HANDBOOK OF PORT AND HARBOR ENGINEERING

JOIN US ON THE INTERNET WWW: http:/ /www.thomson.com

EMAIL: findit@kiosk.thomson.com thomson.com is the on-line portal for the products, services and

resources available from International Thomson Publishing (ITP). This Internet kiosk gives users immediate access to more than 34 ITP publishers and over 20,000 products. Through thomson.com Internet users can search catalogs, examine subject-specific resource centers and subscribe to electronic discussion lists. You can purchase ITP

products from your local bookseller, or directly through thomson.com.

Visit our Internet Resource Center for information on our new publications, links to useful sites on the World Wide Web and an opportunity to join our e-mail mailing

list. Point your browser to: http://www.chaphall.com/chaphall.html or http://www.chaphall.com/chaphall/civeng.html for Civil Engineering

~® A service of I\!) P

HANDBOOK OF PORT AND HARBOR ENGINEERING

GEOTECHNICAL AND STRUCTURAL ASPECTS

Gregory P. Tsinker, Ph.D., P.E.

Springer-Science+Business Media, B.V.

Cover Design: Andrea Meyer, emDASH inc., New York, NY Cover Photo: Courtesy of Han-Padron Associates, New York, NY

Copyright © Springer Science+Business Media Dordrecht 1997

Originally published by Chapman & Hall in 1997

ISBN 978-1-4757-0865-3 ISBN 978-1-4757-0863-9 (eBook) DOI 10.1007/978-1-4757-0863-9

All rights reserved. No part of this work covered by the copyright hereon may be reproduced or used in any form or by any means-graphic, electronic, or mechanical, including photocopying, recording, taping, or information storage and retrieval systems-without the written permission of the publisher.

12345678910XXXOI 009997

Library of Congress Cataloging-in-Publication Data

Tsinker, Gregory P. Handbook of port and harbor engineering : geotechnical and structural aspects I Gregory P. Tsinker.

p. em. Includes bibliographical references and index. ISBN 978-1-4757-0865-3 I. Harbors-Design and construction. 2. Marine geotechnique. I. Title.

TC205.T747 1996 627' .2-dc20 95-48487

CIP

British Library Cataloguing in Publication Data available

To order this or any other Chapman & Hall book, please contact International Thomson Publishing, 7625 Empire Drive, Florence, KY 41042. Phone: (606) 525-6600 or 1-800-842-3636. Fax: (606) 525-7778, e-mail: order@chaphall.com.

For a complete listing of Chapman & Hall's titles, send your requests to Chapman & Hall, Dept. BC, 115 Fifth Avenue, New York, NY 10003.

To Nora

v

contents

Dedication v

Preface xix

Introduction xxv

Contributors xxxvii

1 THE MARINE ENVIRONMENT AND ITS EFFECTS ON PORT DESIGN AND CONSTRUCTION 1

1.1 Introduction 1

1.1.1 General 1 1.1.2 Seawater and Fouling 4

1.2 Water-level Variations 8

1.3 Weather Factors 10

1.4 Wind 12

1.4.1 General 12

vii

viii Contents

1.4.2 Wind Parameters 14

1.5 Currents

1.6 Waves

1.6.1 General 19 1.6.2 The Sea State Parameters 26 1.6.3 Wave Theories 31 1.6.4 Design Wave 33

16

19

1.7 Ice 37

1.7.1 Introduction 38 1.7.2 Ice Covers 39 1.7.3 Effects of Ice on Port Operations 47 1.7.4 Cold Temperature and Ice Effects on Marine Structures Design 54

References 61

2 PORT (HARBOR) ELEMENTS: DESIGN PRINCIPLES AND CONSIDERATIONS

2.1 General

2.1.1 Port Classification 70 2.1.2 Port Details and Definitions 71

2.2 Ships and their Influence on Port Design

2.2.1 Ships 73 2.2.2 Ship Influence on Port Design 7 4

2.3 Access (Navigation) Channel

2.3.1 General 78 2.3.2 Navigational and Operational Parameters 79 2.3.3 Environmental Parameters 81 2.3.4 Layout 82 2.3.5 Channel Cross Section 84 2.3.6 Economic Considerations 96

69

69

73

78

Contents ix

2.4 Port (Harbor) Entrance 98

2.5 Port Water Area (Harbor) 106

2.5.1 Basin Sizes 107

2.6 Location, Orientation, Size, and Shape of the Port 112

2.6.1 Selection of Port Location 112 2.6.2 Size and Orientation of Marine Facilities 115 2.6.3 Harbor Area Requirements 115

2.7 Quay Basin 119

2.8 Offshore Installations 121

2.8.1 Offshore Bottom-Fixed Marine Facilities 121 2.8.2 Single-Point Offshore Moorings 123

2.9 Port-Related Marine Structures

2.9.1 Land Requirements 124 2.9.2 Dust and Noise Control 127 2.9.3 Berth Requirements 128 2.9.4 Structures 130

124

2.9.5 Selection of the Most Cost Effective Structure for Dock Construction 151 2.9.6 Constructability 153

2.10 Structural Materials

2.10.1 Structural Concrete 155 2.10.2 Underwater Concreting 172 2.10.3 Precast Concrete 178 2.10.4 Structural Steel in Port Engineering 180 2.10.5 Structural Timber 195

2.11 Breakwaters

2.12 In-Harbor Slope Protection

2.13 Aids to Navigation

2.14 Mooring Accessories

154

198

203

204

205

x Contents

2.15 Fender Systems

2.15.1 Timber Fenders 208 2.15.2 Solid Rubber Fenders 210 2.15.3 Pneumatic Fenders 216 2.15.4 Foam-Filled Fenders 222 2.15.5 Other Fender Systems 222 2.15.6 Fenders Failure 226 2.15.7 General Principles in Fender System Selection and Design 226

206

References · 232

3 DESIGN LOADS

3.1 General

3.2 Environmental Loads

3.2.1 Wind 245 3.2.2 Currents 248 3.2.3 Waves 251

3.3 Mooring Loads

3.3.1 Mooring Lines Arrangement 261 3.3.2 Mooring Line Materials 262 3.3.3 Mooring Forces 262

3.4 Loads From Cargo Handling and Hauling Equipment and Uniform

243

243

244

260

Distributed Loads 267

3.4.1 General Considerations 267 3.4.2 Design Load Assumptions 269 3.4.3 Uniform Distributed Cargo Loads and Miscellaneous Live Loads 271 3.4.4 Rubber Tire and Crawler Track Mounted Equipment 272 3.4.5 Rail-Mounted Cargo 279 3.4.6 Fixed-Base Equipment 282

3.5 Ship Impact (by M. Shiono in collaboration with G. Tsinker)

3.6 Ice Loads

3.6.1 General 293 3.6.2 Environmental Driving Forces 294 3.6.3 Ice-Crushing Load 295 3.6.4 Loads Due to Ice Bending Mode of Failure 297

283

293

Contents xi

3.6.5 Forces Due to Ice Sheet Adfreeze to the Structure 299 3.6.6 Vertical Loads on Piles or Piers Due to Changes in Water Level 300 3.6.7 Ice Load of Thermal Origin 301 3.6.8 Other Ice-Induced Loads 302

3.7 Seismic Loads (by W. S. Dunbar) 3.7.1 Seismic Ground Motion 303 3.7.2 Descriptions of Ground Motion 307 3.7.3 Design Ground Motion Estimation 312 3.7.4 Design Loads 318

302

3.8 Load Combinations 319

References 320

4 GEOTECHNICAL ASPECTS OF SOIL-STRUCTURE INTERACTION DESIGN CONSIDERATIONS 331

4.1 General 331

4.2 Subsurface Investigation 333

4.3 Soil Liquefaction and Evaluation of Liquefaction Potential (by G. Tsinker and W. S. Dunbar) 334

4.4 Basic Design and Construction Considerations 342

4.4.1 Modern Trends 342 4.4.2 Bottom-Fixed Structures 343 4.4.3 Safety Considerations 345 4.4.4 Construction Procedure 347

