11/10/2010 1

Steel and Synthetic Fibers in Tunnels and

Mines

Presented by Jeannine Jones, BASFNovember 5, 2009

Steel Fibers by

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Purpose of today’s meeting

To help engineers and designers design with fibers for shotcretingand final linings

To help you quantify the value, from an owners point of view, ofusing fibers instead of traditional reinforcement

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Agenda

Identification of the correct fiber for various applications

How to quantify material and labor savings of fibers vs. traditional reinforcement

Designing with fibers

Fibers in precast, final linings and cast-in-place liners

Fibers in conjunction with admixtures

Fibers which can reduce spalling in fires

Waterproofing membranes combined with fibers vs. waterproofing PVC and rebar

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Why Use Fibers?Generally…

In Short, Fibers Work!

Fibers Reduce Plastic Shrinkage Cracking

Fibers Reduce Plastic Settlement Cracking

Fibers Add Impact and Abrasion Resistance

Fibers Reduce Permeability

Fibers Provide Shatter Resistance

Fibers Impart Toughness & Residual Strength

Fibers are “Built in” Reinforcement!

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Which Fiber to Use?

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Identification of the correct fiber for various applications

Explosive spallingMicro Fibers – these fibers provide voids for steam to move into after they melt @ 320°F (160°C)

Spillways, temporary tunnel linings, anything non-structuralMacro fibers – macros can replace WWF and light gauge rebar, provide durability, are pumpable and perform post first crack reinforcement– Economical way of providing some reinforcement for the temporary tunnel linings where tunnels are designed as

only temporary structures

Shotcrete, final tunnel linings Steel fibers – provide primary, structural reinforcement, and some flexural, shear and tensile stress reinforcement, improve durability, toughness, ductility & are pumpable

Where not to useTunnel Linings– Macro fibers – may have creep issuesPVC Sheet Membranes– Steel Fibers – puncture membrane

Not Every Fiber is the Same

Steel Fibers by

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Identification of the correct polymericfiber for various applications

Micro Fiber – for explosive spallingMonofilament micro fiber typical features:

– High fiber count/yd³/m³ - at least 60MM/lb

– Length between 6 – 13mm

– Diameter < 32µ

Macro Fiber – for secondary, post first crack reinforcementMacro fiber typical features

– Length 1.5” to 2” typically

– Tensile Strength – min of 40ksi (275MPa)

– Modulus of Elasticity – min of 4,000ksi (2,750MPa)

– Average Residual Strength – 150psi @ 3 lb/yd³ (1.8kg/m³)

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Identification of the correct steel fiber for various applications

Aspect ratioAspect Ratio is the length over the diameter of the fiberAspect Ratio gives you an indication of the performance of the fiber. The higher the aspect ratio, the higher the performance with respect to impact resistance, abrasion resistance, toughness, ductility, crack resistance.Typically between 40 – 60

Volume concentrationThe higher the volume, the better the performance, although the shotcrete will become more difficult to mix, convey and shoot atthese higher dosages.

Steel fiber typical features:Length – 1.25 in. (30mm) to 2 in. (50mm)Deformed endsType I meeting ASTM A820 (NB – Type II fibers do not have the same performance qualities as type IDosages between 50 lb/y³ (30 kg/m³) and 135 lb/yd³ (80kg/m³) with most common dosage at 100dlb/ yd³ (60kg/m³)

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How Much Can Be Saved Using Fibers?

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Quantifying material and labor savings of fibers vs. traditional reinforcement

The steel typically pulled out of the tunnels and mines is #5 & #6 rebar, double layeredHard and Soft Dollar Savings

50% of a shift can be spent hanging mesh – this is time lost on excavationFinal Lining Savings – Can save 20-25% of steel cost– Can increase productivity by 30-50%Cast in Place Savings– Can increase productivity by 50% if you pull out all of the

rebar. If you leave some, then it’s ~ 30%Shotcrete Savings– Can increase productivity by 50%Safety issues – reduce tripping, material handling & falls

#5 Rebar

#6 Rebar

The faster you can excavate, faster contractor gets paid and can move on to next job

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Designing with Fibers

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Some background on steel fibers

Why use Steel Fiber Reinforced Concrete (SFRC)?Steel fibers will add crack resistance, ductility, energy absorption and impact resistance

