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MSE Walls & Geosynthetics - Design Basics Webinar April 2016

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Randy McDonald, P.Eng. Director of Engineering Armtec Drainage Solutions Frank Klita Sales Representative Armtec Drainage Solutions Michael McQuaid P.Eng. Design Engineer Armtec Drainage Solutions Andrew Lister Sales Manager Mirafi ® Geosynthetics, TenCate Geotube ® FRIDAY APRIL 22, 2016 / 9AM PST / 11AM CST / 12PM EST TECHNICAL WEBINAR MSE WALLS AND GEOSYNTHETICS DESIGN BASICS
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Page 1: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

Randy McDonald, P.Eng.Director of Engineering

ArmtecDrainage Solutions

Frank KlitaSales Representative

ArmtecDrainage Solutions

Michael McQuaid P.Eng.Design Engineer

ArmtecDrainage Solutions

Andrew ListerSales Manager

Mirafi® Geosynthetics,TenCate Geotube®

FRIDAY APRIL 22, 2016 / 9AM PST / 11AM CST / 12PM EST

TECHNICAL WEBINAR

MSE WALLS AND GEOSYNTHETICSDESIGN BASICS

Page 2: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

YOUR HOST

Janine YetkeDirector of Marketing Armtec, Drainage Solutions

LinkedIn: ca.linkedin.com/in/janineyetke/enEmail: [email protected]

Page 3: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

CPD CREDIT CERTIFICATES

• Qualifies in Most Jurisdictions in Canada & USA for 1 Hour Technical Informal

• Formal completion certificates are emailed within two weeks of attending• Check your local guidelines if unsure of your requirements

Email your complete attendee list should there be multiple individuals viewing the same screen:

• Full Name• Title• Email

[email protected]

Armtec will send certificate to all participants

Page 4: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

Armtec is one of Canada’s largest infrastructure company supplying precast, corrugated steel and HDPE products and solutions. Every day, our proven products, engineered solutions and dedicated people are counted on to support construction and infrastructure projects in communities everywhere. With a national presence and a local focus on exceptional customer service, we are dedicated to building excellence.

Actual 2016

Locations 40

Drainage Locations

Precast Locations

ABOUT ARMTEC

Page 5: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SECTORS

Armtec specializes in all infrastructure markets and segments and can help with any project to ensure you have the right products for the job. Our people have extensive experience and access to resources all across the country, and can help with all facets of product selection, installation and support.

Stormwater Solutions

Mining & Energy

Commercial & Retail Constructions

Transportation Underground & UtilityInfrastructure

Sports & Entertainment

Institutional Construction Industrial Construction Agriculture

Commercial & Residential Landscaping

Forestry Residential & Hospitality

ABOUT ARMTEC

Page 6: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

Armtec Drainage Solutions’ centralized engineering department consists of design engineers, a drafting team, and estimators.

Additionally, professionally licensed Region engineers are located in all Market Areas across the country.

DRAINAGE ENGINEERING SUPPORT & ROLESABOUT ARMTEC

Page 7: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

YOUR SPEAKERS

Michael McQuaid P.Eng.Design EngineerArmtec, Drainage [email protected]

Andrew ListerSales ManagerMirafi® Geosynthetics, TenCate Geotube®

Page 8: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

AGENDA

1. Review of Geosynthetics

2. Types of Geosynthetics

3. Geogrids

4. MSE Wall Components

5. Analysis of MSE Walls

6. MSE Wall Types & Facing Options

Page 9: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

REVIEW OF GEOSYNTHETICS

GEOSYNTHETICS:

GENERIC TERM FOR ALL SYNTHETIC MATERIALS USED IN GEOTECHNICAL ENGINEERING APPLICATIONS, INCLUDING• TEXTILES• GRIDS• NETS• MEMBRANES• COMPOSITES

Page 10: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

POLYMERS USED IN GEOSYNTHETICS

POLYPROPYLENE (PP)TOUGH, FLEXIBLE SYNTHETIC THERMOPLASTIC MATERIAL MADE BY

POLYMERIZING PROPYLENE

• SIMILAR TO POLYETHYLENES, BUT HARDER AND TOUGHER

• PROVIDES GOOD TENSILE STRENGTH RELATIVE TO ITS WEIGHT

• TRANSLUCENT IN ITS NATURAL STATE, PP REQUIRES ADDITIVES TO CREATE UV STABILITY.