4.5 Soils and Bedrock

4.5.1 Gravel and Sand 348 4.5.2 Silt and Clay 349 4.5.3 Bedrock 350

4.6 Properties and Characteristics of Soils

4.6.1 Shear Strength 354 4.6.2 Compressibility (Consolidation) 356 4.6.3 Permeability 357

348

352

xii Contents

4.7 Lateral Soil Pressure

4.7.1 Active Earth Pressure 359 4. 7.2 Effects of Wall Movement 368 4.7.3 Effects of Time-Dependent Changes in Soil 374 4.7.4 Effect of Ambient Temperature on Earth Pressures 376 4. 7.5 Effects of Backfill Freezing 376 4.7.6 Passive Earth Pressure 376 4. 7. 7 Earth Pressure at Rest 380 4.7.8 Compaction-Induced Pressure 381

4.8 Friction Forces on Walls

4.9 Dynamic Soil Pressures

4.9.1 Mononobe-Okabe Formulation 383 4.9.2 Effect of Saturated Backfill 385 4.9.3 Hydrodynamic Pressures 385 4.9.4 Effect of Wall Inertia 386 4.9.5 Selection of Ground Motions 387 4.9.6 Effect of Wall Movements 387

358

381

382

References 388

5 GRAVITY-TYPEQUAYWALLS

5.1 General

5.2 Basic Structural Arrangements

5.2.1 Blockwork Structures 403 5.2.2 Quay Walls Composed of Floated-in Concrete Caissons 409 5.2.3 Quay Walls Composed of Large-Diameter Cylinders 428 5.2.4 Cribwork Quay Walls 435 5.2.5 Steel Sheet-Pile Cell Bulkheads 439 5.2.6 Quay Walls 446 5.2.7 Gravity-Type Walls 452

5.3 Basic Design Considerations

5.3.1 Loads and Forces Load Combinations 461 5.3.2 Basic Static Principles 464

5.4 Design ofBlockwork Quay Walls

5.4.1 Basic Design Principles 478

397

397

403

461

478

Contents xiii

5.4.2 Design Phase 1 480 5.4.3 Design Phase 2 483 5.4.4 Design Phase 3 484 5.4.5 Design Phase 4 484

5.5 Design of Quay Walls Comprised of Floated-in Concrete Caissons

5.5.1 Basic Design Principles 485 5.5.2 Buoyancy and Buoyant Stability of a Caisson 485 5.5.3 Buoyancy and Stability of a Damaged Caisson 489 5.5.4 Caisson Launch 490 5.5.5 Towing and Sinking 496 5.5.6 Structural Design 497

5.6 Design of Quay Walls Composed of Large-Diameter Cylinders

5.7 Design ofL-Shaped Walls

5.7.1 Basic Requirements 504 5.7.2 Design of Cantilever Walls 506 5.7.3 Design of Counterfort Wall 507 5.7.4 Design of Wall Constructed from Prefabricated Components with

Internal Anchorage 508 5.7.5 Design of Wall Constructed from Prefabricated Components with

External Anchorage 508

5.8 Design of Cellular-type Steel Sheet-pile Bulkheads

5.8.1 Introduction 511 5.8.2 Conventional Design Method 512 5.8.3 Horizontal Shear (Cummings') Method 518 5.8.4 Brinch Hansen Method 519 5.8.5 Seismic Design of Cellular Bulkheads 519 5.8.6 Deflection of Cellular Bulkhead 520 5.8.7 Effects of Concentrated Horizontal Loads on Sheet-Pile Cell 522

5.9 Design ofCribwork-type Quay Walls

5.10 Reinforced Earth Quay (by D. Weinreb and P. Wu)

5.10.1 General Concept 524 5.10.2 Design of Reinforced Earth Marine Structures 532 5.10.3 Construction of Reinforced Earth Walls Underwater 536

References

485

500

504

511

522

524

542

xiv Contents

6 SHEET-PILE BULKHEADS

6.1 Introduction

6.1.1 Sheet-Piling-Background 549 6.1.2 Anchoring Systems 552 6.1.3 Sequence of Construction 555

6.2 Sheet-Piling-Structural and Driving Aspects

6.2.1 Timber Sheet Piles 556 6.2.2 Steel Sheet Piles 558 6.2.3 Concrete Sheet Piles 561 6.2.4 Selection of Sheet-Pile Section 570

6.3 Anchor Systems

6.3.1 Anchor System Comprised of Tie-Rods and Anchorages 572 6.3.2 Anchor System Comprised of Raked Piles 576 6.3.3 Ground (Rock) Anchors 583

6.4 Wall Capping

6.5 Construction Methods

6.5.1 Construction Sequence 591 6.5.2 Sheet-Pile Driving 592 6.5.3 Pile Jetting 596 6.5.4 Earthwork 602

6.6 Earth Pressures on Flexible Walls: State-of-the-Art Review

6.7 Design of Sheet-pile Walls

6.7.1 Design Criteria 623 6.7.2 Design of Cantilever Walls 625 6. 7.3 Design of Anchored Bulkheads 630 6.7.4 Design of Sheet-Pile Bulkheads Anchored by Raked Piles 643

6.8 Sheet-Pile Bulkheads Built on Creep Soils

6.8.1 Cantilever Sheet-Pile Bulkhead 655 6.8.2 Single-Anchor Sheet-Pile Bulkhead 657 6.8.3 Multianchor Sheet-Pile Bulkhead 661

6.9 Anchorage Design

549

549

555

571

589

591

606

623

653

665

6.9.1 Piled Anchorages 666 6.9.2 Sheet-Pile Anchor Wall 667 6.9.3 Individual Vertical Anchor Piles 669 6.9.4 Deadman (Plate) Anchor 670

6.10 Waling and Tie-Rod Design

6.11 Ground (Rock) Anchors

6.12 Overall Stability

6.13 Seismic Design of Anchored Sheet-Pile Walls (by W. S. Dunbar)

6.13.1 Observed Failure Modes 682 6.13.2 Seismic Design Procedure 683 6.13.3 Assumption 683 6.13.4 Factor of Safety Against Failure by Rotation 683 6.13.5 Size and Location of Anchor Block 684 6.13.6 Balanced Design Procedure 685

6.14 Sheet-Pile Wall Failure

References

7 PILED WATERFRONT STRUCTURES

7.1 Introduction

7.2 General

7.2.1 Structural Schemes and Structural Components 697 7.2.2 Prefabrication 701

Contents xv

672

673

679

682

686

688

695

695

697

7.3 Open Pile Structures With Suspended Decks 701

7.3.1 Open Piled Offshore Piers 702 7.3.2 Piling 710 7.3.3 Suspended Deck Structures for Marginal Wharves 711 7.3.4 Basic Design Principles 712 7.3.5 Suspended Deck Structures Founded on Large-Diameter Cylindrical Piles

718 7.3.6 Protection from Ship Impact 722

xvi Contents

7.4

7.5

7.6

7.7

7.3.7 Pile Anchoring in Foundation Soil and the Deck Structure 724

Relieving Platforms

Structural Elements

7.5.1 Pile Foundation 735 7.5.2 Superstructure 776 7.5.3 U nderdeck Slope 782

Pile-Soil Interaction

7.6.1 General 795 7.6.2 Piles Under Axial Static Load 803 7.6.3 Pile Settlement 817

Laterally Loaded Piles

7.7.1 General 820 7.7.2 Conventional Design Methods 822 7.7.3 Broms' Method 826 7. 7.4 Subgrade Reaction Approach 829 7.7.5 Laterally Loaded Socketed Piles 836

7.8 Piled Marine Structures Design Methods

7.8.1 Design Criteria 837 7.8.2 Design Methods 838

References

8 OFFSHORE DEEP WATER TERMINALS

8.2 Layout

8.2.1 Dry Bulk Loading/Unloading Facilities 882 8.2.2 Liquid Bulk Loading/Unloading Terminals 886

8.3 Mooring System 8.3.1 Basic Structural Concepts 890

8.4 Dolphins and Platforms

8.4.1 Breasting Dolphins 893 8.4.2 Piled Breasting Dolphins 895 8.4.3 Gravity-Type Dolphins 896

725

734

795

820

837

865

879

881

888

893

Contents x:vii

8.4.4 Steel Jacket-Type Structures 898 8.4.5 Fenders 898 8.4.6 Mooring Dolphins 898 8.4.7 Loading/Unloading Platforms 899 8.4.8 Access Trestles and Catwalks 899

