Ontario Wood Bridge Reference Guide By Moses Structural Engineers and Brown & Co. Engineering Ltd. for the Canadian Wood Council and the Ontario Ministry of Natural Resources and Forestry CONTACT Ontario Wood WORKS! 1350 Fisher Street, Unit 115 North Bay, ON P1B 2H1 Authors Moses Structural Engineers: David Moses, Mary Alexander, Katherine McAlister, Karen Mesa Brown & Co. Engineering Ltd.: Andrew Lehan, Stephen Brown, and Genaro Dulay Acknowledgements The Canadian Wood Council/Ontario Wood WORKS! wishes to thank the Ontario Ministry of Natural Resources and Forestry, FedNor, Natural Resources Canada, the Province of Québec, and cecobois. Their financial and in-kind contributions made the publication of this document possible. This report was prepared with the technical assistance of Professor Paul Gauvreau, Dr.sc. techn., P.Eng., Professor at the University of Toronto, Department of Civil Engineering. Thank you to the following individuals who provided interviews to the authors: Jasmine Wang, Ph.D., P.Eng. of the Canadian Wood Council, Andrew Lehan, P.Eng., M.A.Sc. of Brown and Company., Marshall Leslie of M.Leslie, Inc., Caroline Frenette, ing. Ph.D. of cecobois, Richard Krutzler of LEA Consulting Ltd., and James Wacker of the US FPL. Thank you to the following individuals who peer reviewed the document: Jasmine Wang, Ph.D., P.Eng. of the Canadian Wood Council and Caroline Frenette, ing. Ph.D. of cecobois. Thank you to the following individuals who peer reviewed the design examples: Tyler McQuaker, P.Eng., Sr. Structural Engineer from NWR Structural Section/Ministry of Transportation Ontario, Cory Zurell, PhD, P.Eng., Principal from Blackwell Structural Engineers and François Pelletier, ing, Direction générale des structures from Ministère des Transports, de la Mobilité durable et de l’Électrification des transports. Thank you to the following individuals who supplied reference material for the document: Patrick Crabbe from Atlantic WoodWORKS!, Percy Champagne from FPInnovations, John Pineau from FPInnovations, Mohammad Mohammad from FPInnovations and NRCan, Dan Tingley from TRS/WRD, Gary Farnden from Government of BC, Ministry of Transportation and Infrastructure, Terry MacKay from Government of BC, Ministry of Transportation and Infrastructure, Brian Chow from Government of BC, Ministry of Transportation and Infrastructure, Keven Durand from Nordic Structures and Crawford Dewar from Guardian Bridge Rapid Construction. Copyright © 2017 Copyright notice: With the permission of Canadian Standards Association, (operating as “CSA Group”), 178 Rexdale Blvd., Toronto, ON, M9W 1R3, material is reproduced from CSA Group’s standard S6-14 – Canadian Highway Bridge Design Code. This material is not the complete and official position of CSA Group on the referenced subject, which is represented solely by the Standard in its entirety. While use of the material has been authorized, CSA Group is not responsible for the manner in which the data is presented, nor for any representations and interpretations. No further reproduction is permitted. For more information or to purchase standard(s) from CSA Group, please visit http://shop.csa.ca/ or call 1-800-463-6727. Disclaimer: It is intended that this guide is to be used in conjunction with competent engineering design. The authors, Moses Structural Engineers Inc., Brown & Co. Engineering Ltd., Ontario Wood WORKS!, the Canadian Wood Council, the Ministry of Natural Resources and Forestry and their contractors make no warranty, expressed or implied, or assume any legal liability or responsibility for the use, application of and/or reference to the information included in this publication and/or omissions in this work, or for any engineering designs, plans, or construction prepared from it. Consult your local jurisdiction or design professional to assure compliance with code, construction, and performance requirements. This guide does not exempt applicants from obtaining any other authorization(s) required by any law or regulation, as the case may be. Photo credit for cover: Stephane Groleau Ontario Wood Bridge Reference Guide i FORWARD Timber bridges have a long history of construction and use throughout North America, including Ontario, for roadways, railways and logging roads. The Canadian Highway Bridge Design Code (CHBDC), together with the Canadian Wood Council publication Wood Highway Bridges from 1992 are typically referenced by designers of timber bridges in Ontario. This new reference is intended to provide updated background information for designers as they embark on proposing and designing timber highway bridges for primary and secondary roads. This reference is divided into three parts: Part 1 – Wood Bridges – Design and Use Part 2 – Opportunities & Current Limitations