• SPECIFIC GRAVITY OF 0.96 (FLOATS); DURABLE, INERT

• MAJORITY OF NONWOVENS AND WOVENS MANUFACTURED FROM PP

Page 11: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

POLYMERS USED IN GEOSYNTHETICS

POLYESTER (PET)

LONG-CHAIN POLYMERS CHEMICALLY COMPOSED OF AT LEAST 85% BY WEIGHT OF AN ESTER AND A DIHYDRIC ALCOHOL AND A TEREPHTHALIC ACID

• FABRICS AND FIBERS ARE EXTREMELY STRONG – HIGH TENSILE AT LOW STRAINS

• VERY DURABLE: RESISTANT TO MOST CHEMICALS, STRETCHING AND SHRINKING, AND ABRASION RESISTANT

• HYDROPHOBIC (REPELS WATER) IN NATURE AND QUICK DRYING

• POLYESTER USED TO CREATE HIGH STRENGTH TO WEIGHT PRODUCTS E.G., GRIDS

Page 12: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

GEOSYNTHETICS

• NONWOVEN - TEXTILE STRUCTURE PRODUCED BY MECHANICAL, CHEMICAL, THERMAL, OR SOLVENT BONDING AND/OR INTERLOCKING OF FIBERS

• WOVEN - TEXTILE STRUCTURE PRODUCED BY INTERLACING TWO OR MORE YARNS, FIBERS, OR FILAMENTS

• KNIT - TEXTILE STRUCTURE PRODUCED BY INTER-LOOPING ENDS OF YARN

• GEOGRID - A GRID LIKE POLYMERIC MATERIAL FORMED BY INTERSECTING RIBS JOINED AT THE JUNCTIONS USED FOR REINFORCEMENT

Page 13: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

FUNCTIONS OF GEOSYNTHETICS

• Separation

• Confinement

• Reinforcement

• Filtration

• Drainage

Page 14: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

Geosynthetics and MSE Walls – Design BasicsTYPES OF GEOSYNTHETICS

Page 15: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

GEOTEXTILES

• ANY PERMEABLE TEXTILE USED IN ANY

GEOTECHNICAL ENGINEERED SYSTEM • ALSO REFERRED TO AS

• Filter Fabric• Filter Cloth• Filter Paper• Construction Paper

Page 16: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

NON WOVENS

• ADVANTAGES• High Flow Rate• Fine Filtration• High Elongation• Flexible• Can Provide Cushion/Protection

• DISADVANTAGES• Low Strength to Weight Ratio

Page 17: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

WOVENS

• ADVANTAGES– High Strength to Weight Ratio– Controlled Filtration– Controlled Flow Rate– Durable– Low Elongation with High Tensile Strength– Installation Resistant

• DISADVANTAGES– Can have poor Flow and Filtration

Page 18: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

WOVENS

Woven Monofilament polypropylene geotextiles• Filtration• Drainage

Woven slit tape polypropylene geotextiles• Separation

Page 19: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

WOVENS

High Performance woven polypropylene geotextiles• Subgrade Stabilization• Reinforcement

High Performance woven polyester geotextiles• Reinforcement

Page 20: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

GEOGRID

WOVEN / COATED POLYESTER - UNI-AXIALEXTRUDED / PUNCHED DRAWN PP – BI-AXIAL

• ADVANTAGES• High Strength to Weight• High Soil Interaction• Protected Yarns - UNI• High Connection Strength - UNI• Bi-Axial or Uni-Axial Strength

• DISADVANTAGES• No Separation

Page 21: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

WHAT’S BEHIND YOUR WALL?