8.5 Structural Design

8.5.1 Marine Foundation and its Effects on Structural Design 901 8.5.2 Basic Design Procedures 903

References

9 MODERNIZATION OF EXISTING MARINE FACILITIES

9.1 Introduction

9.2 Modernization of Mooring Structures

9.2.1 Modernization of Gravity-Type Quay Walls 920 9.2.2 Modernization of Piled Wharves 925 9.2.3 Modernization of Sheet-Pile Bulkheads 925 9.2.4 New Wall Construction 929

9.3 Modernization of Waterfront Structures: Characteristic Examples

9.3.1 Gravity-Type Quay Walls 930

901

914

917

917

919

930

9.3.2 Modification of Piled Coal-Loading Pier No. 6 at Norfolk, Virginia 940 9.3.3 Use of Piled Structures and Sheet-Pile Walls for Modernization

of Existing Structures 942 9.3.4 Construction of Brand New Structures 949

References

10 BREAKWATER DESIGN (by S. Takahashi)

10.1 Historic Development of Breakwaters

10.1.1 Structural Types 952 10.1.2 Conditions for Breakwater Selection 956 10.1.3 Comparison of Sloping- and Vertical-Type Breakwaters 956 10.1.4 Historical Development of Breakwaters 957

10.2 Design of Conventional Vertical Breakwaters

949

951

952

977

xviii Contents

10.2.1 Examples of Conventional Vertical Breakwaters 977 10.2.2 Wave Transmission and Reflection by Vertical Walls 978 10.2.3 Wave Forces on Vertical Walls 981 10.2.4 Design of Rubble-Mound Foundation 1001 10.2.5 Rubble-Mound Toe Protection Against Scouring 1005

10 .. 3 Design of New Types ofVertical Breakwater

10.3.1 Perforated Wall Breakwater 1007 10.3.2 Inclined Walls 1015

10.4 Design of Horizontally Composite Breakwaters

10.4.1 Wave Transmission and Reflection 1021 10.4.2 Wave and Block Load on a Vertical Wall 1022 10.4.3 Stability of Wave-Dissipating Concrete Blocks 1023

1006

1020

10.5 Design of Rubble-Mound Breakwaters 1024

10.5.1 Wave Transmission and Reflection 1025 10.5.2 Design of Armor Layer 1027 10.5.3 Inner Layers, Core, Toe, and Wave Screen 1034

References 1036

Index 1045

Preface

In past 10 years or so several excellent books and handbooks on "Port and Harbors Engineering" and "Coastal and Ocean Engi­neering" have been published in Europe and in North America. Reference to these works is made elsewhere in this book.

The authors of the aforementioned works offer a shrewd and comprehensive discus­sion on the marine environment and its effects on port design, port operation, port hydraulics, coastal geomorphology, littoral drift and sedimentation, port and shipping technology and economics, design and con­struction of a floating port related struc­tures, and others. However, proportionally the geotechnical and structural aspects of port construction have been given very lit­tle attention. This happens, perhaps, be­cause the subject of marine structures engi­neering is very broad by itself; it is a blend that encompasses the array of engineering disciplines, e.g., civil, structural, geotechni­cal, hydraulic, strength of materials, corro­sion, naval architecture and others knowl­edge of which is required to produce a sound and economical design of a modern port or marine terminal.

This book has been written to :fill a niche in the existing literature on port and harbor engineering and to provide the port design­ers, and particularly those concerned with the design of a port- and harbor-related marine structures, with state-of-the-art in­formation and common sense guidelines to the design and construction of the basic types of marine structures. This book is a companion volume to my earlier work Ma­rine · Structures Engineering: Specialized Applications published by Chapman & Hall in 1995. That book covers important sub­jects such as the evaluation of capacity of the in-service marine structures and meth­ods of their remediation and maintenance, construction and operation of the marine structures in cold regions, design and con­struction of a shipyard and related marine structures, design of anchored offshore moorings and floating breakwaters, design and construction of marinas (small craft harbors), and design and construction of marine structures that are used in naviga­ble waterways for protecting the bridge piers from ship collision. Conversely, this

xix

xx Preface

volume provides the marine structures de­signer with basic information on the marine environment and its effects on port design and construction (Chapter 1); port elements and their effects on port operation (Chapter 2); design loads and their combinations that are commonly used to design waterfront structures (Chapter 3); information on the phenomenon of soil I structure interaction that explains basic principles that affect soil lateral thrust against rigid and flexible soil retaining structures (Chapter 4); design of gravity quay walls, sheet pile bulkheads, and piled marine structures (Chapters 5, 6 and 7); basic principles of design of the offshore marine terminals (Chapter 8); modernization of the existing waterfront structure that makes them usable in mod­ern port operations (Chapter 9); and design and construction of breakwaters (Chapter 10).

In both books each chapter includes a comprehensive list of relevant cross-refer­ences intended to help the interested reader to study the subject in additional depth.

In this book I have attempted to provide the reader with a clear understanding of the phenomenon of interaction between the environmental agents such as waves, cur­rents, and wind as well as harbor soils and backfill materials with bottom-fixed marine structures.

During my long career as a practicing waterfront consultant and port engineer considerable progress has occurred in the field of design and construction of port- and navigation-related marine structures. Progress in port design, and in particular design of waterfront structures, has been strongly influenced by the dramatic changes in vessel sizes and in modes of modern terminal operation. Multipurpose ports have been replaced by more specialized termi­nals, which result in dramatic effects on both the design of berth structures and lay­out of the terminal. Furthermore, marine structures for various purposes have been developed using new design and construe-

tion principles, and operation of these structures have been significantly improved by the introduction of new and better fend­ering systems and efficient mooring acces­sories. New and better structural materials have also been introduced. For example, modern concrete technology now enables the engineer to use durable high-strength con­crete, highly resistant to deterioration in harsh marine environments. New and bet­ter repair procedures and rehabilitation techniques for port structures have also been introduced.

Progress in development of new marine structures and modernization of existing structures was based on advances in ana­lytical design methods as well as on result of numerous scale-model tests and field in­vestigations conducted all over the world. Today, marine structure design is a unique discipline in the field of civil engineering that is based on the use of highly advanced methods of soil foundation investigation and thorough understanding of the principles of soiljstructure interaction in the marine en­vironment.

Recently sophisticated computational procedures and mathematical models have been developed and used for design of vari­ous marine structures. It must be stressed, however, that in many cases the diverse and complex geology at various port loca­tions results in a wide variety of geotechni­cal environments. Such conditions require a careful approach to selection of structure type and use of the appropriate design method, which should not necessarily be highly sophisticated. It is a misconception that sophisticated computer analysis, with its greater accuracy, will automatically lead to better design. Despite the highly sophis­ticated analytical methods available today, the marine structural designer must be aware that the design is not merely a stress analysis process. Use of computers has not diminished the value of some hand calcula­tions. In fact, many questions about marine structure engineering are still best an-

swered with simple, often empirically based, but practical formulas.

Computers have revolutionized the pro­cess of structural engineering and greatly increased productivity of engineering firms. Computer-aided analyses are of great help when used in the proper context, for exam­ple, when modeling of the structure is cor­rect, the real boundary conditions are taken into account and most of all when the out­put is examined and interpreted by an ex­perienced engineer. However, some critics observed a "rapid deteriorating competency on the part of the engineering community as a consequence of using computers" and found "a serious lack of critical evaluation ability in many of the young engineers ... (which) put an inordinate amount of faith in the computer" (ENR, October 28, 1991).

The worrisome trend in the present de­sign and construction practices is that some inexperienced, however, highly competent in the use of computers, engineers consider themselves "instant experts" ready to ana­lyze and design anything.

The marine structures designer should realize that formulation of the mathemati­cal approach used for structural analysis must be practical and compatible with available engineering data, for example, shearing strength and consolidation charac­teristics of the foundation and backfill soils, environmental and live loads, etc. However, sometimes even when analytically correct results are obtained, the inexperienced en­gineer can make errors by neglecting some practical aspects related to constructibility, for example, how to fabricate or how to get the structural component in place.

