larger projects can be fitted with cast in place holes to accommodate manholes, lids or covers to access the Watershell Atlantis systems’ cavity. This way the Watershell Atlantis system is fully inspectable and cleanable. These manholes usually measure 800 mm x 800 mm and are placed on a 8 by 8 grid of columns (fig.7).

Fig.7: installation oF a 800x800 MM exclusion ForM in concrete Floor



2.2 Concrete specifications

After installing the modules, the system is ready to be filled with adequately flowing concrete. Concrete is poured into the formwork’s columns and on top of the modules to create pedestal or raised flooring.

Concrete specification for Watershell Atlantis modules (columns to top rim of modules):

• Concrete strength C28/35• Consistency: F5, fluid• Granular stone Ø 4 – 16 mm, max Ø = 16 mm• Chloride grade: CL 0.40 reinforced concrete

Use S3 or S4 concrete consistency for the top flooring with a max. granular Ø of 32 mm. Steel mesh reinforcement is to be placed on top of spacers. The necessary amount of concrete per m3 per m2 needed in a project is calculated with this formula:


s/10000.034

h/1000 x 0.036

m3/m2

m3/m2

m3/m2

Floor thickness on top of modulesAmount in Watershell modulesAmount in pipe columns

(s/1000) + (0.034) + (h/1000 x 0.036) m3/m2 Total amount

Concrete on top of the system outer walls has not been taken into account (fig. 4).

2.3 Concrete pouring method

It is important to start pouring concrete in the middle of the floor in the centre of the module. Do not pour concrete directly into the columns, but fill them from the centre of the modules at all times. Work from the centre of the floor outwards concentrically (fig.8). Compact concrete to specification, but avoid using poker vibrators, especially inside the columns. Make sure to avoid shrinkage of the concrete floor after pouring.


Fig.8: concrete pouring diagraM


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Flood prevention, runoff water reuse and storm water management are important issues in environmentally sustainable urban developments. Watershell Infiltration systems offer flexible solutions to every storm water project. Runoff water is temporarily stored to reduce and mitigate the total runoff volume and maximize the amount of runoff returned to shallow groundwater via recharge. It maintains pre-development flow regimes, surface water quality and local temperature ranges as well as restricts post-development peak runoff flow-rates to that of the pre-development stage. Infiltration systems are built in under parking lots, squares, roads and parks.

Infiltration Field Advantages:

• Simple and fast installation• Inspectable and cleanable• High load bearing capacity• No backfill needed• Variable area, L x W x H• High water bearing capacity up to 401 l/m2

• Relatively low cost• Multiple use of space• Large infiltrating area• Low volume transport• Applicable with high groundwater levels• Great expertise and many reference projects

Fig.9: watershell inFiltration systeM drawing exaMple

Notices, please consider:

• Watershed area• Runoff water quality• High peak runoff amount• Groundwater levels (G.W.L.)• Ground permeability• Dissipating speed• Available space• Traffic load• Ground cover• Earth pressure allowance

Watershelltype

load bearingcapacity

kN

concreteD. floor

mm

thicknessD. tilemm

outer heightmm

water bearing capacitym3/m2

Watershell 27Watershell 27Watershell 27

none450600

80120120

458080

395470470

0.2340.2560.256

Watershell 35Watershell 35 Watershell 35

none450600

80120120

4580�0

475550550

0.2980.3200.320

Watershell 45Watershell 45Watershell 45

none450600

80120120

458080

575650650

0.3790.4010.401

Contact your local Watershell system supplier for more information and/ or engineering questions.

3 Infiltration Field - Summary


3 Infiltration Field - Projects

Principal: MunicipalityArea: 50 m2

Water bearing capacity: 20 m3

Load bearing capacity: 450 kNMaterial: Watershell 45

Geotextile, concrete tiles and Watershell modules Length 10 m x width 5 meters

Inlet pipe for storm water Installing spacers and steel mesh concrete reinforcement

To accommodate water by-laws in an urban area the storm water has to be diverted from the sewer system. Storm water from roof tops and streets is collected and diverted into the Watershell infiltration system. Storm water dissipates into the sub soil at a controlled rate. The amount of time it takes for the system to totally infiltrate is dependant on the permeability of the surrounding soil.


Principal: IKEAArea: 5,000 m2

Water bearing capacity: 1,940m3


Installing the modules System overview

Pouring concrete Load bearing within a week

IKEA built a new facility on 7.4 acres. The storm water amount generated from the impermeable surfaces and the roof exceeded the amount the streams and canals could handle and by-laws didn’t allow for this type of water to be dumped into existing open waters. IKEA had to come up with a solution for the storm water issue. The solution presented to them was to create a 4 m x 130 m infiltration system underneath the parking lot using the Watershell system. Storm water collected from the parking lot and the roof is redirected into the infiltration system. Storm water slowly dissipates into the sub soil. The system is able to accommodate peak rainfall and store up to 1,940 m3 of water at a time.






Installing the Watershell modules Steel mesh or rebar

Overview of the 500 m2 system Pouring concrete

This Municipality has chosen to divert storm water from the sewer systems. As the permeability of the soil is very good they wanted a large infiltration system that could contain the water so it can dissipate into the soil. The finished system has a water bearing capacity of 720 liter/m2 because of the soil conditions. The system built also had to accommodate the Municipality’s garbage facility and withstand heavy loads like trucks and containers.






Installing the Watershell modules Inlet

Modules with steel mesh and drainage material Finished flooring

When building new housing accommodations for a municipal institute, storm water from the roof tops and parking lots had to be collected and stored underground to accommodate infiltration. The solution was found by building a network of Watershell infiltration units under the parking lots. This configuration allowed the storm water to dissipate within 12 hours after collection.


