Description
Book SynopsisTable of ContentsAbout the Author xi
Preface xiii
Acknowledgments xv
1 Introduction 1
1.1 Scope 1
1.2 Background 2
2 Pole Structures 7
2.1 General 7
2.2 Wood Pole Strength 8
2.3 Loads 13
2.4 Embedment Depth 15
2.5 Guying 17
2.6 Column Buckling 19
2.7 Grounding and Bonding 22
3 Pole Installation and Maintenance 23
3.1 Pole Placement 23
3.2 Guys and Anchors 24
3.3 Pole Maintenance 26
4 Wires, Conductors, and Cables 31
4.1 Categories 31
4.2 Messenger Wire/Strand 31
4.3 Electric Supply (Power) Cables 33
4.4 Communications Cables 35
4.5 Wireless Attachments 38
5 Cable Installation 39
5.1 Conductor and Cable Placement 39
5.2 Lashing Operation 40
5.3 Overlashing 41
6 NESC® Requirements (Strength and Loading) 45
6.1 National Electrical Safety Code (NESC) 45
6.2 Loading Requirements 46
6.3 Strength Requirements 49
6.4 Wire Tensions 52
6.5 Guyed Poles 53
6.6 Extreme Wind Loads (“60 ft Limit”) 54
6.7 Allowable Deterioration 56
6.8 Overlashed Cables 57
6.9 Software Tools and Pole Loading Analysis 60
7 NESC® Requirements (Clearances) 63
7.1 Clearances 63
7.2 Clearance Zones 63
7.3 Clearances Above Surfaces and Buildings 66
7.4 Clearances Between Wires 67
7.5 Overlashed Cables 67
8 Principles of Wire Sag 71
8.1 Catenary 71
8.2 Initial and Final Sag 72
8.3 Sag–Tension Relationship 72
8.4 Determining Change in Sag (and Tension) 73
8.5 Ruling Span 76
8.6 Point Load 77
9 General Order 95 (California) 81
9.1 General Order 95 (GO 95) 81
9.2 Loading Requirements 81
9.3 Strength Requirements 83
9.4 Clearances 84
10 Examples 85
10.1 Purpose 85
10.2 Tangent Line 85
10.3 Line Angle 88
10.4 Line Angle – Buckling Consideration 90
10.5 Additional Attachment 94
10.6 Summary 96
Appendix A Properties of Messenger Strands 99
Appendix B Wireless Attachments 101
Appendix C Extreme Wind and Extreme Ice Loadings 103
Appendix D Solution of Cubic Equation 107
Appendix E Point Load 109
E.1 Parabolic Model 109
E.2 Intersecting Straight Lines Model 111
Glossary 115
References 121
Index 123