To avoid the disastrous consequences of such designs experienced engineers must spend sufficient time helping their less ex­perienced colleagues to prepare the mathe­matical models and review the computer output.

The 1980s and 1990s have become known for global modernization of existing ports and construction of new high capacity spe-

Preface xxi

cialized marine terminals. During the same period of time the nature of port traffic has changed markedly rendering some older fa­cilities unsuitable for today's operations.

The obvious example is the emphatic shift to containerization of literally all types of cargoes and transportation of containerized goods in ever larger vessels. Similar devel­opments have occurred in transporting of huge volumes of liquid and dry bulk com­modities; sizes of the vessels that now transport these cargoes reached 500,000 DWT and more. Obviously, these giant ves­sels require deeper approach channels; larger harbor basins; deep water quays; gantry cranes with greater height clear­ance, outreach, and lifting capacity; special­ized terminals with appropriate handling equipment; and so on. This gives obvious impetus to global modernization of existing ports as well as to construction of new ports and terminals that can accommodate the modern maritime traffic.

Large capital investments into ports de­velopment have been made in 1960s through 1980s and many experts predict that this trend will continue through 1990s and far beyond into the 21st century.

Much of the capital spent on port devel­opment is allocated for construction, opera­tion, and maintenance of its marine facili­ties. Therefore, economical design of these facilities can save a lot of money needed for port development.

Successful design of any project is based on three pillars; they are

• intelligence • education • experience.

The latter two assume thorough knowledge of a subject matter and the most recent developments in the area of interest. Unfor­tunately, all too frequently good and less costly engineering solutions are not used because of the lack of familiarity on a part of the designer. On the other hand, use of a

xxii Preface

"text book" solution to solve the problem may also be counterproductive.

The subject of marine engineering is a field where ingenuity can achieve consider­able savings. Every project is site specific and therefore no engineer should be content merely to follow anothers designs but should study such designs and use them as a start­ing point for developing his or her own ideas that are best suitable for the particu­lar site conditions.

AB noted earlier the science and practice of port and harbor engineering draw from various disciplines and cover a broad area of interrelated subjects. This book offers ba­sically geotechnical and structural aspects of port and harbor engineering, and no at­tempt has been made to include all detailed analytical procedures from these interre­lated disciplines, for example, dredging, port operation and maintenance, etc. However, where relevant, all efforts have been made to provide the reader with a considerable cross-reference on the interrelated subjects; this includes the most recently published books, papers from the journals of profes­sional engineering societies, and the pro­ceedings of specialty conferences.

The design procedures and guidelines contained in this book are intended to point out the complexity of the particular prob­lem and illustrate factors that should be considered and included in an appropriate design scenario. They should not be used indiscriminately and particularly not for the detailed design, and should always be com­bined with good engineering judgment. As noted earlier, this work has been conceived as a two-part treatise in which I have at­tempted to provide marine structures de­signers with state-of-the-art information and common sense guidelines to the design of basic types of marine structures associ­ated with port activities.

This book is designed to serve as both a guide and a reference for practicing marine and geotechnical engineers and a text for graduate students and others seeking to enter the field of marine engineering.

This book has been 7 years in prepara­tion. I have drawn from more than 40 years of my own experience as a marine engineer and scientist involved with research and all practical aspects of structural design, con­struction, and project management. Also, worldwide experience has been examined and the best of it is included in this work. Subsequently, acknowledgments of mate­rial used in this book are given in the ap­propriate places in the text and figures. I wish to extend my deepest gratitude to all the publishers, authors, and organizations from whom material for this work has been drawn.

This volume is not a one-man job. I am deeply indebted to many experienced indi­viduals who have contributed material and comments to this project. In attempting to make this work most helpful and useful I have drawn from sources including the knowledge and experience of my former col­leagues at Acres International Limited, who assisted in a variety of ways: Dr. W. S. Dunbar contributed information on seismic-induced loads, potentials for soil liquefaction, soil dynamic loads upon re­taining structures, design of a soil retaining structures for seismic loading and also re­viewed several chapters and helped in edit­ing the book; Mr. R. G. Tanner has reviewed several chapters and offered useful com­ments; special gratitude goes to Mr. D. Pro­tulipac who dedicated a great deal of his time to editing most of the text.

I wish to extend my gratitude and ac­knowledge a stimulating and enjoyable col­laboration with: Mr. M. Shiono, Deputy General Manager-Research and Develop­ment, Sumitonio Rubber Industries, Kobe, Japan who contributed information on rub­ber fender systems; Dr. S. Takahashi, Chief of Maritime Structures Laboratory, Port and Harbour Research Institute, Yokosuka, Japan, who contributed Chapter 10 "Breakwater Design"; Dr. M. Gurinsky, Pro­ject Engineer for Hardesty & Hanover Con­sulting Engineers, New York, N.Y., who contributed Section 6.8, "Sheet Pile Bulk-

heads Built Upon Creep Soils"; Mr. D. Weinreb and Mr. P. Wu, both vice presi­dents for Reinforced Earth Company, Ltd., Rexdale, Ontario, who contributed Section 5.10, "Reinforced Earth Quay Walls.

I extend my deepest gratitude to my good friend Roman Glusman for his invaluable help with preparation of some illustrations and Ms. L. Dunn, who typed the manuscript and dealt ably with many difficulties in the process. I wish to thank Sumitomo Rubber Industries, Ltd. for sponsorship of this pro-

Preface xxiii

ject and extend my deepest gratitude to Mr. M. Shiono and Mr. Ed Patrick of Sumitomo Canada for their support. I also wish to thank my publisher, Chapman & Hall, for full cooperation.

Finally, special thanks are due to my wife Nora, for her valuable assistance dur­ing preparation of the manuscript copy, but most important, for patiently tolerating me during the preparation of both volumes.

GREGORY P. TSINKER

Introduction

Ports- Their Past. Present. and Future

Maritime transportation has generally been the most convenient and least expensive means of transporting goods, and this is why mankind, since ancient times, has been steadily extending its activities into this area.

The history of maritime transportation and port development dates back to the year 3500 B.C. and beyond. Over centuries, transport of goods by means of water trans­portation has been evolved in steps with the needs of world trade and technical capabili­ties to build larger ships and ship I cargo handling facilities.

Initially, waterborne traffic has existed on a local basis where small ships sailed out of river ports for other nearby river ports located in the same river system. With ad­vancing navigational skills the merchants ventured greater and greater distances. Thus, larger ships transporting larger quantities of goods have emerged. As ship

traffic increased, the existing river ports became overcrowded, and in order to permit more ships to berth and at the same time to keep the river usable for more ships, piers had to be constructed along river banks.

This stage may be seen as the beginning of the development of modern ports. The ever-increasing demand for shipping and port facilities resulted in construction of the first open-sea ports. Four to five thousand years ago the Phoenicians established open­sea ports along the Mediterranean coast­line, and the Romans built the famous naval port near Rome on the Tiber River at Ostia. By the end of the first century A.D. a num­ber of large ports had been constructed in the Mediterranean, the Red Sea, and the Persian Gulf.

Unfortunately, many of these old ports and harbors have disappeared, either being destroyed during the wars, buried by earth­quakes, or just through neglect and deca-

XXV

xxvi Ports-Their Past, Present, and Future

dence. Some of these ports are known from old documents and others have been discov­ered by archaeologists. As pointed out by DuPlat Taylor (1949), these ports have been well planned and effectively executed.

The description of different methods of port construction in earlier centuries, specifically in the Roman Empire, that in­clude the use of tongue and grooved, lami­nated, and various other types of sheet pil­ing, and large stone blocks are found in treaties by Roman architects (Leimdorfer, 1979).

As ship navigators developed more skill and fears of unknown waters gradually dis­appeared, merchant mariners, in addition to trade between river ports on their own coasts, started sailing the high seas, bring­ing goods from country to country and from continent to continent. The interchange of goods and later of raw materials between countries and continents reached by mar­itime traffic as well as the development of powerful navy fleets brought about develop­ment of large sea ports; this subsequently gave birth to large cities built around these ports.