Page 22: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

Geosynthetics and MSE Walls – Design BasicsGEOGRIDS

Page 23: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

TYPICAL CHARACTERISTICS OF PET GEOGRIDS

• High strength uniaxial polyester geogrid

• Strongest geogrid reinforcement available

• Woven and coated with a PVC coating• Vast LTDS tensile strength range

• 18.5kN/m – 253kN/m• Excellent durability properties• 3.6 meter (12 feet) wide rolls• 1.8 meter (6 feet) wide rolls• 1.2 meter (4 feet)wide rolls

Page 24: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

PET GEOGRIDS

• Flexible and Tough• Delivers immediate soil geogrid stress transfer

• High Long Term Design Strengths• Long term design strengths are backed up by more than 100,000

hours of creep testing performed at an outside, independent test laboratory

• Easy Handling• No sharp edges which may injure workers

• No Recoiling• Remains in place after being installed; does not recoil

• Cost Effective• Creep resistant polyester fibers provide a higher allowable tensile

strength, minimizing the required number of geogrid layers

Page 25: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

GEOGRIDS – WHY POLYESTER (PET)

HDPEreinforcement

Polyesterreinforcement

100 kN/m

75 kN/m

25 kN/m

Same Ultimate tensile strength

Long term design strength

Strain %

Log time (s)21 3 4 5 6 7

10

20

30

1hr 1 d 1yr

PolyethylenePolyamide

Polyester

Polypropylene

Creep at 60% load

Polyester is the strongest design polymer

Analysis of Different High Strength Geosynthetics

Page 26: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

Are extensive independent performance testing studies available?

PULL OUT TESTING

CREEP TESTING

Page 27: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

Mobilization of high tensilestrength at low strain.Wide Range of LTDS (12kNm-180kNm)

Good interlocking and high interface friction.Stable open grid matrix interlocks andInteracts with soil to provide high shearing resistance. The rough surface of grid provides further frictional and shear resistance compared to smooth polyethylene geogrid which relies mainly on interlocking mechanism.

High Strength Polyester Geogrid – Benefits

High resistance toconstruction stress.Protective polymercoating for enhancedchemical and mechanical stressresistance.

Crusher runGeogrid

Interlocking mechanism

Tension

Load

Interface friction0

20

40

60

80

100

0 2 4 6 8 10 12 14Strain (%)

Perc

enta

ge o

f cha

ract

eris

tic sh

ort-t

erm

tens

ile st

reng

th (%

)

Page 28: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

The Geogrid Manufacturer Should

• Have a full complement of geosynthetic testing equipment

• Be Active in developing and maintaining ASTM standards

• Have a GRI-LAP Accredited Laboratory• Be A2LA Accredited• Be ISO 9002 Certified

Page 29: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

“Rumor vs. Fact”’

• RUMOR: POLYESTER GEOGRIDS MAY NOT BE USED IN RECYCLED CONCRETE SOIL BACKFILLS AND HIGH PH SOILS.

• FACT: GEOSYNTHETICS HAVE BEEN TESTED AND INSTALLED IN ALL SOIL TYPES. PET GEOGRIDS ARE SUITABLE FOR ALL SOIL TYPES BASED ON PROPER DESIGN. SEE FHWA ELIAS TECHNICAL PAPER “THE EFFECT OF PH……OF POLYESTER GEOSYNTHETICS”

Page 30: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

Chemical Resistance• PVC coating process binds the molecules for a tighter,

stronger bond resulting in superior durability without cracking or spitting

(FHWA Montana DOT Study)

• PVC is inherently inert to contaminated soils.

(Iowa State University …….impervious to gasoline)

• Service life beyond 120 years

Durability of PET

Page 31: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDSGeogrid Creep Testing

ASTM D5262

• High Creep Resistance

• Over 100,000 hours of creep data

• RFCR PET = 1.47 NTPEP (check with mfg.)

Design Life Exceeds 100 years

Page 32: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDSCreep Rupture Curve : NTPEP

Page 33: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

Independent Evaluation Testing

NTPEP Evaluation• Required by most public

agencies and DOT’s

Page 34: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

NTPEP Installation Damage Testing

Did you know the testing method has changed?