Why are steel fibers a better choice than wire mesh or rebar?They can provide superior residual load carrying capacity at small deformations and equivalent performance at large deformationsYou can do away with installation costs of WWR and rebarReduce hazards for employeesIt can follow the exact contours of the rock face whereas WWR often requires 2 in. (50mm) of cover as well as filling of voids behind the mesh w/ shotcreteYou may see a drastic reduction (up to 40%) in shotcrete material with SFRC in blocky or fractured rock surfacesIf there are voids behind the WWF, then phenomenon like “ice-jacking” can occur more easilyProduction rates/advance rates should be faster with SFRC – up to 50% of labor time can be reduced

What may be the negatives to using SFRC?Slightly higher wear on concrete pumping equipment– More wear on equipment with rubber wearing pads – use tougher wearing pads and carefully control tolerance of

setting of wearing pads– May be greater rate of wear in hoses and nozzles– Avoid sharp bends in hoses

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Beginning the process

When specs are being created, you use the manufacturers information to determine which material to use

For example, if a segment needs to achieve 400 psi at 3mm deflection according to ASTM C1609, a fiber is selected which has the necessary properties and dosage rate.

There is a mandatory procedure in any precast job that you do a test using the mix design, aggregate and fibers which will be used to make sure that performance requirements are met.

A QC person will then perform testing for a pre-determined number of segments or distance to make sure everything is still in spec.

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Mechanical properties and test methodsSelect the appropriate test below to help you decide which design code to use

American Codes:ASTM C1609-07 Standard Test Method for Flexural Toughness and First-Crack Strength of Fiber-Reinforced Concrete (Using Beam With Third-Point Loading)

ASTM C1399-07 Test Method for Obtaining Average Residual-Strength of Fiber-Reinforced Concrete

European Codes:UNI 11039 Steel Fiber Reinforced ConcreteEFNARCEN-14488 Testing Sprayed Concrete: Flexural StrengthsRILEM

Japanese Code:JCI-SF-4 Method of Test for Flexural Strength and Flexural Toughness offiber reinforced concrete

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Relevant design codes, guidelines and reports in FRC worldwide:

Rilem TC162 “Test and design methods for steel fiber reinforced concrete” (England)

TR 63 Steel fiber reinforced concrete (England)

“DESIGN , PRODUCTION AND CONTROL OF STEEL FIBER REINFORCED STRUCTURAL ELEMENTS” Standard UNI U73041440 (Italy)

CNR_DT204_2006 – Guidelines for design and construction of Fiber reinforced concrete structures (Italy)

ACI 318-08, Chapter 11. Shear Reinforcement (USA)

ACI 544-3R-08 Guide for Specifying, Proportioning and Production of Fiber-Reinforced Concrete

FRC design guidelines worldwideWhich design code should be used?

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•Material testing definition for FRC (compression stress, first crack moment, tensile strength, toughness index , residual strength)

•Constitutive bilinear law definition through flexural residual strength testing. NLFM (non linear fracture mechanics)

Basic guidelines to develop a design with 100% SFRC or a hybrid solution(SFRC + rebar reinforcement)

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SFRC Material Constitutive Laws σ-w

From the experimental flexural test ASTM C1609/UNI 11039

σ n

CTODm

Ec

σ

ε

fct

Pre-peak, σ-ε Post-peak, σ-w

σ

w1 wc

w

fct

s1

+

The numerical inverse analyses were provided by using NLFE software

From experimental tests

Inverse analyses

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Numerical and experimental

R60 - FF1 - 35 kg/m3 - Vf=0,45%

0

1

2

3

4

5

6

0.0 0.1 0.2 0.3 0.4 0.5CTODm [mm]

Nom

inal

Str

ess

sN [M

Pa]

Experimental

Numerical

R60 - FF1 - 45 kg/m3 - Vf=0,57%

0

1

2

3

4

5

6

7

8

9

0.0 0.1 0.2 0.3 0.4 0.5

CTODm [mm]

Nom

inal

Str

ess

sN [M

Pa]

Experimental

Numerical

R60 - FF3 - 25 kg/m3- Vf=0,32%-6

-5

-4

-3

-2

-1

00.0 0.1 0.2 0.3 0.4 0.5

CTODm [mm]

Nom

inal

Str

ess

sN [M

Pa]

ExperimentalNumerical

R60 - FF3 - 35 kg/m3- Vf=0,45%

0

1

2

3

4

5

6

0.0 0.1 0.2 0.3 0.4 0.5

CTODm [mm]

Nom

inal

Str

ess

sN [M

Pa]

Experimental

Numerical

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0

1

2

3

4

5

0 1 2 3 4 5 6

Crack opening [mm]