Many modern cities have been built and expanded around medieval ports located on the open sea, bays, estuaries, sounds, and rivers. Examples are London, Rotterdam, Hamburg, and many others. However, it was not until the 1880s that a revival of interest in port works reappeared.

Port developments and their evolution has started, motivated by both economic and technological pressures that resulted from the global industrial revolution. At this time, the size, diversity, and complexity of ports changed dramatically. To a great ex­tent this have been influenced by the changing nature of ships, for example, the transition from ships made from wood to steel and the introduction and rapid devel­opment of steamboats, and by the demand that greater volumes of cargo be handled at ports more rapidly. The latter stimulated the development of more and more efficient

methods and technologies for handling and hauling of miscellaneous cargoes. However, in the 1880s many kinds of cargos were still handled manually as it had been for cen­turies. Cargoes that consisted basically of bags, bales, bundles, barrels, cases, cartons, drums, pieces of timber, steel, and so forth have been moved manually in the ship, on the quay, in the shed, and in the ware­house, sometimes ''humped" on the back. This created a heavy demand for labor which fluctuated greatly with the arrival and departure of ships. Thus, if the ships were to be turned round efficiently and eco­nomically, a big pool of casual laborers was necessary.

In the late 1880s, ships still continued their transition from sail to steam engine. The capacity of these vessels was a few thousand tonnes and their draft less than 6 m. As ships changed, so did the ports that served them.

In many ports, the finger pier was the most characteristic type of berth construc­tion. Typically, goods were stored there in warehouses located in close proximity to the berth line and were taken in and out of port by horse and cart.

The shift to mechanized handling of car­goes in ports began in the early 1900s. This was largely dictated by the growing volume of maritime traffic and changing size of ships. By the 1920s most of the general cargo ships were using onboard booms to move cargo by the sling-load method. The trend toward the growth of ship size coin­cided with construction of vessels special­ized in transporting a certain type of cargo (e.g., general purpose commodities, dry and liquid bulk cargoes, and others). Naturally, new developments in a ship industry in­evitably brought about innovations in cargo handling and hauling technologies, the most radical of which was introduction of a quay edge cranes.

World War 11-inspired inventiveness took mechanization of cargo handling one step forward by the introduction offorklift trucks

and pallets that enabled the general-pur­pose cargoes to be moved faster. In postwar years, pallets have been standardized inter­nationally by International Standard Orga­nization (ISO) (1992). The ISO Committee stipulated that the maximum permissible width of road vehicles (then mostly flat and open) must be about 245 em; thus, all stan­dard pallets had one dimension, of which 245 em was a multiple, so that they could be stowed across open vehicles without wasting space. The use of forklift vehicles and pallets was very rapidly developed in industry all over the world, and palletized loads occupied the steadily increasing vol­ume of ship holds. This, however, changed drastically in the not too distant future.

The shift to new technologies occurred in the 1950s with the introduction of container ships built to transport large freight con­tainers.

Containers were soon standardized by ISO internationally to 20 or 40 ft in length (6.06 m or 12.19 m) with the outside width and height being 8 ft (2.44 m). At the pres­ent time, the empty weight of a modern 20-ft container ranges from 19 to 22 kN with maximum permitted total weight of 240 kN. The empty weight of a 40-ft con­tainer ranges from 28 to 36 kN with a maximum permitted total weight of305 kN.

Initially, containers have been handled by conventional quay edge cranes. The first specially designed container crane was in­troduced in 1959, and over the last 30 years, container handling cranes have grown. in size and handling capacity. The need for efficient handling of containers stimulated the development of new equipment, such as straddle carriers, heavy lift forklift trucks, gantry cranes, special tractors, and others. Older forklift trucks used for handling gen­eral cargo and pallets had lifting capacities of 30-80 kN. In contrast, today's new fork­lifts for container handling have capacities up to 450 kN.

During the last 25 years, the roll-onjroll­offmethod of handling containers have been

Ports-Their Past, Present, and Future xxvii

developed and used extensively. This method allows containers, but also cars, tracks, trains, and so forth, to roll on ships via large stern or side ramps.

The advent of containers completely overshadowed cargo handling on pallets. The introduction of container systems for transporting goods revolutionized sea and land transport and cargo handling methods; ship turnaround time was reduced spectac­ularly and speed, efficiency, and safety of handling all types of containerized cargoes increased dramatically. This new technol­ogy drastically changed the approach to port planning. In most ports, a previously very effective pier system was disused as general cargo operations have been moved to the usually remote, high-volume container fa­cilities with their large paved container storage areas and relatively few berths. These modern specialized ports and termi­nals tie directly into upland staging areas (marshalling yards) with multimodal links to several cities, a region, or the entire country.

Traditionally, ports have been developed in natural habors and, as mentioned ear­lier, have formed the nuclei for many cities. Today, ports and marine terminals are built wherever they can be economically justified. The need for large open areas to accommo­date a modern container facility has in­duced ports to move to the periphery of cities and often on poor quality land. The latter usually presents a challenge to port designers and has been an area of major controversy related mostly to dredging and disposal of the contaminated dredged soils. Alternatives to dredging have been found in constructing offshore island ports and mov­ing the up-river shallow draft ports down river, to deeper waters.

Dramatic changes have also occurred in the handling of liquid and dry bulk cargoes. Movements of liquid bulk petroleum prod­ucts by ship started in the 1880s when special tanks were mounted onto existing vessels. Prior to this, the only means of

xxviii Ports-Their Past, Present, and Future

moving liquids was in barrels, which was not a very efficient way of transporting ever-increasing quantities as mankind moved into the petroleum age.

Since the introduction of the first tank­mounted vessels, the procedure and method of liquid bulk handling has not changed in principle 100 years later; however, techni­cal improvements in this area have been spectacular. The capacity of liquid bulk car­riers (tankers) in the 1940s has reached 22,000 DWT and at the present time 500,000-DWT tankers ply the oceans. To­day, several shipyards in Europe and Asia have the capacity to build 1,000,000-DWT tankers.

Similar developments have occurred in the transportation of dry bulk materials. Bulk carriers have lagged but tracked tanker growth, and, similarly, tankers may also be expected to grow in the future. The use oflarge and very large deep draft ships for transporting liquid and dry bulk materi­als and the material hauling innovations have changed the nature of the modern port. Ports actually become a highly special­ized terminals able to handle the one spe­cific cargo at very high rates; for example, loading of up to 20,000 tonnesjh and more of dry bulk, and 220,000 m3 of crude oil per day; thus, annual throughput of tens of mil­lions of tonnes has been achieved.

Deep draft vessels need deep water ports. It has been learned, however, that the con­ventional approach to construction of such ports, involving dredging of large quantities of sometimes contaminated sediments, can be prohibitively expensive. The solution has been found in the construction of offshore marine facilities not protected from the ef­fects of environmental forces such as waves and currents. At these facilities, the low berth occupancy due to rough sea condi­tions has been compensated for by a very high rate of material handling on calm days. These facilities have been constructed far enough offshore where sufficiently deep wa­ter is found and no maintenance dredging is

needed. In some instances the terminals have been moved as far as 2 km or more offshore and have been linked to the shore either by a bridgelike trestle, designed to support pipe lines or conveyor systems and to provide access to the terminal for lightweight vehicular traffic or by subma­rine pipelines. In some instances, particu­larly in heavily populated areas where local residents object to the construction of con­ventional trestles as an unacceptable "vis­ual pollution," submarine tunnels have been constructed as a solution to the problem.

The modern port is developed as an im­portant link in a total transportation sys­tem and planners of such multimodal sys­tems seek to optimize the total network, not just one of its components.

Construction of a new port, or expansion or modernization of an existing one, is usu­ally carried out to increase port capacity and its effectiveness. Traditionally, this has been focused on the sea, and, consequently, construction of new berths and moderniza­tion and expansion of existing ones was the prime area of interest. However, as urban coastal areas, particularly in developed countries, have substantially expanded over the last five decades, while concurrently in­ternational trade has increased and con­tinue to expand, making the world more and more economically interdependent, the port land-side capacity to transfer the cargo from the wharf to the end user has become increasingly critical. In some densely popu­lated areas, the available transportation network (e.g., highway and rail) is limited to moving a certain amount of cargo and cannot be expanded further. Under these conditions there is no logic in increasing the existing port capacity, unless the land-side transportation infrastructure is equally ca­pable of moving the increased volume of cargo through the land-based transporta­tion network.