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Modules installed in different configurations Column top view

Sand between the fields accelerate dissipation Project overview

During the construction of a sub division the contractor had to build an infiltration system. The object of the system was to create water balance between pre- and post-development stage. After completion of the infiltration system the contractor used the concrete surface as a parking lot and area to store material. In the end phase of the project the system was covered with a park and a square keeping the system accessible.


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Manhole cover for accessibility and to collect water samples

CCTV-inspection of the infiltration system

Images taken from inside the system Images of the Watershell modules

This municipality built a storm water infiltration system under a large square. The system is constantly monitored and the water quality is tested at regular intervals. A key component of monitoring is a CCTV inspection. The system can be accessed via a manhole cover and the camera can be lowered into the system. This infiltration system was built underneath a basketball court.


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Installing modules on a crushed lava stone foundation Drainage material as a perimeter

Infiltration system is the foundation for a bicycle path Pouring concrete

In a new suburb development the Municipality had a railway system installed. The storm water collected on the roof and parking areas around the railway cannot be connected to the sewer system or dumped into open water. The storm water is redirected into the Watershell system and a crushed lava rock foundation doubles as a filter system for the runoff water. This purified water can dissipate into the sub soil without causing an environmental risk.






Positioning of the modules Materials storage

Sand in between the systems Pouring concrete

Within this Municipality it is mandatory to compensate the amount of impermeable surface area due to construction of roads, parking lots or buildings by creating underground storm water storage. This water has to be used to replenish the ground water table. The system was constructed 1.6 m below the surface to accommodate a gravitational flow of storm water into the system. The system doubles as a ground water drainage system in Winter and an infiltration system in Summer.



Principal: Church Area: 113 m2



Positioning the modules Installing the rebar mesh

Infiltration system on the church grounds Cross section of the Watershell system

The Bishopdom requested a solution for their storm water problem. Water that came off of the roof of the Cathedral contained large quantities of lead and copper elements. The church was required to filter this polluted water and try and infiltrate the clean water into the sub soils. The solution was found by placing the Watershell system on a foundation of crushed lava rock. The lava has an excellent filter quality. The polluted storm water runs into the infiltration system and the water is purified. The system was built underneath the church’s lawn.



Principal: Land DeveloperArea: 2,050 m2



Digging the trench Installing the Watershell modules on a geotextile

Installing the reinforcement mesh System is ready for concrete pouring

A Land Development Company was building its office and maintenance buildings on 7.4 acres. To comply with the municipal by-laws concerning urban runoff water the Land Developer had to build a storm water infiltration system large enough to contain 800 m3 of runoff water. The contractor wanted three separate infiltration systems each suitable for bearing heavy loads. Two systems of 240 m3 each and one system of 318 m3 were built. Each system has an overflow in case it exceeds the maximum water bearing capacity. The overflow is forced out of the system and flows over the road into the sewer system. This method of monitoring was chosen so it would be easily detected when an overflow occurred.



3 Infiltration Field - Work Description

3.1 Preparation

Surveying specifications and considerations:

• Use the most recent version of Call-Before-You-Dig data to localize any underground utility infrastructure.• Investigate load bearing capacity of the excavation for construction’s sub base and improve soil conditions and/ or change construction to specification• Investigate soil permeability conditions to calculate the hydraulic conductivity (K) of the soil and dissipating speed• Investigate groundwater conditions; to guarantee maximum infiltration field capacity, the system has to be build above average groundwater level (GWL)

Installing:

• Excavation for construction’s outer measurement is 0.50 m wider than outer measurements of the Watershell infiltration field• Length (L) and width (W) of the infiltration field are in multiples of 0.50 m + 0.12 m. These 0.12 m consist of the modules’ rims (2 x 0.02 m) and XPE-foam (2 x 0.04 m) on the outer edges of the field• Module height is variable, e.g. 27, 35, 40 and 45 cm• Pouring concrete thickness and quality vary dependant on load bearing capacity needs and ground cover• The steel rebar mesh used is equally spaced crossed bars with a 6-100-100 mm diameter, but can differ according to specification of the engineered construction and/ or the producer of the steel mesh reinforcement.

3 Infiltration Field - Work Description


Fig.10: cross-section oF the inFiltration Field

3 Infiltration Fields - Work Description

Fig.11: top view oF the inFiltration Field



3.2 Geotextile installation

The recommended geotextile Mirafi® HP370 or HP570 is installed on a sufficiently load bearing and water permeable floor. This floor is fully prepared and equalized on the engineered depth with ± 1 cm allowance. The total area of the geotextile is Length x Width (LxW) plus 4x Height of the XPE foam board plus 0.5 m on every side. This way an overlap is created on the perimeter of the infiltration field, thus avoiding sand leaching into the field (fig.12).

Fig.12: geotextile’s overlap around outer tiles and xpe FoaM board

3.3 Tile installation The concrete tile’s thickness can vary from 45 mm to 80 mm dependant on the required load bearing capacity of the infiltration field. The centre of the first tile is installed at the corner of the first Watershell module, overlapping length and width wise (fig.2). Install tiles centre to centre every 50 cm. TIP: use a piece of cut to size board as a spacer template. On location of the inlet pipe tiles have to be installed connected forming a solid apron of at least 1 m2, thus preventing leaching of sand (fig.13).

