A Guide to Polymeric Geomembranes: A Practical Approach

Series Preface xvii

Preface xix

About the Author xxi

Acknowledgments xxiii

1 Introduction to Polymeric Geomembranes 1

1.1 Introduction 1

1.2 Viscoelastic Behaviour 2

1.3 Polymer Structure 4

1.4 Molecular Weight 5

1.5 Molecular Weight Distribution 7

1.6 Crystallinity 8

1.7 Properties of Polyethylenes 14

1.8 Stress–Strain Behaviour of Polymers 16

1.9 Melting Points 20

References 20

2 Geomembrane Manufacturing Methods 21

2.1 Blown Film (Round Die) 22

2.2 Flat Sheet Extrusion (Flat Die) 23

2.3 Coextrusion 25

2.4 Calendering 28

2.5 Spread Coating 29

2.6 Extrusion Coated Geomembranes 30

2.7 Pin-Hole Detection 30

2.8 Texturing 30

2.9 Additives for Geomembranes 40

References 51

3 HDPE Geomembranes 53

3.1 Introduction 53

3.2 Structure–Property Relationships 59

3.3 Comparison of HDPE Geomembranes with Other Geomembranes 60

3.4 Durability and Survivability of HDPE 60

3.5 Selection of Quality HDPE Geomembranes 63

3.6 Common Failure Modes of HDPE Geomembranes 75

3.7 Multilayer HDPE Geomembranes 77

3.8 Fluorinated HDPE (F-HDPE) 82

References 88

4 Linear Low-Density Polyethylene Geomembranes 91

4.1 Introduction 91

4.2 Attributes of LLDPE Geomembranes 92

4.3 Limitations of LLDPE Geomembranes 92

4.4 Mechanical Properties 92

4.5 LLDPE Geomembrane Resins 94

4.6 Speciality Flexible Polyethylene Geomembranes 95

4.7 Very Low-Density Polyethylene (VLDPE) Geomembranes 100

References 100

5 Flexible Polypropylene (fPP) Geomembranes 101

5.1 Introduction 101

5.2 Attributes of fPP Geomembranes 102

5.3 Shortcomings of fPP Geomembranes 102

5.4 Performance Propeties of fPP Geomembranes 104

5.5 Applications 112

5.6 fPP Field Failures 112

References 115

6 CSPE Geomembranes 117

6.1 Introduction 117

6.2 Grades of Hypalon J n117

6.3 Attributes of CSPE Geomembranes 118

6.4 Limitations of CSPE Geomembranes 119

6.5 General Properties of CSPE Geomembranes 120

6.6 Comparisons of CSPE with Other Geomembranes 125

6.7 Applications of CSPE Geomembranes 125

6.8 Chemical Resistance of CSPE Geomembranes 125

References 126

7 PVC Geomembranes 127

7.1 Introduction 127

7.2 Attributes of PVC Geomembranes 130

7.3 Shortcomings of PVC 132

7.4 Properties of PVC Geomembranes 133

7.5 Failure Modes 134

7.6 Formulation of PVC Geomembranes 136

References 138

8 EIA Geomembranes 139

8.1 Introduction 139

8.2 Attributes of EIA-R Geomembranes 141

8.3 Limitations of EIA-R Geomembranes 142

8.4 Performance Properties of EIA-R Geomembranes 142

8.5 Comparison of EIA-R (XR-5 _) Versus CSPE-R (Hypalonᄢ) Geomembranes 147

8.6 Application Areas for EIA-R Geomembranes 147

References 148

9 EPDM Geomembranes 149

9.1 Introduction 149

9.2 Attributes of EPDM Geomembranes 149

9.3 Structure and Chemistry 151

9.4 Mechanical Properties 152

9.5 Advantages of EPDM over HDPE Geomembranes (Property Comparison) 153

9.6 Comparison between EPDM and PVC Geomembranes 158

9.7 Seaming EPDM Geomembranes  160

9.8 Applications 161

9.9 Service Life 161

References 162

10 Bituminous Geomembranes (BGMs) 163

10.1 Introduction 163

10.2 Prefabricated Bitumen Membranes 163

10.3 Composition and Construction 164

10.4 Longevity of Bituminous Geomembranes 165

10.5 Spray-in-Place Bitumen Membranes166

10.6 Design Life of Bituminous Geomembranes 167

References 167

11 Specialty Geomembranes and Liners 169

11.1 EVA Liners/Geomembranes 169

11.2 Butyl Rubber Liners 170

11.3 Nitrile Rubber Geomembranes 172

11.4 Chlorinated Polyethylene (CPE) 175

11.5 Polyurethane (PU) Geomembranes 176