In this respect, to avoid a waterfront con­flict, many countries have developed a mas­ter plan for its major ports. For example, in

Canada, both the Canada Ports Corporation (a Canadian Crown Corporation) and indi­vidual ports have developed land use plans and economic impact assessment in cooper­ation with the cities and local special-inter­est groups which interface with port activi­ties (Gaudreault, 1989).

In the view of many experts, moderniza­tion of existing ports will continue and many new ports will be developed in the 1990s and beyond due to major expansion of the world economy. The latter is result of dra­matic growth of the world population, gen­eral industrial growth, and growth of petroleum and mineral material industries.

The real value of world trade will con­tinue to grow. The new North American Free Trade Agreement (NAFTA) between the United States, Canada, and Mexico and new improved GATT treaty arrangements are expected to encourage similar agree­ments elsewhere in the world that will eventually result in the total world market free from protectionism and · immune to destabilizing political upheaval in some re­gions. As pointed out by Barker (1990/1991) in future trade,

. . . the exporters will seek to increase the added value of their trade, which will tend to reduce tonnages of raw commodities and in­crease those in partially or fully processed materials. Thus increasingly refined petroleum products, chemicals, alumina or aluminum ingots or aluminum products, steel products, vehicles, sawn and processed tim­ber products, processed agricultural commodi­ties and such-like will be the cargoes rather than the basic raw commodities. These are more valuable and readily damaged cargoes which require more careful handling and stor­age. The trend to more specialized vessels such as reefer, parcel tanker, car carriers and roll-onjroll-off will continue and many of the processed cargoes will end up being handled in containers.

This trend is already quite visible in Asia. For example, today, Thailand's exports con-

Ports-Their Past, Present, and Future xxix

sist of 75% manufactured goods as opposed to export of raw materials and this trend is characteristic of most countries in South East Asia. Wider, nonstandard container are already the reality, and the trend for use of larger containers will continue. New container sizes will inevitably have great impact on the design of new containerships and the container handling technologies.

The most radical and far-reaching changes in container terminal technology will be their continuing automation which will lower manpower requirements and op­erating costs, increase control, and speed the flow of goods through the ports. Future terminals will be more flexible and easily adaptable to changes in the world's econ­omy resulting in cyclic changes in demands.

Alternatives to dredging and construc­tion of deep water ports will be design of wider vessels with lesser drafts. The impor­tant new development in port operations that occur about three decades ago was the virtual disappearance of the true passenger liners; the cruise industry has emerged to replace it. Today, the passenger trade exists basically on local lines on inland waterways and between coastal ports .

Cruise vessels, to date, have continued to look like liner vessels, notwithstanding that speed is no longer of paramount impor­tance. Cushing (1989) predicts that cruise vessels will change; they will become larger, slower moving floating resorts.

The new ideas in port operations will bring new engineering and construction ideas in their wake. As pointed out by Hochstein (1992), the nontechnical aspects of port performance, such as commercializa­tion, liberalization, and privatization, along with improvements of port administration will continue to contribute to the institu­tional restructuring and drastic improve­ments in port operations.

Commercialization gives to the port au­thorities freedom similar to the private sec­tor where decision making is decentralized

xxx Ports-Their Past, Present, and Future

and management is held accountable for port performance.

Liberalization lessens the port authori­ties' monopoly on power by allowing the private sector to provide similar services and is complementary to commercialization.

Privatization transfers functions previ­ously performed by the port authority (government) to private sector. It may in­volve transfer of full or partial ownership of port facilities, or it may be limited to pri­vate sector management practices for the provision of port services via lease and op­erating contracts. Privatization usually as­sociates with eliminated subsidies and re­duced costs of port operation.

The privatization of ports brings greatly enhanced commercial freedom to port man­agers and is recognized as one way to react more positively to market opportunities and use human incentives, based on personal . gains and improvements, to increase effi­ciency of the port operations. This trend is natural and will continue both in developed and developing countries.

It must be recognized, however, that ports and harbors are built and operate within a certain societal framework that includes an array of political, financial, en­vironmental, and other considerations. Therefore, the port planner must have a clear understanding of local technical and nontechnical issues. For example, in some developing countries, existing or new ports are not solely an industrial development but also enterprises aimed at solving some regional, social, or demographical problems. Therefore, a careful approach to port priva­tization is needed in developing countries. The latter assumes that although commer­cial spirit there must not be discouraged, the commercial approach to port operations in some developing countries should not pursue a short-term financial gain.

In Europe, port privatization has been successfully introduced in the 1980s in the United Kingdom where it is likely to accel-

erate in the 1990s. Also, today it is most apparent in Asia.

Improvement of port administration en­compasses actions that improve the perfor­mance of the organization. It may include corporate planning and carrier develop­ment, as well as installation and constant modernization of a computerized manage­ment information systems that enhances management without changing the port's institutional structure.

Recent experience in ports worldwide suggest that commercialization and privati­zation are the most far-reaching and effec­tive strategies to achieve the objective of port effectiveness.

In conclusion to this section it should be noted that the future is not possible with­out thorough familiarity with the past which is a true foundation for new ideas. As Tooth (1989) rightfully said, "The past is not just something out of date, it is a record of human experience-an experience is cer­tainly something which should be used to help shape the future."

For more information on port develop­ments the reader is referred to Dally (1981), Cushing (1989), Clearwater (1992), Thom­son (1992), and PIANC (1987, 1989, 1990).

Engineering Advancement in Port Design and construction

The primary construction materials that were used for construction of older marine facilities were wood and stone. They were worked by hand and used for construction of sheet-pile bulkheads, piled piers, quay walls, breakwaters, and other structures. Wooden sheet piles and regular piles were driven by using primitive power equipment, and stone was placed from crude construc­tion platforms.

More than five centuries ago the Phoeni­cians extensively used wooden sheet piles and piles for construction of their marine facilities. For sheet-piling they used long planks made from Lebanon cedar. Various

types of timber sheet-piling techniques (e.g., tongue and groove, laminated, and others) were used. These piles were driven succes­sively edge to edge to form a vertical wall for the purpose of preventing the retained materials from spreading and from being undermined by the action of waves and cur­rent. This type of construction was also known to ancient Egyptians and Romans. The Phoenicians also used heavy blocks locked together with copper dowels for con­struction of the open-sea port at Tyre. This type of construction was also used by the Romans. In the 1800s, both materials still played a major role in port construction.

A great variety of gravity-type walls con­structed from rubble masonry or heavy granite or limestone blocks have been built during the 1880s. The history of heavy blockwork construction is traced back to ports in Mediterranean, at Marseilles and Algiers, with much of this pioneering work being carried out at the Port-of-Bonqie, Al­geria where a quay wall composed C!f lime­stone blocks had been built as far back as 1840. During the same period of time, wood was extensively used for the construction of piled wharves and piers, as well as for grav­ity-type quays comprised of floated-in tim­ber cribs with or without a masonry super­structure.

It should be noted that improved and economically sound blockwork quay walls are still in use. Details are provided in Chapter 5. Today, timber cribs are used where wood is in abundance, and timber sheet-pile bulkheads made from treated wood have been constructed elsewhere, par­ticularly in coastal regions as a secondary line of shore defense in ocean-exposed loca­tions and for construction of low-height ma­rine structures in small-craft harbors. Well-treated timber sheeting is also em­ployed in permanent structures where it is always hidden under water, thus preserved from rot, and at locations where there is no marine organisms (e.g., borers) which can

Ports-Their Past, Present, and Future :xxxi

destroy wood. The same is true for wooden piles.

Cast-iron piles became complementary to timber piling in the early 1800s (Borthwick, 1936). The earliest reported use of iron sheet piles was construction of the North Pier of Bridlington harbor, the United Kingdom, in the early 1820s (Mackley, 1977). Various types of iron sheet-pile sections were avail­able at that time, and a considerable amount of exploratory work was carried out in order to develop the most economical profile. Cast iron, however, as a material had limitations primarily because of its vul­nerability to brittle fracture during driving in hard soils. Typically, wrought-iron piles were used in a composite riveted form and were based primarily on the fitting of plates between suitable guides or against sup­ports.