Fig.13: the bottoM right corner oF the systeM shows connected tiles at the site oF the inlet


3.4 Module installation

Install modules from left to right, pointing the arrows on the modules in the same direction. Follow the modules’ indicated installation plan. Pay special attention to assembling the legs of the modules, they should always interlock.

Fig.14: Modules installation plan, leFt to right, arrows in one direction

3.5 Concrete reinforcement installation

Steel mesh reinforcement (Ø 6 x 100 x 100 mm) is installed using spacers on top of the modules with a minimum of 250 mm overlap. If the infiltration field is subject to high traffic loads and ground cover is limited, reinforcement of corner and or rim modules is advisable. After the installation of the steel mesh, the structure is more stable and easier to walk on. The XPE board is installed after installing the steel mesh. The steel mesh needs a spacing of 40 mm in reference to the XPE board to ensure sufficient concrete cover on the perimeter (fig.15).

Fig.15: spacing oF the steel Mesh in reFerence to the xpe board with geotextile


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3.6 XPE board installation

The XPE board ensures water is infiltrated into the surrounding soil and prevents sand leaching into the system. XPE board is an essential part of the Watershell system and can not be replaced by other materials. XPE board consists of recycled expanded polystyrene with a thin layer of geotextile on one side and a green reinforcement mesh on the other. Its length is 1000 mm and its height varies dependant on the height of the system (module’s height + concrete cover). Its thickness is 40 mm. The green mesh side of the XPE board is installed on the outside of the field, the joints are installed at the leg/ column of the modules, thus ensuring maximum earth pressure resistance (fig.16).

Fig.16: installing oF the xpe board’s joints at the Module’s coluMn

As mentioned in chapter 2, the geotextile around the system is installed around the outer tiles and between the XPE boards and the modules. Modules on one side and sand footing on the outside support the XPE boards. Just use your feet to create the sand footing (fig.17).

Fig.17: xpe board, green Mesh on the outside, supported by sand Footing



3.7 Installing inlet/ outlet pipes and inspection manholes

After installing the XPE board barrier connecting pipes and holes are installed. The system can include inlet, outlet, de-aeration/ venting and overflow pipes. To seal of pipes and XPE board a combination of polyurethane foam and concrete is used. An XPE board box is placed around the pipe entrance spaced at 15 cm and sealed of with foam forming formwork to be filled with concrete. This creates extra stability around the pipe’s inlet/ outlet (fig.18).

Fig.18: installing ForMwork For pipe inlets/ outlets

For easy access and inspection, formwork holes are installed in the system’s concrete cover to accommodate manholes, see fig.19. Inspection and maintenance are essential characteristics of the Watershell Infiltration fields.

Fig.19: Manhole For visual inspection and systeM Maintenance



3.8 Backfill

First backfill the perimeter to half the modules’ height to prevent shifting of the modules, then loosely backfill to the rim of the XPE board. Walking on the systems backfill at this stage is strongly advised against, the modules could shift. Backfill material is water permeable sand (fig.20).

Fig.20: loosely backFilled periMeter prior to concrete pouring

3.9 Concrete specification

After backfilling the side face, concrete can be poured into the structure. It is important to calculate the concrete amount needed to completely fill up the system’s columns formed by the module’s legs and the concrete top cover. Essential attributes of the concrete are:

Concrete specification for Watershell modules (Atlantis excluded):

Strength: C20/25Grade S3 plasticityGranular stone Ø 4 – 32 mm with Dmax Ø = 32 mmChloride grade CL 0.40 reinforced concrete

The concrete cover varies in thickness, steel mesh and concrete quality dependant on environment, loading and geometry of the construction. Expansion joints have to be taken into account, follow the structural engineer’s directions. Contact your local Watershell supplier for more information and/ or engineering questions.

The amount (m3 per m2) of concrete needed to fill the formworks’ columns to the top of the modules depends on the modules’ height. Table 2 depicts the amount of concrete in cubic meters needed with various Watershell modules, excluding the amount needed for the concrete cover.



Watershell height cm Concrete amount m3

27354045

0.0400.0560.0600.065

table 2: concrete aMount per watershell height cM

It is important to start pouring concrete in the middle of the floor in the centre of the module. Do not pour concrete directly into the columns, but fill them from the centre of the modules at all times. Work from the centre of the floor outwards concentrically (fig.21). When using a concrete pump make sure the flow is slow and consistent, preferably using the hose horizontally. Finish the floor with a trowel. Make sure to avoid shrinkage of the concrete floor after pouring.

Fig.21: < concreting the coluMns > concrete pouring pattern



1. Excavate the area needed to build the system, use a compacted layer of sand for adequate load bearing capacity.

2. Install geotextile and space the concrete tiles according to specification

3. The Watershell System must be positioned with the columns on the tiles.

4. The XPE drainage mat is placed around the perimeter and secured in place with sand.

5. The woven geotextile must be wrapped around the XPE mat.

6. The steel reinforcement mesh is placed on top of spacers before concrete pouring.

3 Infiltration Fields - Step by Step Work Description


7. Inlets and outlets are created using the XPE board to box in the pipes. In the detention system create an apron with tiles at the inlet’s position.