Nom

inal

str

ess

[MPa

]

Vf = 0,00%Vf = 0,45%Vf = 0,57%

0

1

2

3

4

5

0 1 2 3 4 5

Crack opening [mm]

Nom

inal

str

ess

[MPa

]

Vf = 0,00%Vf = 0,32%Vf = 0,45%

MasterFiber™ FF1 MasterFiber™ FF3

Constitutive Laws σ-w

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Flexural test performace

FF1

FF3

FS1

FS3N

FS4N

FS7

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Precast Segment Lining Design Examples

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Precast TunnelTunnel Lining Cross-Section

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Tunnel ground condition evaluation ofbending moment and axial force diagram

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Precast tunnel segment geometries

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One Ring:7 + 1 segments

Wood Blocks

Storage load condition

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Load condition – TBM load action

Escavationdirection

Hydraulicjacks

Shield

Boring head

Segment’s ring

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Rebar only

Reinforcement comparison

SFRC + Rebar

We suggest a combined reinforcement made of 35 kg/m3 of MasterFiber FF3 and steel rebar as shown in the following picture

350 350

350

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Tunnel segmentsDisplacement under service load

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Tunnel segmentsLongitudinal stress under service load

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Tunnel Segments: Non Linear Analyses, Comparison

0

5000

10000

15000

20000

25000

30000

0 1 2 3 4 5 6Displacement [mm]

Load

[kN

]

45FF1 Plain

RC RC35FF1

RCO35FF1

Quite the same loadcapacity

Optimized reinforcement

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Segment coming out of mold with suction process

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Segment being placed on a carousel system

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Crane picking up three segments

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Segments in storage

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Line 9 Subway Barcelona, Spain

•Tunnel diameter: 12 m•6 segments + 1 key•Concrete 50 MPa•Hybrid design :

•Rebar 30 kg/m3 + SFRC 30 kg/m3

•MasterFiber FF3 Steel Fiber

Steel Fibers by

Case history- precast segments

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Madrid Subway, Spain

•Tunnel diameter: 10 m•6 segments + 1 key•Concrete 50 MPa•Hybrid design :

•Rebar 60 kg/m3 + SFRC 25 kg/m3

•MasterFiber FF3 Steel Fiber

Steel Fibers by

Case history- precast segments

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Genoa Subway, Italy

•Tunnel diameter: 6.2 m•6 segments + 1 key•Concrete 40 MPa•Hybrid design :•Rebar 60 kg/m3 + SFRC 25 kg/m3

•MasterFiber FF3 Steel Fiber

Steel Fibers by

Case history- precast segments

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Orakei Main Sewer HobsonDivision in New Zealand

•Tunnel diameter: 3.7 m•6 segments + 1 key•Concrete 50 MPa•100% SFRC Design :•40 kg/m3

•MasterFiber FF3 Steel Fiber

Steel Fibers by

Case history- precast segments

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Bright Water Sewer System Seattle Tacoma, WA USA

•Tunnel diameter: 3.7 m to 5 m•5 segments + 1 key•Concrete 50 MPa•100% SFRC Design :•40 kg/m3

•MasterFiber FF3 Steel Fiber

Steel Fibers by

Case history- precast segments

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SFRC precast segment lining Design Guideline

250-400 (10-16)35-50 (60-85)250-400 (10-16)20-30 (34-50)MasterFiber FF3

250-400 (10-16)40-60 (67-100)250-400 (10-16)25-35 (44-60)MasterFiber FF1

Thickness mm (in.)

Dosage kg/m3

(lb/yd3)Thickness mm (in.)

Dosage kg/m3

(lb/yd3)

SFRCMix RR + SFRC

Fiber Type

Usual dosage and thickness by application

Tunnel Final Lining

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Shotcrete Lining Design Examples

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Materials:Fiber reinforced concrete:•Compression: 35 MPa•Tension resistance at peak load= 4 MPa•Tension in 0.6 mm of crack opening =3.5 MPa•Tension in 1.5 mm of crack opening= 2 MPa

Rock around the tunnel:Elastic Modulus: 2000 MPaUnit Weight= 2.2 Ton/m3

Load Case:Internal radial pressure from inside to the rock:200 kPa300 kPa500 kPaThe drawing units are in meters.