In 1897 a Danish engineer, Larssen, rev­olutionized the use of iron sheet piles by introducing a new pile section which was developed from a rolled trough section plus a riveted "z" section, to form an interlock; this shape is very familiar in modern con­struction.

In 1914 Larssen also introduced the first deep-arch section in which interlocks were situated in the neutral axis of the complete section; thus, their material bulk did not influence the bending moment to be taken up.

Larssen's inventions and modifications helped to greatly increase the capacity and effectiveness of sheet piles in their ability to resist earth and water pressures. Increased pile stiffness enabled it to be driven without buckling or springing under the blows of the driving hammer, increased water-tight­ness of the sheeting prevented seepage through the wall, and, most importantly, efficient use of rolling mills produced an economical section with interlocks.

At the beginning of this century, both wood and iron have been replaced by steel and reinforced concrete. The first sheet pile

xxxii Ports-Their Past, Present, and Future

ever made from a rolled section was used in Chicago in 1901; it was called the Jackson pile. This was followed by the rather fast development of numerous straight or trough sections of steel piles that were produced around the world, either with integral lock­ing arrangements or with a separate inter­locking member.

The first steel "z"-shaped sheet piling known as the Hoesch system was intro­duced in Belgium in 1913. In comparison with other sections, this type of piling was stiffer and had a higher section modulus at equal weight with other piling systems. Since this time, various combinations of different piling systems and various types of box piles (H-section) have been intro­duced in North America and Europe. At present, a variety of high-strength sheet­pile sections are available from different pile manufacturers.

In addition to the above-mentioned piles, relatively low sectional modulus straight web steel sheet piles are often used in ma­rine application for construction of cellular-type bulkheads. These piles were first manufactured and used in the United States in 1908/1909.

It should be noted that steel pipe-type sheet piles are now coming into widespread use for deep water construction where a sheeting of greater strength is required.

Reinforced concrete sheet piles have been used in harbor construction since the begin­ning of this century. They are usually con­sidered relatively maintenance-free compo­nents of a sheet-pile wall. Although many different design types have been developed and used in the past 50 or so years, the straight web piling bar provided with a tongue and groove, similar to that used on timber piles, is the most commonly used. Since the 1950s, prestressed concrete sheet piles have replaced almost completely the ones made from regular reinforced concrete.

Prestressing of concrete sheet-pile rein­forcement has an advantage, especially in seawater environment, as cracking of con-

crete in the tension zone is thereby largely eliminated and the danger of corrosion of reinforcement is decreased.

The same applies to regular concrete piles that are extensively used in marine applica­tion. The advantage of piled structures is that they enable practically free passage of waves, which makes them particularly at­tractive for construction of the deep water offshore terminals.

A great variety of concrete and steel piles have been developed and used from the beginning of this century. The wide variety of these piles is discussed in Chapter 7.

The most significant development in this area is the use of large-diameter (up to 3.0 m and more), very long (60 m and longer) prestressed concrete and steel cylindrical piles. Depending on geotechnical site condi­tions, these piles can be installed by differ­ent methods (e.g., driven by hammer, vibra­tor, hydraulically, or a combination of some of these). It should be pointed out that the vibratory hammers introduced in the fifties and sixties changed the basic way piles had been driven since the late 1800s. New hy­draulically operated hammers enable the constructors to drive piles under water. Similarly, very large floating and jack-up pile-driving equipment was developed and used for pile installation at exposed off­shore locations. An array of piles with en­hanced bearing capacities have been devel­oped; for example, screw piles of different designs, prefabricated piles with enlarge­ments on their shafts, belled piles, and other have been s~ccessfully used in port and offshore construction.

High-strength steel and prestressed con­crete allow the port designers and construc­tors the flexibility to design for greater depth, longer spans and higher capacity. For example, general cargo wharves are now routinely designed for 5.0 tonnesjm2, up from 2.0 tonnesjm2 60-70 years ago.

Galvanization and the use of protective coatings, such as epoxy, which came into use in the 1950s increased the longevity of

marine structures. Epoxies are also used by constructors for splicing concrete structural elements in the field.

Remarkable progress has been achieved in concrete technology. Today's structural concrete is indeed a mixture of admixtures. Products such as superplasticizers, re­tarders, accelerators, air entrainers, and others allow concrete pours in cold temper­ature or hot weather. A denser and higher quality product is obtained by use of silica fume in a slurry or powdered form. Silica fume can substantially increase strength and density of concrete and make it virtu­ally impervious to chloride penetration in the harsh marine environment. Further­more, use of corrosion inhibitors may slow down the potential onset of corrosion in steel reinforcing bars.

Development of huge floating heavy lift equipment revolutionized the construction of gravity-type quay walls and breakwaters. These structures, generally built in water depths of 6-9 m in the late 1800s, are now constructed at depths of 25 m and below.

Finally, it should be pointed out that in the past 30-40 years primitive fenders used for protection of marine structures from ship impact have been replaced by very efficient high-energy-absorbing and low-reaction­force rubber fender systems. At the present time, fender units are manufactured from solid a,nd laminated rubber in different shapes and sizes. They are also manufac­tured in the form of a low-pressure inflated balloon (pneumatic fenders), or as a closed­cell foam filled unit. The pneumatic fender units have been manufactured up to 4.0 m in diameter and 12.0 m long.

In modern marine engineering practice, a number of innovative and economical gravity-type quay walls have been em­ployed. Among them are concrete large­diameter floated-in caissons, bottomless concrete cylinders, and prefabricated L­shaped retaining walls of miscellaneous de­signs.

Ports-Their Past, Present, and Future xxxiii

An economical solution to gravity wall construction in the wet was also achieved by use of the traditional structures such as a large-diameter steel sheet-pile cell, a con­ventional boxlike floated-in concrete cais­son, and blockwork walls of enhanced de­signs.

The economy of gravity wall construction was significantly improved by using innova­tive methods of bed preparation and place­ment and densification of backfill materials. Detailed information on this subject is given in Chapter 5.

Waterfront construction was accelerated by the use of prefabricated structural com­ponents. Prefabrication dramatically re­duced the time required for overwater con­struction and enhanced quality and there­fore longevity of marine structures.

The design of any project is a continuous process, which begins with the perception of a need or opportunity, followed by a feasi­bility study that usually includes a concep­tual design, and embedded by the detail design. The latter is followed by the con­struction of the project with subsequent commissioning. Furthermore, where re­quired to support the basic concept of the project (e.g., harbor layout) or permit inno­vative structural designs to be used with confidence, research is undertaken.

In the past, port and its related marine structures have been designed with a high degree of redundancy, largely because of the relatively rapid deterioration rate of structural materials in the marine environ­ment, but also due to a lack of proper understanding of wave mechanics, mecha­nisms of ship-structure andjor soil-struc­ture interaction. The latter was particularly true in designing a "flexible" structure such as sheet-pile bulkheads.

In the past 50 years, substantial progress has been achieved in such areas as the development of new, much stronger and more durable structural materials, the in­troduction of better construction tech­nology, and a better understanding of the

xxxiv Ports-Their Past, Present, and Future

process of soil-structure interaction. Thus, research and development directly or indi­rectly became the integral part of the de­sign process.

The design of port layout with its related structures such as breakwaters, piers, and quay walls normally involves a great num­ber of parameters that are generally consid­ered to be far beyond the ability of purely analytical methods to achieve the reliable solution. This has been overcome by use of large-scale physical models, which appear to be a viable tool in solving a complex multiparameter problem.

Today's engineers have abundant analyt­ical capability supported by computers. The mathematical modeling of a complex phe­nomenon such as the interaction between nature and engineering developments has become commonplace in the design process. It enables the engineer to .closely predict the behavior of the complex structure in practice.

For complex projects, both mathematical and physical models are best used in combi­nation. However, despite the prediction of model studies, the designer should exercise the proper level of conservative engineering judgment which is dictated by the complex­ity of marine foundations, marine environ­ment, ship maneuvers, and so forth.