8. Backfill the perimeter with sand and compact lightly.

9. Pour the concrete on the modules at a controlled rate either with a concrete pump or excavator.

10. Fill the columns with concrete.

11. Trowel the concrete to create a smooth surface. The system is ready for use after the concrete has hardened.

3 Infiltration Fields - Step by Step Work Description


Infiltration cellar advantages:

• Simple and fast installation• Accessibility• Inspectable and cleanable• High load bearing capacity• No need for ground backfill• Variable height, length and width• High volume storage capacity• Relatively low costs• Multiple space plan• Large infiltrating surface area• Great expertise and many reference projects

4 Infiltration Cellar - Summary

Sustainable development strategies are of great influence in new developments, constructions and restructuring projects. Communities—large and small, rural and urban—are facing many challenges associated with sustainable development, whether building houses, office buildings, industrial areas or infrastructure projects. The underground construction of infiltration cellars may help to meet a number of challenges. Runoff water is temporarily stored in the Watershell system and can dissipate either back into the soil, the sewer system or surface water at a controlled rate. Infiltration cellars’ application possibilities are endless, for example beneath parking lots, squares, roads and green belts.


• Connected surfaces• Runoff water quality• Peak rainfall quantity• Ground water level (GWL)• Effluent rate• Sediment or leaf traps• Available area• Traffic load• Ground cover/backfill• Allowed earth pressure

Watershelltype

load bearingcapacity

kN

concreteD. floor

mm

thicknessD. tilemm

outer heightmm


AtlantisAtlantis

12501250

450600

120��0

120150

0.6820.634

AtlantisAtlantis

12501250

450600

120��0

120150

0.9230.875

AtlantisAtlantis

12501250

450600

120��0

120150

1.1631.115

AtlantisAtlantis

12501250

450600

120��0

120150

1.4041.356

AtlantisAtlantis

12501250

450600

120��0

120150

1.6441.596

Values are based on 600 mm ground coverage, Ø 8 x 150 x 150 steel mesh reinforcement and sufficient load bearing capacity of the systems floor. Ground coverage of less than 600 mm can influence reinforcement and/ or concrete D values. Please contact your local Watershell system supplier for more information and/ or engineering questions.


Principal: Shipping CompanyArea: 783 m2


Load bearing capacity: 600 kNMaterial: Watershell Atlantis

4 Infiltration Cellar - Projects

Positioning the modules Overview system

XPE Drainage material installed along perimeter Pouring concrete

A shipping company needed to build a large retention buffer on their premises. The contractor build a cellar to retain storm water from roads and roofs. The storm water is buffered for a short period and then disposed off via the storm sewer system. The cellar was built to accommodate 925 m3 of storm water to avoid water problems during a rain cycle. The cellar has an external height of 1.5 m and the sides were created using L-shaped retaining walls with XPE RT35 drainage mat around the whole perimeter. The mat was used as an infiltration layer to replenish the surrounding soil. Watershell Atlantis was placed on a concrete floor without rebar. The system was built with a 12 cm concrete cover. The chamber was built under the company’s parking lot and has a 600 kN load bearing capacity, which is comparable to a traffic load of a truck with three axles weighing 200 kN each.





L-shaped retainer walls and concrete floor Manhole with sedimentation trap and controlled effluent

Overview infiltration chamber Overview after installing the modules

Near a retirement home a large infiltration system was built underneath the access road. The system has a capacity of 380 m3 and a Nett water bearing capacity of 1,086 ltr/m2. The Watershell Atlantis system was built on a reinforced concrete floor between a 1.5 m high retaining wall. The concrete cover of the system was constructed using 12 cm of reinforced concrete. On the system a 95 cm layer of sand was used to create a load bearing capacity of 600 kN. The retaining wall perimeter wasn’t placed watertight so the drainage mat could accommodate water flow to the surrounding soil. The cellar also has a water flow regulating system to have a controlled effluent to the regular storm water sewer system. By creating a storm water cellar this way the principal has a system that can accommodate large amounts of storm water and an acceptable dissipating rate. The cellar can be accessed via a manhole for inspection and cleaning.






Watershell Atlantis modules and retaining wall Water flow via the spacing of the retainer wall

Pipe lines going into the chamber Inside view of the system

The first infiltration cellar was constructed for a Municipality. This newly developed infiltration system was used in a suburb. The storm water drains from roads and roof tops are collected and directed towards the cellar that has a water bearing capacity of 600 m³ and only takes up 372 m². This results in capacity of 1,620 ltr/m². The system was built using the Watershell Atlantis. This system also has a high load bearing. The perimeter was created using water pervious prefab concrete elements. The floor of the cellar consists of a permeable layer connected to a gravel sub layer. Infiltration is possible via the bottom of the system. The biggest advantages of this type of system are the accessibility via a manhole cover and the possibility of cleaning the system if needed. The internal height of the system is 1.7 m (5.5 feet).






Installing modules Modules, PVC columns and tiles

Overview system Concrete and inspection manholes

This large storm water infiltration system was built to divert storm water from the surrounding buildings and keep the water out of the sewer system. The system consists of the Watershell Atlantis modules stacked on PVC columns to create a large underground cavity and still be cleanable and inspectable. Accessibility of the system is via a manhole. The project was constructed as a joint venture between the contractor and the supplier. The perimeter was built using XPE drainage board material. Another option to build the perimeter is using pre-fabricated concrete forms. This system can withstand traffic loads up to 200 kN.






Positioning of the retainer wall Pouring of the concrete floor (no reinforcement)

Installing the Watershell system Pouring of the concrete cover on the modules

This infiltration cellar was built as a result of a reconstruction of a large above ground parking lot. This project required a storm water infiltration system that could double as a parking lot. This meant that the concrete cover of the cellar must be able to withstand the load of the parked vehicles. The storm water from the parking lot and surrounding buildings is diverted into the cellar and from there it infiltrates into the soil at a controlled rate. Eventually two systems of 150 m³ each were built within a week.



