Overhead Distribution Lines: Design and Applications

ISBN-13: 9781119699132 / Angielski / Twarda / 2021 / 144 str.

Lawrence M. Slavin

Spis treści

About the Author xiPreface xiiiAcknowledgments xv1 Introduction 11.1 Scope 11.2 Background 22 Pole Structures 72.1 General 72.2 Wood Pole Strength 82.3 Loads 132.4 Embedment Depth 152.5 Guying 172.6 Column Buckling 192.7 Grounding and Bonding 223 Pole Installation and Maintenance 233.1 Pole Placement 233.2 Guys and Anchors 243.3 Pole Maintenance 264 Wires, Conductors, and Cables 314.1 Categories 314.2 Messenger Wire/Strand 314.3 Electric Supply (Power) Cables 334.4 Communications Cables 354.5 Wireless Attachments 385 Cable Installation 395.1 Conductor and Cable Placement 395.2 Lashing Operation 405.3 Overlashing 416 NESC(r) Requirements (Strength and Loading) 456.1 National Electrical Safety Code (NESC) 456.2 Loading Requirements 466.3 Strength Requirements 496.4 Wire Tensions 526.5 Guyed Poles 536.6 Extreme Wind Loads ("60 ft Limit") 546.7 Allowable Deterioration 566.8 Overlashed Cables 576.9 Software Tools and Pole Loading Analysis 607 NESC(r) Requirements (Clearances) 637.1 Clearances 637.2 Clearance Zones 637.3 Clearances Above Surfaces and Buildings 667.4 Clearances Between Wires 677.5 Overlashed Cables 678 Principles of Wire Sag 718.1 Catenary 718.2 Initial and Final Sag 728.3 Sag-Tension Relationship 728.4 Determining Change in Sag (and Tension) 738.5 Ruling Span 768.6 Point Load 779 General Order 95 (California) 819.1 General Order 95 (GO 95) 819.2 Loading Requirements 819.3 Strength Requirements 839.4 Clearances 8410 Examples 8510.1 Purpose 8510.2 Tangent Line 8510.3 Line Angle 8810.4 Line Angle - Buckling Consideration 9010.5 Additional Attachment 9410.6 Summary 96Appendix A Properties of Messenger Strands 99Appendix B Wireless Attachments 101Appendix C Extreme Wind and Extreme Ice Loadings 103Appendix D Solution of Cubic Equation 107Appendix E Point Load 109E.1 Parabolic Model 109E.2 Intersecting Straight Lines Model 111Glossary 115References 121Index 123

O autorze

Lawrence M. Slavin, PhD, is Principal of Outside Plant Consulting Services, Inc. (OPCS). He represents the nation's telephone industry, via the Alliance for Telecommunications Industry Solutions (ATIS), on several NESC technical subcommittees, as well as the Executive Subcommittee, Main Committee and Interpretations Subcommittee. He also serves on Accredited Standards Committee ASC-O5 for wood products, including ANSI O5.1, Wood Poles, Specifications and Dimensions, and is a member of the ASCE 7 Atmospheric Ice Loads Subcommittee.