‘Old Test Method’• 200mm fill lift• Moderately-sized compaction

equipment (44 kN)

‘New Test Method’• 150mm fill lift• Large-sized compaction equipment

(111,000 kN)

Page 35: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

NTPEP ALLOWS FOR EASY COMPARISON OF MATERIALS

– NTPEP Published Reports

Property Tensar Strata MirafiCreep (RFcr) 2.68 1.49 1.45

Installation Damage (RFID) Type 3 Silty Sand

1.24 1.24 1.05

Durability (RFD) 1.1 1.15 1.15Total RF 3.66 2.12 1.75

Reduction Factors for Type 3 Backfill (Silty Sand)

Page 36: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

NTPEP ALLOWS FOR EASY COMPARISON OF MATERIALS

– NTPEP Published Reports

Property Tensar Strata MirafiCreep (RFcr) 2.68 1.49 1.45

Installation Damage (RFID) Type 1 Coarse Gravel

2.57 1.88 1.61

Durability (RFD) 1.1 1.15 1.15Total RF 7.58 3.22 2.68

Reduction Factors for Type 1 Backfill (Coarse Gravel)

If LTDS of 18.9 kN/m needed: • Tensar – 143.8 kN/m • Strata – 61.09 kN/m • TenCate – 50.46 kN/m

Page 37: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

“Rumor vs. Fact”

• RUMOR: NEED TO SPECIFY ULTIMATE TENSILE STRENGTH, 95% OF TULT STRENGTH, OR JUNCTION STRENGTH ALONG WITH LTDS.

• FACT: THE DESIGN OF MSE STRUCTURES USES LTDS ONLY. THERE IS NO DESIGN NEED FOR SPECIFYING ULTIMATE TENSILE STRENGTH, 95% OF TULT STRENGTH OR JUNCTION STRENGTH.

Page 38: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

• INDUSTRY ACCEPTED METHOD TO DETERMINE THE LONG TERM USABLE STRENGTH OF A GEOGRID PRODUCT

• SAMPLE CALCULATION, PET IN COARSE GRAVELWIDE WIDTH TENSILE STRENGTH = 50.46 KN/M

RFID = 1.61 RFCR = 1.45RFD = 1.15 (TYPICAL SOIL PH RANGE)

LTDS = WIDE WIDTH TENSILE STRENGTH RFID X RFCR X RFD

LTDS = 50.46 / (1.61 X 1.45 X 1.10) = 18.9 KN/M

Design Properties

Page 39: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

Design Properties

• INDUSTRY ACCEPTED METHOD TO DETERMINE THE LONG TERM USABLE STRENGTH OF A GEOGRID PRODUCT

• SAMPLE CALCULATION, PE GEOGRID IN COARSE GRAVELWIDE WIDTH TENSILE STRENGTH = 143.8 KN/M

RFID = 2.57 RFCR = 2.68RFD = 1.10 (TYPICAL SOIL PH RANGE)

LTDS = WIDE WIDTH TENSILE STRENGTH RFID X RFCR X RFD

LTDS = 143.8 / (2.57 X 2.68 X 1.10) = 18.9 KN/M

Page 40: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

PRODUCT IDENTIFICATION

• MULTIPLE PRODUCT LABELS TO ENSURE EASY IDENTIFICATION

Page 41: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

PET GeogridsKnow what you are getting

Page 42: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

PET GeogridsKnow what you are getting

Made in NA

ISO 9002 Certified manufacturing facility

On-site GAI-LAP accredited geosynthetics lab

Up to date NTPEP evaluation and report

Page 43: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

PET GeogridsKnow what you are getting

Product Certification

Multiple labels on roll

Identification on geogrid itself

Page 44: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

PET GeogridsKnow what you are getting

Extensive connection data, including sustained load connection testing.

Extensive Creep testing, including conventional > 10,000 hours.

Installation damage testing with multiple soil types.

PET yarns that exceed CEG and MW requirements.

Page 45: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

As a designer, how do you protect yourself?