Water Storage Cellar advantages:

• Simple and quick installation process• Accessibility• Inspectable and cleanable• High load bearing capacity• No need for ground backfill• Variable height, length and width• High volume storage capacity• Relatively low costs• Multiple space plan• Great expertise and many reference projects

Just like infiltration fields and cellars, Water Storage Cellars may help to meet a number of requirements and challenges associated with sustainable development, whether building houses, office buildings, industrial areas or infrastructure projects. Water is temporarily buffered and slowly dissipated to either sewer systems or open water. Application possibilities are endless, for example beneath green houses, as sprinkler system water buffer beneath (sports) parks and office buildings.

5 Water Storage Cellar - Summary

Watershelltype

outer Hmm

inner Hmm

Traffic loadkN

D concrete covermm


AtlantisAtlantis

12001200

880850

450�00

120150

0.7980.769

AtlantisAtlantis

16001600

12801250

450�00

120150

1.1821.154

AtlantisAtlantis

20002000

16801650

450�00

120150

1.5671.538

AtlantisAtlantis

2280 (max)2310 (max)

19601960

450�00

120150

1.8371.837

Values are based on 600 mm ground coverage, Ø 8 x 150 x 150 steel mesh reinforcement and sufficient load bearing capacity of the systems floor. Ground coverage of less than 600 mm can influence reinforcement and/ or concrete D values. Please contact your local Watershell system supplier for more information and/ or engineering questions.


• Required storage volume • Ground water level (GWL)• Effluent rate• Inlet amenities• Outlet amenities• Access amenities• Available area• Traffic load• Ground cover/backfill• Allowed earth pressure


Principal: MunicipalityArea: 2,225 m2



5 Water Storage Cellar - Projects

Installing Watershell against the concrete perimeter 2,225 m2 of modules with steel mesh reinforcement

Pouring concrete Sports field on the 630 m3 water detention cellar

During the redevelopment of an old industrial factory the Municipality wanted to build a park. They devised a totally new concept for dealing with storm water by building a large 630 m³ storage cellar under a sports field. By building the cellar under the field the Municipality was able reduce building costs considerably but also solve a storm water issue. The main advantage for the field was that it wouldn’t be affected by soil settlement.


Principal: Rose nurseryArea: 1,350 m2

Water bearing capacity: 1,200 m3


Positioning Watershell modules in concrete culvert Concrete floor under the modules

Watershell system based on arches and columns Pouring of the concrete

A Rose nursery needed a large storm water detention system to collect rain water runoff of their green house. The system had to be able to detain 1,200 m³ of water and the available space was 1,350m². The detention cellar also doubled as the foundation for the green house. Storm water is collected and treated and then reused as irrigation for the plants. Research has proven that underground storage of water results in better water quality, because of the lack of UV light and a constant water temperature. The potential for algae growth is very low.






Concrete floor and walls Building the test site

Top view test site Filling the columns with concrete

This cellar is used as a temporary storm water detention unit. The water is eventually pumped and dispersed. During the build a test site was created to test the filling of the columns with concrete. By using transparent pipes a visual inspection was possible. After hardening the pipes were cut and tested to see how well the pipes were filled and how well compaction was achieved.






Excavation for the water detention system Pouring of the flooring

Installing the hollow walls Installing the modules

A 550 m³ storm water detention cellar was built under a bicycle path. This path will also double as a road for heavy traffic. Storm water from roof tops and the surrounding streets is collected and then pumped at a controlled rate to open water. The cellar doubled as the foundation for the road and bicycle path and has an internal size of 2.5 m x 130 m. (width x length). The walls are based on hollow wall technology which means they have a cavity between the outer and inner shell.






Floor with gutter Installing the Watershell Atlantis modules

Watertight concrete walls Pouring of the concrete cover of the system

In a suburb a Municipality wanted to create a storm water detention system to buffer the peak amount and have it dissipate at a controlled rate. This meant the sewer system would be relieved of the excess water. The natural soil was impervious so infiltration wasn’t a viable option. The stored storm water would then be pumped up and dispersed into the nearby stream at an acceptable rate.



Principal: Home OwnerArea: 55 m2


Load bearing capacity: 4 kN/m2

Material: Watershell 55

Installing modules on concrete floor Installing of the modules

After installation Project’s location

This water detention system was built on a home owner’s premises. As this area has a water deficiency this home owner decided to build a storm water detention system to reuse the storm water to irrigate the garden, flush toilets and wash the car.



Principal: Bus CompanyArea: 140 m2



Installing modules Side view during installation

Close up of the modules against the concrete wall After positioning the system before pouring concrete

Storm water from the roof of one of the large buildings is redirected to the detention cellar. This water is used to wash the busses. A bus washing facility was constructed on top of the detention cellar.



Principal: Akzo Nobel FactoryArea: 460 m2



Installing the modules in the concrete culvert Cellar’s dimensions are 57.5 x 8 m

Finished roof of the system, top view Accessibility to pump unit (capacity 30 m3/hour)

This project is a 700 m³ detention cellar built to accommodate storm water runoff from the surrounding industrial area. The cellar was built under a major road running between buildings. Storm water from roofs and roads are collected and dumped into the cellar using gravitational force. The water is then transported over a distance of 600 meters and pumped into an open body of water. The pump has a capacity of 30 m³/hour. The alternative to the cellar would have been a pond, but that would have meant they needed about 3,200 m² of open space to dig it. The cellar saved space and could be capitalized on because it was still usable space. This proved to be the most economical solution to the question at hand.