11.6 Acrylic-Coated Geomembranes/Geotextile Composites 178

11.7 PVDF Liners 180

11.8 Chemical Vapour Barrier Membranes 182

References 187

12 Key Performance Properties of Geomembranes 189

12.1 Specific Gravity (Density) 189

12.2 Mass per Unit Area 191

12.3 Thickness 192

12.4 Melting Point 196

12.5 Melt Flow Index 198

12.6 Thermal Expansion 199

12.7 Flexibility 203

12.8 Conformability for Intimate Contact 204

12.9 Ability to Resist/Accept Stress and Deformation 204

12.10 Tensile Properties 206

12.11 Puncture Resistance 213

12.12 Tear Resistance 217

12.13 Ply Adhesion of Reinforced Geomembranes 219

12.14 Resistance to Stress Cracking 220

12.15 Frictional Properties 226

12.16 Low-Temperature Properties 232

12.17 High-Temperature Capabilities 236

12.18 Oxidative Resistance 236

12.19 UV Resistance 240

12.20 Permeability of Geomembranes 241

12.21 Durability 245

12.22 Application Specific Performance Properties  249

12.23 Comparison of Performance Properties of Flexible Geomembranes 251

References 251

13 Testing of Geomembranes 255

13.1 Material Property Testing 255

13.2 Measuring Thickness 256

13.3 Density 258

13.4 Mass per Unit Area 259

13.5 Tensile Testing Methods 259

13.6 Tear Testing 266

13.7 Ply Adhesion 268

13.8 Puncture Resistance 269

13.9 Impact Resistance 275

13.10 Environmental Stress Cracking 276

13.11 Dimensional Stability 283

13.12 Friction Angles 284

13.13 Melt Flow Index (MFI) 284

13.14 Durability Testing 286

13.15 Tests for Additives 294

13.16 Carbonyl Index Measurements 303

13.17 Chemical Resistance Testing 305

References 309

14 Chemical Resistance of Geomembranes 313

14.1 Chemical Resistance Tables 314

14.2 Factors Affecting Chemical Resistance 315

14.3 Effects of Chemicals on Geomembranes 322

14.4 Chemical Resistance Testing 322

14.5 Geomembrane Chemical Resistance by Chemical Class 329

14.6 Geomembrane Chemical Resistance by Polymer Type 335

14.7 Environmental Stress Cracking 339

References  341

15 Failure Modes of Geomembranes 343

15.1 Potential for Geomembrane Damage 343

15.2 Failure of Installed Geomembranes 344

References 368

16 Application Areas for Geomembranes 371

16.1 Landfill Liners 371

16.1.1 Design Aspects 373

16.2 Landfill Caps/Covers 374

16.3 Mining Applications 378

16.4 Floating Covers 386

16.5 Tank Liners 394

References 399

17 Welding of Geomembranes 401

17.1 Wedge Welding 401

17.2 Hot Air Fusion Welding 413

17.3 Extrusion Welding 415

17.4 General Overview of Thermal Welding Methods 424

17.5 Potential Thermal Welding Problems 425

17.6 Defects that can Affect Weld Integrity 429

17.7 Trial Welds and Field Welds 437

17.8 Chemical Welding of Geomembranes 440

17.9 General Welding Instructions for HDPE/LLDPE/fPP Geomembranes 442

17.10 General Welding Instructions for PVC Geomembranes 445

References 447

18 Geomembrane Weld Testing Methods 449

18.1 Introduction to Weld Testing 449

18.2 Visual Inspection of Welds 450

18.3 Nondestructive Seam Tests 453

18.4 Destructive Weld Tests 465

18.5 Forensic Weld Examination 484

18.6 Leak Location Testing 485

References 489

19 Geomembrane Installation Factors 491

19.1 Introduction 491

19.2 Design Considerations 493

19.3 Installation and Damage Considerations 496

References 531

Appendix 1 Glossary 533

References 546

Appendix 2 Geomembrane Test Methods 547

American Society for Testing and Materials 547

Geomembrane (GM) Related Test Methods and Standards from GRI 549

Geomembrane Testing Methods Conversion Table ASTM and ISO 551

Index 553