Shotcrete lining tunnel example

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Cracking shotcrete tunnel lining

The load is increased from 100 – 500 kPa

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The load is increased from 100 – 500 kPa

Cracking process in detail

Cracking shotcrete tunnel lining

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Shotcrete Round Panel test ASTM C1550

Loading piston Specimen

LVDT yoke anchored at transfer plates

LVDT

The required dimensions of the panel are 75 mm (3 in.) inthickness and 800 mm (31.5 in.) in diameter

ASTM C 1550-02:Standard Test Method forFlexural Toughness of FRC andShotcrete (Using Centrally LoadedRound Determinate Panel)

0 10 20 30 40 50

Displacement (mm)

0

10

20

30

40

Load

(kN

)

Integrate the area under the curvebetween the (corrected) origin andthe specified total deflection

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Shotcrete Guideline - based on energy absorption test for excavation rock stability

ReferenceTR-63

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•Shotcrete Final Lining PINALITO (Dominican Republic)

•Hydroelectric System

•Dosage rate: 40 kg/m3 (67 lb/yd3) MasterFiber FS3N

Steel Fibers by

Case history- shotcrete final lining

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SFRC shotcrete lining Energy absorption guideline

35 (60)30 (50)25 (44)MasterFiber FS7

35 (75)40 (67)35 (60)MasterFiber FS3N

Dosage kg/m3

(lb/yd3)Dosage kg/m3

(lb/yd3)Dosage kg/m3

(lb/yd3)

ASTM C1550 = 450 J

ASTM C1550 = 350 J

ASTM C1550 = 225 J

Fiber Type

Usual dosage and typical lining thickness by Energy Absorption Test

Tunneling Shotcrete

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Final Lining Designs Examples

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SFRC cast in place final lining Design guideline

Replacing double layer rebar #5

ARC 100% SFRC

67 lb/yd3 SFRC

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SFRC cast in place final lining Design guideline

Reducing rebar size from #8 to #7

ARC 100% SFRC

50 lb/yd3 SFRC

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SFRC cast in place final lining Design guideline

Tunnel Final Lining

250-400

(10-16)

35-50

(60-85)

250-400

(10-16)

20-30

(34-50)

MasterFiber FF3

250-400

(10-16)

40-60

(67-100)

250-400

(10-16)

25-35

(44-60)

MasterFiber FF1

Thickness mm (in.)

Dosage kg/m3

(lb/yd3)Thickness mm (in.)

Dosage kg/m3

(lb/yd3)

SFRCMix RR + SFRCFiber Type

Usual dosage and thickness by application

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•SFRC Final Lining. Highway A3 Salerno –RegioCalabria Italy

•Dosage rate:35 kg/m3 (60 lb/yd3)

•MasterFiber FF1

Steel Fibers by

Case history- final lining

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•SFRC Final Lining

•Highway SS203 AgordinaCencenighe BL Italy

•Dosage rate: 35 kg/m3 (60 lb/yd3)

•MasterFiber FF1

Steel Fibers by

Case history- final lining

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•SFRC Final Lining

•Highway SS203 AgordinaCencenighe BL Italy

•Dosage rate:30 kg/m3 (50 lb/yd3)

•MasterFiber FF1

Steel Fibers by

Case history- final lining

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Using Macro Polymeric Fibers

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Macro polymeric fibers

Uses and Applications:

Synthetic fibers used more in mines than in tunnels

Predominately wet shotcrete, very rarely in dry shotcrete

Used more in initial support shotcrete

Typical Dosages:

Mining – 8-12 lb/yd3, some as much as 14 lb/yd3

Shotcrete initial support – 8-12 lb/yd3

Limits – 18 lb/yd3 difficult for matrix to support anymore due to high volume

Approximate equivalents – 12 lb/yd3 can perform similar to 60 lb/yd3 of steel

Tests:

1550 panel test – synthetics will typically outperform steel

1609 beam test – steel typically outperforms synthetics

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Examples of polymeric fibers in temporary tunnels

Devil’s Slide - Highway Tunnel

Engineers Est.: $240,000,000

Shotcrete for Initial Support

48mm Macro Polymeric Fiber

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Fibers and Admixtures

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Fibers in conjunction with admixtures

Shotcrete – Dry-MixNo changes to mix design, but be aware that if you cut back too much on cementitious content, there may be more total rebound and specifically, fiber rebound.Synthetic fibers in a dry mix are more difficult to deal with due to high level of rebound. It is not recommended to use micro fibers as they can very easily get blown out of the mixSteel fibers provide the most consistent quality in a dry mix

Shotcrete – Wet-MixUse water reducers @ ~8oz/cwt (.5l/100kg) and superplasticizers for silica fume concrete @ ~16-24oz/cwt (1-1.5l/100kg)Wet mixes are more conducive to any fiber’s use

NotesDosages of high/mid range will increase with higher fiber dosages Slump may decrease at higher fiber dosages by 1-2 in.Although slump may decrease workability will not – avoid temptation to re-temper mix which can result in segregation and balling of the fibers and a final product which has lost hardness quality. Just put some energy on the mix and it will move.