Principal: Green house nurseryArea: 550 m2



Floor has been poured Concrete walls are ready

Installing the Watershell Atlantis system System ready for concrete pouring

The farmer chose to build a storm water detention system that can detain runoff water from the roof of the green house and use it to irrigate the plants. By building a cellar they could create the needed water storage without using valuable outside space. A pond or large tank would have been the normal alternative. The water in the cellar is of very high quality and at constant temperature which means no additional energy is needed to keep the water at a desired temperature.






Empty concrete culvert with floor and walls Installing the Atlantis modules

Ready for concrete pouring Pouring concrete

This storm water cellar was build directly beneath the surface and was designed to detain storm water so it could flow into the storm water sewer system at a controlled rate. The system is solely based on gravitational flow. This provided the Municipality with an inexpensive method of storm water management. The system was built under a road and is L-shaped.



6 Root Bridge - Summary

Cracked pavements, uprooted tree grates and turf paving can be hazardous for pedestrians, bikers and traffic. Tree roots need air as well as water, which is why these roots search for cracks in the pavement where rain or condensation form pockets and so cause damage to surrounding infrastructure. The Watershell root bridge application offers the solution to the root growth problems for mature as well as newly planted trees by creating a second grade on top of the roots. An air pocket is constructed beneath the pavement forming this second grade, thus providing roots with enough air and water to survive the harsh conditions of urban areas. A Watershell root bridge prevents uprooting and creates durable smooth surfaces to safely walk and bike on.

Root Bridge Advantages:

• Simple and fast installation• Second grade on top of root system• Air pockets prevent uprooting• High load bearing capacity (>H20)• No ground cover necessary• Variable sizes, L x W x H• Relatively low costs• Great aeration and watering• Finish concrete covers with variable designs• Great expertise and many reference projects


• Aeration• Irrigation / watering• Excavation depth• Available space • Traffic load • Backfill• Allowable earth pressure

Root bridges have no standard solutions. The concrete cover needed is dependant on several variables and should be engineered for every system. On top of the concrete cover a diversity of paving can be used such as tiles, stone, asphalt, concrete printing or a layer of ground backfill. To calculate the amount of reinforcement and concrete cover thickness needed per system please contact your local Watershell system supplier for more information.


6 Root Bridges - Projects


Water bearing capacity: n/aLoad bearing capacity: 450 kNMaterial: Watershell 16

Leveling soil around the tree Watershell system spaced around the tree

Paving consisting of natural stone Chestnut tree after completion of the project

In a Cultural park the Municipality wanted to preserve a heritage chestnut tree. The tree was in the centre of the park and paving was going to be installed all around the tree. To provide the roots the space to grow and still provide the necessary water and air the Municipality chose to use the root bridge system. A water and aeration drain pipe provides the optimal environment for the roots.



Water bearing capacity: n/aLoad bearing capacity: 450 kNMaterial: Watershell 8

A former military base in the center of the city was adapted to create living and working areas. The entrance was a combination of heritage buildings and new construction with two heritage trees flanking the driveway. The trees had to be preserved to maintain the natural landscaping around the base. To prevent root damage to the driveway the Municipality constructed a root bridge system using Watershell. The Watershell modules created a second layer on top of the roots to provide them with the ability to grow without causing damage to the surrounding infrastructure. They used a stone print in the concrete for maintenance free and sustainable paving.

Installing the 8 cm high Watershell modules Concrete paving with stone print

Entrance to the building Sustainable root free driveway




Water bearing capacity: n/aLoad bearing capacity: 450 kNMaterial: Watershell 12 Modules

During a restructuring of a road near a railroad track the Municipality wanted to preserve an old tree. The tree was located to near to the new road and could cause problems in the future. They decided to create a root bridge system to provide the roots the space to grow with sufficient water and air. The system was built using the Watershell 12 modules and a concrete cover.

Spacers and rebar Modules on a foundation of concrete tiles

Watershell used as a road foundation Overview of the project






The Municipality wanted to prevent tree roots from damaging the bicycle path after restructuring. They estimated that the abutting four large trees would cause damage to the cycle path. By constructing a root bridge they were able to prevent damage and thus save on maintenance costs in the future.

Installing the Watershell modules Modules with steel mesh on concrete tiles 50 cm center to center

System overview before pouring concrete Root bridge after completion with a steel guard rail



7 Tree Environment Protection - Summary

Trees in urban areas grow in harsh conditions. The underground and infrastructure conflicts with the root growth and thus with the well being of the trees. The surrounding soil is heavily compacted by traffic and the roots have difficulty reaching water or getting air. With the Watershell system a tree environment can be created that suits its needs. When building the system a layer consisting of concrete is constructed. The soil under this layer will not compact and the roots have the ability to grow without causing damage. The space underneath the concrete cover is filled with soil with sufficient nutrients for the tree. The system itself is constructed as a growth layer and the tree can flourish with no limitations during its life.

Tree Environment Protection Advantages:

• Create a large space for the roots to grow• Less maintenance of infrastructures• Aeration layer prevents upward root growth• Aeration and irrigation of roots• Roots accessible for sampling• Easy and fast construction• Create a second layer on top of the roots• Aeration layer prevents pressure on the roots• High load baring capacity (>H20 loading)• No backfill needed• Variable in size (LxWxH)• For newly planted and old trees• Relatively low construction costs• Great expertise and many reference projects

Watershelltype

Traffic LoadkN

D tilemm

D concretecovermm

H outermm

Soil capacitym3/m2

Watershell 55Watershell 55

450600

8080

120��0

750770

0.4950.495

AtlantisAtlantis

450600

8080

120��0

900900

0.5710.551

AtlantisAtlantis

450600

8080

120��0

11001100

0.7630.744

AtlantisAtlantis

450600

8080

120��0

13001300

0.9550.936

Values are based on Ø 8 x 150 x 150 steel mesh reinforcement and sufficient load bearing capacity of the system’s floor. Please contact your local Watershell system supplier for more information and/ or engineering questions.