Part 3 – Design Examples Part 1 provides background information on topics including wood materials, bridge systems, prefabrication, durability and species availability. Details of costs, construction cycle and sustainability are also provided. Part 1 concludes with examples of a variety of completed highway bridges from North America and Europe. Part 2 of this reference is intended to provide designers and authorities with highlights of the current edition of the CHBDC on subjects related to the wood highway bridges, including areas that will require future development in the code. Additional references to other resources for advancing practitioner knowledge of and advancing the state of the art in wood bridge design are provided. Part 3 has two fully worked design examples of a two-lane 18-m span wood highway bridge designed in accordance with the latest provisions of the CHBDC and the best available information from current literature. Each example is based on a single-span, simply-supported glued-laminated girder bridge. One bridge has a glued-laminated deck and the other has a stress-laminated deck. These examples are intended to help designers understand the key issues as they undertake wood highway bridge design. Durability through detailing and choice of materials is discussed. ii Ontario Wood Bridge Reference Guide TABLE OF CONTENTS PART ONE – WOOD BRIDGES PART TWO – OPPORTUNITIES & DESIGN AND USE CURRENT LIMITATIONS 1.1. Introduction .................................................2 2.1. Introduction ...............................................56 1.1.1. Scope .........................................5 2.2. Review of CAN/CSA S6 – Canadian Highway Bridge Design Code ...................58 1.2. Wood Bridge Systems and Technology ......5 2.2.1. CAN/CSA S6 – 1.2.1. Wood Bridge Materials ...............5 Section 1 – General .................58 1.2.2. Wood Bridge Systems ...............7 2.2.2. CAN/CSA S6 – 1.2.2.1. Decks .........................................7 Section 2 – Durability ...............59 1.2.2.2. Super Structures ...................... 11 2.2.3. CAN/CSA S6 – 1.2.2.3. Sub-Structures .........................17 Section 3 – Loads ....................59 1.2.2.4. Other Systems .........................17 2.2.4. CAN/CSA S6 – Section 4 – Seismic Design .....59 1.3. Wood Bridge Design Considerations ..........17 2.2.5. CAN/CSA S6 – Section 5 – 1.3.1. Canadian Highway Bridge Methods of Analysis .................60 Design Code (CHBDC) ............18 2.2.6. CAN/CSA S6 – Section 6 – 1.3.2. MTO Ontario Provincial Foundations and Standard Specification .............18 Geotechnical Systems .............63 1.3.3. Ontario Heritage 2.2.7. CAN/CSA S6 – Section 7 – Bridge Guidelines .....................18 Buried Structures .....................63 1.3.4. Prefabrication ...........................19 2.2.8. CAN/CSA S6 – Section 8 – 1.3.5. Prestressing .............................20 Concrete Structures .................63 1.3.6. Service Life and Durability .......21 2.2.9. CAN/CSA S6 – Section 9 – Wood Structures ......................63 1.3.7. Species ....................................22 2.2.9.1 Clause 9.4 Limit States Design .64 1.3.8. International Recent Practices ..................................22 2.2.9.2. Clause 9.5 General Design ......64 1.4. Wood Bridge Protection ............................23 2.2.9.3. Clause 9.6 Flexure ...................64 1.5. Benefits of Wood Bridges..........................28 2.2.9.4. Clause 9.7 Shear .....................65 1.5.1. Cost ..........................................29 2.2.9.5. Clause 9.11 Solid wood ............65 1.5.2. Construction Cycle ...................30 2.2.9.6. Clause 9.12 Glulam timber .......66 1.5.3. Sustainability ............................30 2.2.9.7. Clause 9.15 Fastenings ............66 1.6. Wood Bridge Examples.............................33 2.2.9.8. Clause 9.17 Durability ..............67 1.6.1. Ontario Bridge Examples .........33 2.2.9.9. Clause 9.21 Nail-laminated Wood Decks .............................69 1.6.2. Other Canadian Bridge Examples ......................42 2.2.10. CAN/CSA S6 – Section 10 – Steel structures ........................70 1.6.3. American Bridge Examples .....46 2.2.11. CAN/CSA S6 – Section 11 – 1.6.4. International Bridge Joints and Bearings .................70 Examples .................................48 2.2.12. CAN/CSA S6 – Section 12 – 1.7. References ................................................52 Barriers and Highway Accessory Supports .................70 2.2.13. CAN/CSA S6 – Section 13 – Movable Bridges ......................70 Ontario Wood Bridge Reference Guide iii PART TWO – OPPORTUNITIES & PART THREE – CURRENT LIMITATIONS (cont’d) DESIGN EXAMPLES 2.2.14. CAN/CSA S6 – Section 14 – 3.2.3.3.3. Horizontal