Today, port and harbor engineering has entered the electronic age. The computer vastly enhances an engineer's productivity and his or her opportunities for innovative design. In addition to reducing the opportu­nities for making errors, the use of comput­ers drastically enhances engineering judg­ment. By taking advantage of the speed of computer analysis, the engineer can explore a number of design alternatives in a short period of time. Today, computer hardware and software allow the engineer to see his project from all perspectives, investigate each detail, make changes by shaping as a sculptor might, then, when all is finished, have the calculations and drawings pro­duced. Computer-aided design and drafting

(CAD) open opportunities for transition from traditional two-dimensional (2-D) de­sign to three-dimensional (3-D) design. This has been made feasible by the rapid ad­vances in computer-graphics hardware which now permits full 3-D CAD models to be displayed quickly and effectively, with hidden lines removed or with shading; 3-D computer models can be viewed from any angle and viewpoint, in orthographic, iso­metric, perspective, or cutaway views. This helps to make. the project aesthetically more acceptable to the community and overcome the public resistance to some projects re­garded as a "visual pollution" to the area. The importance of aesthetic aspects of any project now is fully recognized by the de­signers and developers, and the 3-D ap­proach to structural and civil design helps to bridge the gap between art and science.

Unfortunately, computerization of the design process has its own drawbacks; it provides not only the leading edge of tech­nology but have been also a major source of concern. The popularity of computers has resulted in a flood of software, and on today's software market, there are nearly as many computer programs as there are researchers. Unfortunately, the quality of some software presently available on the market is questionable, and it would be of great interest and perhaps shock to some when results of analyses of a certain struc­tures are compared with the same input data using different programs.

The difference in the software output happens because some developers of com­puter software blindly rely solely on the mathematical approach to solving the prob­lem and are ignorant about current state­of-the-art knowledge.

Sometimes problems with software (e.g., incorrect sign convention) may cause a com­puter to subtract stresses when it must be added can be difficult to detect.

Growing reliance on computer-aided analysis and design without adequate con­trols on misuse can lead to structural fail-

ures and, subsequently, to "computer-aided liabilities," the term used by Backman (1993) in her interesting paper on a subject matter.

Recognizing this as a potential problem, the Committee on Practices to Reduce Fail­ures, under the American Society of Civil Engineers Technical Council on Forensic Engineering, is currently preparing a mono­graph titled "Avoiding Failures Caused by Misuse of Civil Engineering Software." The monograph, scheduled for publication in 1996, will examine all computer-related is­sues where misuse could result in cata­strophic failures, poor performance of facili­ties, and poor solutions to problems in civil engineering.

Due to a worsening legal climate for practicing engineers, the designers are of­ten not willing to accept potential risk asso­ciated with a more economical or innovative design. The conservative approach, which limits innovations in design and construc­tion practices, causing economical prob­lems, has been especially visible in founda­tion engineering. This has been explained by the uncertainties in soil-structure inter­action and usually limited information on foundation soils available to the designer. In the past 35-40 years, this has been im­proved by the extensive research into statistics and risk analysis, as applied to the field of geotechnical engineering.

Also, the observational (monitored deci­sions) method, which provides the designer with flexibility in the decision-making pro­cess, has been introduced.

Statistics provide procedures for obtain­ing information from given quantitative measurements, which, in turn, permits analysis of how the aforementioned listed uncertainties of soil and other parameters involved in soil-structure interaction may affect the design of the structure; risk anal­ysis is a set of decision-making procedures dealing with difficult design circumstances, where many components interact such that there is more than one mode of failure; and

Ports-Their Past, Present, and Future xxxv

the observation method is a departure from the traditional design process in geotech­nicaljfoundation engineering, because it allows one to make a final decision on foun­dation design in the future, both during construction when uncertainty in founda­tion soils became understood and during facility operation. The latter is particularly important where long-term changes in soil-structure interaction are expected.

Several advancements in port engineer­ing have been pointed out in this section and the reader will find much more else­where in this book.

Finally, it should be noted that in the past in order to reduce the cost of a design, attempts to standardize construction of ma­rine structures have been made. It has been proved, however, that standard designs to meet various site conditions, in general, and marine facilities, in particular, are not eco­nomical. In general, it is because the cost of the waterfront structure is so high that it would be false economy to attempt to re­duce design costs by limiting the scope of design studies.

In conclusion, it must be said that pro­ducing a good, sound, and effective design is, of course, science; however, it is also an art. Just as an artist does, the designer must be imaginative in developing the con­cept of his or her project and, as a scientist, careful and meticulous in paying attention to all details.

REFERENCES

BACKMAN, L., 1993. "Computer-Aided Liability." ASCE Civil Engineering, June.

BARKER, J., 1990/1991. "Ports in the 1990's and Beyond." The Dock & Harbour Authority, De­cember/January.

BORTHWICK, M.A., 1936. ''Memoir on the Use of Cast Iron in Piling, Particularly at Brunswick Wharf, Blackwall." Transaction Institute Civil Engineers, Vol. 1.

CLEARWATER, J. L., 1992. "Port Construction Since 1885: Evolving to Meet Changing World." The Dock & Harbour Authority, May.

xxxvi Ports-Their Past, Present, and Future

CusHING, C. R., 1989. ''Vessels of the Future: A Naval Architect's Viewpoint." PIANC Bulletin No. 66.

DALLY, H. K, 1981. "The Effect of Development in Cargo Handling on the Design of Terminal Facilities." PIANC Proceedings XX:Vth Congress, Edinburgh.

DuPLAT TAYLOR, F. M., 1949. "The Design, Con­struction and Maintenance of Docks, Wharves and Piers." Eyre & Spottiswoode, Ltd., Lon­don.

GAUDREAULT, R., 1989. "Where Have We Been, Where Are We Going? A Canadian Perspec­tive." Presentation to ASCE Specialty Confer­ence PORTS'89, Boston, Massachusetts.

HocHSTEIN, A., 1992. "Implications of Institu­tional Changes on Port Performance in Asia and Latin America." ASCE Proceedings Spe­cialty Conference PORTS'92, Seattle, Wash­ington.

INTERNATIONAL ORGANIZATION FOR STANDARDIZA­TION (ISO), Standards Handbook, 2nd edition, 1992. Freight Containers, Switzerland.

LEIMDORFER, R., 1979. "La Saga des Palplanches." PIANC Bulletin No. 34, Vol. III.

MACKLEY, F. R., 1977. (Reported by Buckley, P. J. C.) "The History and Development of Sheet Piling." Proceedings Institution of Civil Engi­neers, Part 1, No. 62, February, London.

PERMANENT INTERNATIONAL AsSOCIATION NAVIGA­TION CONGRESSES (PIANC), 1990. Twenty­Seventh PIANC Congress PCDC Panel Dis­cussion, Osaka, Japan.

PERMANENT INTERNATIONAL AsSOCIATION OF NAVI­GATION CONGRESSES (PIANC), 1989. Panel 3: Future Marine Terminal Designs. Five papers on subject matter. PIANC Bulletin No. 67.

PERMANENT INTERNATIONAL AsSOCIATION OF NAVI­GATION CONGRESSES (PIANC), 1987. "Develop­ment of Modem Marine Terminals." Supple­ment to Bulletin No. 56.

THOMSON, B., 1992. "A New Era for British Ports." The Dock & Harbour Authority, June.

TOOTH, E. S., 1989. "A Glimpse of the Past." The Dock & Harbour Authority, May.

contributors

Mr. M. Shiono President SRI Marine Servie Co. Ltd. 1-14, 4 chome Isogami-Dori Chuo-Ku, Kobe 651, Japan

Dr. S. Takahashi Chief Maritime Structures Lab Port and Harbour Research Institute 3-1-1 Nagase Yokosuka, Japan 239

Mr. P. L. Wu, P.E. and Mr. D. Weinreb, P.E. Vice Presidents Reinforced Earth Co. Ltd. 190 Attwell Dr., Suite 501 Rexdale, Ontario, Canada M9W 6H8

Dr. M. Gurinsky, P.E. Project Engineer Hardesty & Hanover Consulting Engineers 1501 Broadway New York, N.Y. 10036

Dr. W. S. Dunbar Engineering Consultant 925 Leovista Ave. North Vancouver, British Columbia, Canada V7R 1R1

xxxvii