– Thorough and enforceable specifications

– Manufacturer QC Program

– On-site QA Program

Page 46: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

1.6 SUBMITTALS A. Submit the following: 1. Certification: The contractor shall provide to the Engineer a certificate stating the name of the manufacturer, product name, style number, chemical composition of the filaments or yarns, manufacturing location and other pertinent information to fully describe the geosynthetic. The Certification shall state that the furnished geosynthetic meets MARV requirements of the specification as evaluated under the Manufacturer's quality control program. The Certification shall be attested to by a person having legal authority to bind the Manufacturer.

Page 47: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

Page 48: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

Page 49: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

 A. Submit the following:

2. Quality Standards: The contractor shall provide to the Engineer the manufacturer’s Quality Control Plan along with their current A2LA, GAI-LAP, and ISO 9001:2008 certificates.

Page 50: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

Page 51: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

 1.7 QUALITY ASSURANCE A. Manufacturer Qualifications:  The geogrid manufacturer shall have all of the following credentials: Valid NTPEP REGEO report on geogrid material used for this project Geosynthetic Accreditation Institute (GAI) - Laboratory Accreditation Program (LAP) American Association for Laboratory Accreditation (A2LA) ISO 9001:2008 Quality Management System

 B. The geotextile manufacturer shall have a GAI-LAP accredited laboratory at the location of production capable of performing the ASTM tests as outlined in the specification.

Page 52: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

1.8 DELIVERY, STORAGE, AND HANDLING 

A. Geosynthetic labeling, shipment, and storage shall follow ASTM D4873. Product labels shall clearly show the manufacturer or supplier name, style name, and roll number. Product identifications labels, including manufacturers name, product style and roll number shall be included on the outside of the roll packaging material and one the inside of the core of the roll. The material must also be labeled so it is easily identified when deployed.

Page 53: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

Page 54: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

2. Alternate Materials 

A. Alternate geogrid may be considered if the material meets all of the requirements outlined in this specification. In addition to the submittal requirements already outlined, the contractor shall provide the manufacturers submittal that includes the name and address of the original manufacturer, technical data sheets of the products submitted, installation damage reports from a 3rd party accredited laboratory, creep testing data, including conventional data >10,000 hours, connection testing of the geogrid and block combination being submitted as an alternate.

Page 55: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

• As the designer (Engineer of Record), how do you handle requests for alternate materials?

• Geogrid

Alternate Materials

Page 56: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

• There are some quick resources that can help you review alternate geogrids.

• Website

Alternate Materials - Geogrid

Page 57: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

Page 58: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

• There are some quick resources that can help you review alternate geogrids.

• Website• Geosynthetics Specifier’s Guide

Alternate Materials - Geogrid

Page 59: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

Alternate Materials - Geogrid

• Suppliers submit material for inclusion.

• There is no review or audit of the material submitted.

Page 60: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

• There are some quick resources that can help you review alternate geogrids.

• Website• Geosynthetics Specifier’s Guide• Who is the original geogrid

manufacturer?• NTPEP

Alternate Materials - Geogrid

Page 61: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

SPECIFYING GEOGRIDS

• There are some quick resources that can help you review alternate geogrids.

• Website• Geosynthetics Specifier’s Guide• Who is the original geogrid manufacturer?• NTPEP• Request actual test data for creep, ID, and

pullout.• If PET, request CEG and MW certs.

Alternate Materials - Geogrid

Page 62: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

Geosynthetics and MSE Walls – Design BasicsMSE WALL COMPONENTS

Page 63: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

WHAT ARE MECHANICALLY STABILIZED EARTH WALLS?• Mechanically Stabilized Earth (MSE) walls are retaining walls or grade

separation devices

• MSE walls utilize a reinforced soil gravity mass to resist external forces

• Reinforced soil is created through the use of horizontal soil reinforcing elements and compacted backfill material.

