Waterproofing of Underground Waterproofing of Underground Structures using Spray Applied Structures using Spray Applied MembranesMembranes

Utilisation of Underground Space in Urban AreasUtilisation of Underground Space in Urban Areas Sharm El SheikhSharm El SheikhEgyptEgypt

Ian W NorthcroftIan W NorthcroftRegional Manager Underground ConstructionRegional Manager Underground ConstructionBASF Construction Chemicals UAE LLCBASF Construction Chemicals UAE LLC

Conventional PVC sheet membrane

Water will find path to inner surface of tunnel

Water migrates through sprayed concrete joint

Water migrates to an unlimited extent through geotextile fleece behind sheet membrane (to drainage pipe)

Water may pass through possible flaw in sheet membrane and migrate an unlimited extent behind inner concrete lining

Sprayed concrete

Geotextile fleece Sheet membraneInner concrete lining

Conventional Waterproofing SystemWhen problems occur . . .

Other issues with PVC membranes

They are point fixed, so sprayed inner linings will not be in full contact with first shell, and sprayed concrete quality will probably be poor

They do not bond to concrete on both sides making then unsuitable for economic single shell linings

Because there is no bond, when the PVC membrane leaks . . . It leaks badly over a long length of tunnel!

Relatively slow to install Scaffolding will restrict tunnel access

during installation Specialist applicators needed Complex tunnel geometries cause major

problems for fixing and welding. A real potential for leaks

Masterseal Spray applied membranes - key message

What is Masterseal 345?

MASTERSEAL® 345 is a sprayable membrane for the waterproofing of concrete structures. MASTERSEAL® 345 is “spray applied” in a sandwich construction between layers of sprayed or cast concrete.

Double shell lining with PVC membranes

1st layer of temporary sprayed concrete

Layer of geotextile fleece

PVC double welded membrane

Permanent cast in-situ lining

Fire protection (eg Fireshield 1350)

1st layer of permanent sprayed concrete lining

Layer of spray applied membrane

2nd layer of permanent sprayed or cast concrete lining

Spray applied waterproofing membraneThe membrane forms an impermeable layer which bonds to the substrate, thus creating a continuous structure

RockSprayed concrete

Masterseal DR1

Masterseal 345Sprayed concrete

System layout:

Spray applied waterproofing membrane

Rock support, sprayed concrete: aggregate size 0-4 mm for optimum material consumption

Masterseal 345, 3 mm

Sprayed concrete: 5-10 cm

MEYCO PiccolaDry spray equipment used

Hand Spraying

Hand Spraying Video

Robotic Spraying Video

• Wet-mix process

• Alkali-free accelerators

• Low w/c using hyperplasticisers

• Microsilica technology

• Fibre reinforcement

• Masterseal spray applied Masterseal spray applied membranemembrane

New technologies

1st layer permanent sprayed concrete (fibre reinforced)

Masterseal 345 spray applied waterproof membranes

2nd layer permanent sprayed or in-situ cast concrete

Permanent design thicknessSingle shell liningsSingle shell linings

The development of single shell linings

Temporary design thickness

Temporary sprayed concrete (steel mesh reinforced)Geotextile fleece

Permanent design thickness

Double shell liningsDouble shell linings

Permanent in-situ cast concrete

Plastic sheet membrane (double welded joints)

Masterseal 345 Spray applied membranes - Tunnel applications

Open face constructionOpen face construction

1st layer sprayed concreteMasterseal 3452nd layer sprayed or cast concrete

Hard rock TBM constructionHard rock TBM construction

1st layer sprayed concreteMasterseal 3452nd layer sprayed or cast concrete

Masterseal 345 Spray applied membranes - Tunnel applications

Soft ground TBM constructionSoft ground TBM construction

1st layer pre-cast concrete segmentsMasterseal 3452nd layer sprayed or cast concrete

Spray Applied Membranes are ideal for Complex Geometries, metro stations and shafts

Well suited to drill and blast tunnels

Other versatile & economic options . . .

GW

GW

GW

GW

GW

Systematic or targeted installation of strips of geotextile fleece

Groundwater captured at regular intervals so as not to induce hydrostatic load

1st layer permanent sprayed concrete

2nd layer permanent sprayed concrete

Managed drainage system

Spray applied membrane applied directly to the sprayed concrete substrate.

ReferencesSwitzerland- Giswil Escape Tunnel

ReferencesSwitzerland- Lausanne Metro

Composite sandwich lining using fibre shotcrete-MS 345-Shotcrete with smooth final lining

Applied only where waterproofing was needed, not over entire tunnel length

No water leaks

BrazilMachadinho Hydroelectric Power Station

A significant time saving was achieved compared to the standard approach of PVC sheet membranes

Masterseal spray applied membrane demonstrated its benefits in covering steel inclusions such as rock anchor heads

Masterseal spray applied membrane represented an overall economical saving to the project

ChileRoad Tunnels

SwitzerlandHighway Tunnels

High capacity application of Masterseal spray applied membrane with MEYCO robotic manipulator arm

Geo textile fleece used in isolated wet areas

Construction Chemicals

UGC Europe regionWorkshop Greece 7-8 April 2003

Hong KongTBM Cross passages

The benefits of Masterseal spray applied membrane for complex geometries was evident with its use in the cross passages of a TBM driven tunnel in Hong Kong

Application of Masterseal 345 in the Nordöy tunnel, October 2005

Faroe IslandsNordöy Sub-sea Road Tunnel

Faroe IslandsNordöy Subsea Road Tunnel

Summary Key benefits of spray applied membranes

Reduced lining costs by allowing monolithic behaviour of sprayed concrete linings - single shell linings

High bond strength prevents development of water paths either side of membrane Application flexibility - complex geometries, steel components such as rock bolts

and anchors etc Speed of application especially using Meyco Logica Robotic equipment -

simple process requiring limited work force Does not interfere with other tunnel processes Non toxic, biologically harmless Non combustible All equipment can be cleaned with water Overall a technically superior and more economical system