• Aeration• Irrigation / watering• Ground water level (G.W.L.)• Available space• Traffic Load• Allowable earth pressure• Soil consistency


7 Tree Environment Protection - Projects


Capacity: 430 ltr of soil per m2


Installing the Modules with the cutouts Using a jig to fill the modules with soil

Tree planting location defined Tree environment protection system with XPE board perimeter

When reconstructing a road in the Municipality they planted hundreds of new trees. The space in which the tree roots can grow is often limited. By using the Watershell system around the tree base and partly under the new road the roots were given sufficient space to grow without causing damage to the road or utilities. This will enhance the tree’s life expectancy. Humus was filled between the Watershell modules and the concrete top layer was poured to cover the system. This method of construction also benefited the road as the shoulder was reinforced through the concrete layer.


Using vacuum excavation to expose the roots Installing PVC columns on a tile foundation and installing drains

Installing the Watershell modules Concrete top layer as foundation for path made from broken shells

Due to the intensity of traffic traveling over the shell path the surrounding soil was compacted to densely for the tree roots. The tree’s growth was seriously in danger. By using the Watershell as a tree environment protection system the life expectancy of the trees has been extended. Some of the trees are over 150 years old. The concrete top layer of the Watershell system is now the load bearing system and compaction of the surrounding soil is no longer an issue. By using vacuum excavation on this project the tree roots weren’t damaged during construction. The perforated concrete layer on top now allows rainwater to get to the roots and the drain pipe placed between the roots before backfilling is an ideal aeration system.




Load bearing capacity: 450 kNMaterial: Watershell 16 Atlantis




Load bearing capacity: 450 kNMaterial: Watershell 16 Atlantis, outer height system 90 cm (35 inches)

Installing PVC columns on a tile foundation Soil under the modules

Formwork for planting the trees Tree planting space after concrete pouring concrete

This reconstruction project is situated in an urban area with sub surface ground and above ground infrastructure. To obtain sufficient sub surface space for the trees to grow the Municipality chose to use the Watershell Atlantis system. The project was constructed in different stages and consisted of 1,350 m2 of the Watershell Atlantis system. This meant they needed 5,400 Watershell modules and 7,200 PVC columns with a height of 74 cm (29 inches). The system contains 750 liters of soil per square meter and within this layer water drains and air drains have been installed to provide the roots with the necessary air and water. On the 12 cm (4.7 inch) concrete top layer the contractor installed a natural stone that can withstand loads up to 450 kN. This system provides the roots the space to grow and the 10 cm (4 inch) space between the concrete top layer and the soil layer functions as a natural root pressure barrier.



Installing PVC columns Backfilling with soil

Watershell Atlantis on the PVC columns Overview of the end result


The first Tree Environment Protection project was completed in 2001. In a large city the system was installed next to a streetcar rail under the streetcar stop. This was done to create a space for the newly planted trees to grow. Every tree had approximately 50 m³ of soil to grow in. The soil has a low load bearing capacity so the Watershell system had to cope with the loads to stop the soil from being compacted. This system has proven to be the right step towards tree care.


Capacity: 1,430 ltr of soil per m2



In a city center five tree environment protection systems were installed. The main arguments to do this were that the soil layer wouldn’t compacted, the cobble stone paving wouldn’t get damaged over time and the costs for installation were relatively low. Root pressure and collapsing and/ or compacting soil are the most damaging factors for cobble stone pavements.

Principal: MunicipalityArea: 172.5 m2



Installing the tile foundation and column base supports

Backfilling the soil, columns are temporarily capped

Installing the Watershell Atlantis modules Formwork around the inspection manhole




The Municipality wanted to create a new city plaza and plant 18 Lime trees. The problem the Municipality had with just planting trees the traditional way was that they expected continued compaction of the soil and that would lead to settlement of the plaza paving. The settlement would cause high maintenance costs. The Watershell system was strong enough to bear the load of traffic in the plaza and create the tree root protection needed. The trees would now have the life expectancy the Municipality was looking for. Each tree had approximately 30 m³ of soil to grow in. The whole project was completed within a two month period.




Installation of the PVC columns on concrete foundation

Modules with formwork around the tree planting area

Pouring concrete on the modules Project overview


New trees are planted in a reconstructed shopping center plaza. To guarantee the life expectancy of the trees the Municipality placed the Watershell system around the planting areas. This plaza has heavy traffic load from trucks bringing supplies to the different stores. These loads would have resulted in compaction of the surrounding soil. The Municipality also wanted an irrigation system within the Watershell modules. The irrigation was installed just underneath the modules on top of the soil. This open space is also ideal for aerating the roots. In total 33 trees are planted using the Watershell Tree Environment Protection System.




Project overview Overview with tree planting spaces

Irrigation system was installed An 11 cm (4.3 inches) space between the soil and the bottom of the Watershell modules



Watershell modules are ideal as a light weight backfill substitute. When renovating or building new homes usually large amounts of backfill are needed to raise floors to desired level. This can also apply when building parking garages or even roof top gardens. The Watershell system offers a fast and easy solution when light weight material is needed, this in turn results in an overall reduction in the total weight of the construction.By using the Watershell system it reduces the amount of rebar and concrete needed but still results in the desired maximum load bearing capacity. See also the table below for weight factors as defined in kg/m² per type of Watershell module .