Page 64: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

COMPONENTS

• Soil Reinforcement

• Backfill Material

• Facing Unit

TYPICAL MSE RETAINING WALL

Page 65: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

GEOSYNTHETICS • Uniaxial Geogrids• High Strength Woven Geotextile

METALLIC• Steel Grids• Smooth or Ribbed Steel Strips

SOIL REINFORCEMENT OPTIONS

Page 66: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

BACKFILL MATERIAL

• Gradation Requirements as per AASHTO LRFD Construction Specification

Sieve Size Percent Passing (%) 100 mm (4.0 in.) 100 4.25 mm (No. 40) 0 – 60 75 μm (No. 200) 0 – 15

• Free draining, granular material typically recommended for soil reinforcement backfill

• Minimum backfill compaction is typically 95% Standard Proctor Maximum Dry Density (SPMDD)

Page 67: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

LONG TERM DESIGN STRENGTH

𝐿𝑇𝐷𝑆=𝑇𝑢𝑙𝑡

𝑅𝐹 𝐼𝐷×𝑅𝐹𝐶𝑅×𝑅𝐹𝐷

Installation Reduction Factors, RFID

GeosyntheticsType 1 Backfill Type 2 Backfill

Max. Size 4" (100mm) Max Size 3/4" (20mm)D50 about 1-1/4" (30mm) D50 about #30 (0.7mm)

HDPE Uniaxial Geogrid 1.20 - 1.45 1.10 - 1.20 PP Biaxial 1.20 - 1.45 1.10 - 1.20PVC coated PET Geogrid 1.30 - 1.85 1.10 - 1.30Acrylic coated PET geogrid 1.30 - 2.05 1.20 - 1.40Woven Geotextiles (PP & PET)a 1.40 - 2.20 1.10 - 1.40Non Woven Geotextiles (PP & PET)a 1.40 - 2.50 1.10 - 1.40Slit Film Woven PP Geotextilea 1.60 - 3.00 1.10 - 2.00a. Minimum Weight 8.0 oz/yd2 (270 g/m2)

Creep Reduction Factor, RFCR

Polymer Type Creep Reduction FactorPolyester (PET) 2.5 - 1.6

Polypropylene (PP) 5.0 - 4.0High Density Polyethylene (HDPE) 5.0 - 2.6

Page 68: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

DESIGN CONSIDERATIONS

• Wall Height

• Wall Batter

• Backfill Slope

• Surcharges

• Water Table Elevation

Page 69: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

Geosynthetics and MSE Walls – Design BasicsANALYSIS OF MSE WALLS

Page 70: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

MSE WALL DESIGN METHODS

Design Methods most commonly used and are Industry Accepted Standard of Practice are:

• National Concrete Masonry Association (NCMA)• Used most frequently for Private Works• Design Manual “Segmental Retaining Walls” is currently in its Second Edition, although it is

currently being revised.

• Federal Highway Administration (FHWA)• Used most frequently for Public Works• Design Manual “FHWA NHI-00-043, 044, Mechanically Stabilized Earth Walls and

Reinforced Steepened Slopes, Design and Construction Guidelines” is currently in its Second Edition, first Edition was known as “Demo 82”

• Developed following AASHTO LRFD Bridge Design Specifications and AASHTO LRFD Bridge Construction Specifications.

Page 71: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

MSE WALL ANALYSIS

External Stability

Sliding Movement

Sliding Resistance

Sliding Resistance

Sliding Overturning

Overturning Movement

Page 72: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

MSE WALL ANALYSIS

Bearing Capacity Settlement

Movement

External Stability

Page 73: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

MSE WALL ANALYSIS

Internal Stability

Connection Tension Pullout

Units Active Wedge Passive Zone

Page 74: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

PULLOUT RESISTANCE

= Pullout Resistance = Pullout Resistance Factor = Correction factor = Effective Vertical Stress at the soil-reinforcement interface = The embedment length in the resisting zone behind the failure plane = The reinforcement effective unit perimeter (ex. = 2 for grids)

= peak friction angle of soil

SOIL TYPE

Gravel 30° – 50°

Sand and Gravel with fine grained soils

30° – 40°

Sand 32° – 50°

Silt and Silty Sand 27° – 35°

Clay 20° – 30°

Page 75: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

MSE WALL ANALYSIS

Internal Stability

Overturning

Bending Bulging

Shear

Page 76: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

MSE WALL ANALYSIS

Compound and Overall (Global) Stability

Page 77: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

Geosynthetics and MSE Walls – Design BasicsMSE WALL TYPES & FACING OPTIONS

Page 78: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

MSE WALL TYPES

TEMPORARY (36 month life span)• Geotextile Wrapped• Welded Wire Mesh / Geotextile