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Concrete Fire Spalling

Source: Applications of Micro-Synthetic Fibers for Resistance to Explosive Spalling in Fires. Trevor Atkinson & Peter C. Tatnall

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Types of concrete fire spalling

Surface spalling

If temperature rise is relatively slow, concrete moisture migrates from the heat exposed side and thus pressure build up is minimal, resulting in less spalling

Corner break-off spalling

Also called “sloughing off”

Occurs at corners and edges during later stages in the fire whenconcrete has cracked and weakened

Explosive Spalling is our Focus for Today’s Presentation

Explosive spalling

Occurs with rapid heat rise within the first 10-20 minutes (usually hydrocarbon based) and is by far the most dangerous and damaging form of spalling.

Moisture in the concrete is heated faster than it can move away from the heat, moisture changes to vapor and the vapor increases pore pressure.

Once the pressure exceeds the tensile capacity of the concrete, concrete is violently and explosively dislodged from the concrete exposing more concrete to the fire

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How do polypropylene fibers help reduce spalling?

The most common theory is that because the high fiber count fibers melt at 320 °F (160 °C) this allows the steam from the moisture in the concrete an escape void rather than allowing pressure to build causing explosions.

In addition to this, another more comprehensive theory is that because the polypropylene, when heated, expands 8.5x more than the concrete, they turn crystalline and cause micro cracking in the matrix. The micro cracks join and provide channels for the release of steam.

Typical specs

Fibers with diameters less than 32µ

Lengths between 6mm – 13mm

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Selecting the right polypropylene fiber

Typical specsFibers with diameters less than 32µ

Lengths between 6mm – 13mm

At least 60MM fibers/lb

Recommended dosages 1.7 lb/yd³ (1 kg/m³) – 3.4 lb/yd³ (2 kg/m³)

Some Things To AvoidShorter (6mm), smaller diameter (18µ) fibers may tend to ball and may greatly increase air content (6-8%)

Macro polypropylene and steel fibers have shown no resistance tospalling (due mostly to their lower fiber count/yd³/m³ vs. the PP fibers)

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Time-temperature curve test methods

Most Severe – Hydrocarbon Fuelled FireRWS (Rijkswaterstaat) Curve – furnace temperatures rise rates increase at a rate of 400 °F (200 °C) per minute to 2000 °F (1100 °C) in 5 minutes, with final temperature reaching 2460 °F (1350 °C) and then held there for 2 hours

Another Hydrocarbon Fuelled Fire MethodEurocode I Hydrocarbon – final temperature ~1100 °C and held for 160 minutes

Test for Slower Temperature Rise FiresISO 834 Cellulose – final temperature ~1100 °C and held for 160 minutes but slope of rise more gradual

BASF Will Design It’s M100 UL Test After the RWS Method

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Tunnels using polypropylene fibers to mitigate explosive spalling

Channel Tunnel Rail Link – UK

Dublin Port Tunnel – Ireland

Gotthard Base Tunnel – Switzerland

T5 Heathrow Express Tunnel – UK

Weehawken Tunnel – USA

Paramatta/Chatswood Tunnel – Australia

Vomp-Terfens Tunnel - Austria

Polypropylene Fibers Cost ~1% of Constructed Concrete Lining

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An example of cost from tunnel fire

Mont Blanc Tunnel Fire in 199939 people died

7.4 miles of tunnel between France and Italy were closed for 3 years

Repair costs totaled $273MM (USD)

Italian government lost >$2B in trade

Addition of correct PP fiber is an inexpensive means of protecting lives, reducing catastrophic collapse, repair costs

and commercial disruption

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Waterproofing

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Waterproofing membranes combined with fibers vs. waterproofing PVC and rebar

The most common types of membranes are PVC membrane with heat welded seamsThe most common problems with them are that they are:

Difficult to shotcrete unless there’s strong reinforcement against the PVCProne to leaks behind the PVCVulnerable to “chasing leaks”It is often not recommended to shotcrete steel fibers onto them because of risk of punctures

Solution – Masterseal® 345It’s a fully bonded system – if there’s a leak visible, that’s where the leak isThe main property of the membrane is that it bonds to both the substrate and the concrete which is applied to it creating an impermeable interface – this is what keeps the leak from migrating.No special equipment is needed to apply Masterseal 345 – just use a standard dry gunnite machineThickness of membrane should be a minimum of 2mm and optimum of 3mm. Do not exceed 5mm in thickness since this can cause slow curing.Substrate preparation – It’s essential to have a smooth substrate with limited roughness in order to achieve a continuous membrane. Use a sprayed concrete w/ maximum grain size of 4mmCuring starts immediately after application and once started, it’s irreversible.