Light Weight Backfill advantages:

• Reduces overall weight• Rigid structure• Heavy load bearing capacity• Excellent gradient for runoff water• System can be inspected• Possibility of installing utilities inside the system• Fast and easy installation• Variable in size (L x W x H)• Very cost effective• Excellent alternative for EPS structures• Great expertise and many reference projects

Watershelltype

inner Hmm

D concrete covermm

Concreteamount

(ex D) m3/m2

outer Hmm

weightkg/m2

Watershell 55Watershell 55

450450

80100

0.0650.0��

530550

360408

AtlantisAtlantis

750750

80100

0.0550.0��

830850

334382

AtlantisAtlantis

12501250

80100

0.0730.0��

13301350

377382

AtlantisAtlantis

15001500

80100

0.0�20.0�2

15801600

377425

AtlantisAtlantis

17501750

80100

0.0910.0��

18301850

399447

Please contact your local Watershell system supplier for more information and/ or engineering questions.

8 Light Weight Backfill - Summary


• Substructure strength• Runoff specifics• Load bearing capacity of the system• Weight of the system• Gradient in the system• Protection of the substructure• Utility lines• Monitoring


8 Light Weight Backfill - Projects

During renovations on a historical building the Watershell system was used to create a new ground floor. The old sub flooring beams had to be replaced and by using this system a new floor could be constructed on the spot. This hollow space also created a much needed natural ventilation underneath the ground floor. The system was the ideal solution in this case because it is light weight and easy to install. The available work space was very tight which made het difficult to use traditional building methods. The finished structure was light and the concrete layer was pillared every 50 cm square. This means the load of the floor was distributed evenly over a large area. A 800 x 800 mm (32” square) manhole cover was used for accessibility of the system.

Principal: Private SectorArea: 55 m2

Capacity: n/aLoad bearing capacity: 3 kN/m²Material: Watershell Atlantis

Overview without the ground floor in place Leveling sub grade and installing the concrete tiles

Cutting the modules to size View from within the Watershell system after completion


Principal: Private CompanyArea: 650 m2

Capacity: n/aLoad bearing capacity: Axle load 180 kNMaterial: Watershell Atlantis

Installation of L-shaped walls as a perimeter Installation of the Watershell Atlantis system between the walls


Modules’ installation at 50% of completion Modules’ installation at 90% of completion

During renovation of an industrial building the owners wanted loading docks to be installed but the subfloor wasn’t designed to handle heavy loads. The first design specified the use of Styrofoam as a light weight backfill. Watershell was then suggested as an alternative and this turned out to be more economical. This system does have a high load bearing capacity, is light weight and creates a crawl space beneath the loading docks.


When building new silo buildings the owners requested a ventilated floor be installed. By using the Watershell 45 modules not only was the ventilation requirement met but it also created a space for the utility ducts.

Principal: Private CompanyArea: 450 m2

Capacity: n/aLoad bearing capacity: 60 kN/m²Material: Watershell 45

Installation of the Watershell on top of existing utilities Modules cut to size

Utility ducts coming up from below the modules Example of 1 square meter of Watershell 45



A Municipality of a large city was redesigning a plaza. Unilever wanted the plaza to be raised to the same height as their office entrance but the new plaza had to be built on an existing underground parking garage. The roof design of the garage wasn’t strong enough to accommodate heavy loads. The plaza itself was constructed in such a way that the runoff water would be diverted to two sides. By varying the length of the columns for the Watershell Atlantis system the required runoff gradient could be achieved. The Watershell system created the required height without straining the existing garage roof top. The end result is a plaza that can be accessed by light traffic and all necessary utility lines are installed within the system.

Principal: Unilever CompanyArea: 1,200 m2

Capacity: n/aLoad bearing capacity: 2.5 kN/m²Material: Watershell 16 Atlantis Watershell 8 and Watershell 12

Watershell modules installed on a geotextile Modules installed at various heights

Expansion joint were installed required to accommodate natural stone paving

Overview of the end result with sculpture in the background



A home owner wanted a roof top garden. The design specified the location of the patio, lawn and trees but the roof wasn’t designed to bear a heavy load. By using the Watershell modules the weight reduction of almost 30 metric tons was tremendous, saving the owner granular backfill material costs.

Principal: Home ownerArea: 150 m2

Capacity: n/aLoad bearing capacity: 2.5 kN/m²Material: Watershell 16 Watershell 27 and Watershell 40

Installation of the modules on a roof top Filling the modules with granular material

Designated area created for planting trees End results with lawn, patio and trees



In a Municipal swimming pool they wanted to create a safe swimming environment for the children. The existing pool had a major drop from the shallow to the deep and during renovations this was a main issue that had to be addressed. By using the Watershell modules the bottom of the pool was raised to create a regular declining floor. The space under the modules was used for utilities. The PVC columns used for the Watershell Atlantis system were cut to size so the new concrete floor would be level. The concrete cover had to have equal thickness. The modules were shaped to fit the curved sides of the pool. This project demonstrates the flexibility and the diversity with which Watershell can be used. Main advantage for the pool owner was that this proofed to be the most economical way to renovate the pool.

Principal: Municipality poolArea: 500 m2

Capacity: n/aThickness concrete layer: 25 cm (10”)Material: Watershell Atlantis

Existing pool situation Installation of the Watershell system and utilities

Installation overview End result


Documents

Watershell Catalogue Specto Ct August 2009