PERMANENT • Welded Wire Mesh with Geogrid• Geocell with Geogrid• Binwall with Geogrid

Page 79: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

TEMPORARY MSE WALLS

Page 80: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

MSE WALL CONSTRUCTION - WRAPPED FACESTEP 1

1. Check level of base

2. Check all line, grade and curves

3. Place removable form at front of reinforced mass

4. Install first layer of geotextile over removable form

Removable formGeotextile Reinforcement

Native Soil

Page 81: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

STEP 21. Pull Geotextile tight, keep tension applied

until backfill is placed.

Compacted fill

Native Soil

Depression for geotextile wrap

Removable form

2. Place backfill in specified lifts and compact to 95% Standard Proctor Dry Density.

MSE WALL CONSTRUCTION

Page 82: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

STEP 3

1. Wrap geotextile back over compacted fill

2. Place & compact fill above upper wrap portion and level

Native Soil

Fill on top of geotextile

MSE WALL CONSTRUCTION

Page 83: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

STEP 41. Place second removable form by repeating step 1.

(provide required batter with set back)

Native Soil

2. Place second layer of geotextile and reinforced fill by repeating steps 2 through 3.

3. After completion of second lift, remove the first form.

MSE WALL CONSTRUCTION

Page 84: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

MSE WALL CONSTRUCTION

1. Repeat steps 1 through 3 until wall is at required height

Native Soil

Finished Grade

Page 85: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

High Performance Woven Geotextile

• Geotextile Wrapped

TEMPORARY MSE WALLS

Page 86: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

TEMPORARY MSE WALLS• Wire Mesh / Geotextile Walls

Page 87: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

PERMANENT MSE WALLS• Reinforcement and Fascia

Page 88: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

MSE WALL SYSTEMS

Welded Wire Mesh Face / Geogrid

Finished Grade

Reinforced Soil Zone

FOUNDATION SOIL ZONE

Native Soil

GeosyntheticReinforcement

Welded Wire Fascia

Page 89: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

Wire Mesh with Geogrid(Rock Faced)

Cobourg, ON

Page 90: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

GEOCELL

Abbotsford, BC

Page 91: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

Wire Mesh With Geogrid

(Vegetated Face)

Oakville, ON

Page 92: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

q = SURCHARGE

Geogrid ReinforcementFinished Grade

Reinforced Soil Zone

Foundation Soil Zone

Native SoilGeocell Fascia

Geocell with Geogrid MSE Walls

Page 93: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

GEOCELL

Page 94: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

GEOCELL

Page 95: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

GEOCELL

Newmarket, ON

Page 96: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

GEOCELL

Page 97: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

BIN WALL WITH GEOGRID

Page 98: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

BIN WALL WITH GEOGRID

Mississauga, ON

Page 99: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

Contact Your Local Sales Rep:www.armtec.com/sales-offices/

Todays Speakers:

Michael [email protected]

Andrew ListerMirafi® Geosynthetics, TenCate Geotube®

Page 100: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

UPCOMING WEBINARS

For more info please visit www.armtec.com/events

Remember – For CPD certificates, send names & emails to [email protected]!

Fall Webinar Series Coming Soon!

Stay tuned for updates!

Page 101: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

STAY CONNECTED!

Armtec respects your privacy. All communications comply with CASL and general best practices. For more information, you can find links to privacy policy and options to unsubscribe in footer of any emails.

On Social Media On armtec.com WebinarsFollow us! After the webinar fill out our

survey and click yes!Fill out the form at armtec.com

and stay up to date on the latest/armtecltd

/ArmtecLtd

/company/armtec

See our presentation on SlideShare and YouTube!

Page 102: MSE Walls & Geosynthetics - Design Basics Webinar April 2016

Contact Your Local Sales Rep:www.armtec.com/sales-offices/

Todays Speakers:

Michael [email protected]

Andrew ListerMirafi® Geosynthetics, TenCate Geotube®


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