Possible Difficulties – Seepages penetrating through membrane in areas where continuous membrane was not achieved. If these occur, they’ll happen within the first day after application. To remediate, inject locally where water seepage is visible.

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MASTERSEAL® 345

FeaturesDry-process material, ready-for-useElasticity 80-140% b/w -4 & 68 ºF (-20 & 20 ºC)Fast curingNo toxic componentsEnvironmentally friendly

BenefitsEasily applied by spraying with uncomplicated equipmentTwo-sided bond with sprayed-concrete allows for monolithic behavior

Chemistry - Vinylacetate-ethylene copolymer and Cement

FAQsWhat thickness is required for the overspraying of concrete?– Minimum 50 mm concrete thickness with fibers. Smaller thicknesses require special efforts to avoid shrinkage

cracks.How are leaking spots repaired? – Puncture repair injection (acrylic) and application with trowelWhat can happen if you spray with too much / too little water?– Too much water (>50 % water): sagging of the freshly sprayed membrane on the wall, longer curing time, risk of

cracking of membrane by very high ventilation with dry air.– Too little water (<25 %): brittle and discontinous (no membrane!). Excessive dust during application.What capacity during application is realistic to calculate?– 70 – 120 m m2/ hour, depending on experience of crew and layout of working sequence.

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MASTERSEAL 345 – BMI test resultsPRACTICAL EFFECTIVENESS OF CEMENT-BONDED SEALING LAYERS FOR SINGLE-SHELL TUNNEL CONSTRUCTION PROJECTS

External tests results and certifications

•EMPA Switzerland: long term pressure test•Mott Mc Donald: Technical report with summary of actual test results•BMI (Innsbruck): Practical feasibility test

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Example of Masterseal 345 with fibersWATERPROOFING OF A SUBSEA TUNNEL WITH A UNIQUE SPRAYABLE MEMBRANE - THE NORDÖY ROAD TUNNEL, FAROE ISLANDS

About the tunnel - The Nordöy road tunnel passes below the fiord between the two islands of Eysturöy and Bordöy in the Faroe Islands. The total length of the tunnel is 6,155 m with a cross section of 64 m²(two lanes). The maximum depth under the sea is 150 m with a minimum rock cover of approximately 40 m. The rock types in the area are extrusive basalts.Goal - Waterproofing of the tunnel contour to avoid the dripping of water onto the actual road surface.Cost - The total cost of the waterproofing of the tunnel made up approximately 10% of the total project cost.Trend - In the last few years there has been a trend to avoid flammablematerials in underground construction. The flammable PE foam sheets were therefore not in accordance with a modern design philosophy with non-flammable materials. The goal was to reduce the amount of the PEfoam waterproofing by more than 50%.Solution - A sprayable waterproofing membrane in a composite liner based on sprayed concrete. Steel fiber reinforced concrete applied after membrane had achieved sufficient curing (10-14 days)Advantages - possibility to locally waterproof smaller areas without the need to bring the waterproofing all the way down to the invert, no inflammable materials, reduced total lining thickness and significant financial benefits to owner and contractor over a technical solution with PVC sheet membrane and cast-in-place concrete lining.

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Thank you for your time!For follow up questions, please call Jeannine Jones at 216-839-7227 or Ashish Goel at 216-839-7055 or find your BASF Sales Representative by Area below:

Haydn Whittam - coal mining only (US and Canada), 606-331-1212

Wes Morrison - Eastern/Central Division, 571-344-3286

Lauro Lacerda - Western Division, 801-726-6488

Mark Mudlin - Mountain Area (primarily Nevada), 775-397-0188

Keith McDonald - Western Canada, 306-222-2270

Floyd Wudrick - Western Canada, 306-221-7919

Brad Knight - Eastern Canada, 705-499-8448

Bill Brosko - Eastern Canada, 705-507-1130

Visit us on the web at www.masterbuilders.com