COPY NO. # Guidelines for Certification and Management of Rockfall Fence Systems Final Report Prepared for National Cooperative Highway Research Program, Project 24‐35 Transportation Research Board of The National Academies of Sciences, Engineering and Medicine Ben Arndt, P.E., P.G. Brett Arpin, P.E. Yeh and Associates, Inc. Denver, CO Jerry D. Higgins, Ph.D., P.G. Consulting Engineering Geologist Golden, CO Paul Thompson Consultant Bellevue, WA December 2015 ACKNOWLEDGEMENT OF SPONSORSHIP This work was sponsored by the American Association of State Highway and Transportation Officials, in cooperation with the Federal Highway Administration, and was conducted in the National Cooperative Highway Research Program, which is administered by the Transportation Research Board of the National Academies Sciences, Engineering, and Medicine. DISCLAIMER This is an uncorrected draft as submitted by the contractor. The opinions and conclusions expressed or implied herein are those of the contractor. They are not necessarily those of the Transportation Research Board, the National Academies, or the program sponsors. ii Guidelines for Certification and Management of Rockfall Fence Systems Final Report Prepared for National Cooperative Highway Research Program, Project 24‐35 Transportation Research Board of The National Academies of Sciences, Engineering and Medicine Ben Arndt, P.E., P.G. Brett Arpin, P.E. Yeh and Associates, Inc. Denver, CO Jerry D. Higgins, Ph.D., P.G. Consulting Engineering Geologist Golden, CO Paul Thompson Consultant Bellevue, WA December 2015 iii CONTENTS LIST OF FIGURES .................................................................................................................... VII LIST OF TABLES ..................................................................................................................... VIII LIST OF APPENDICES ............................................................................................................... IX AUTHOR ACKNOWLEDGEMENTS ............................................................................................. X ABSTRACT ............................................................................................................................... XI SUMMARY ............................................................................................................................... 1 CHAPTER 1 ............................................................................................................................... 2 Background ......................................................................................................................... 2 1.1 Problem Statement .................................................................................................................................... 2 1.1.1 Certification of Rockfall Fence Systems in the United States ........................................................ 2 1.1.2 Asset Management of Flexible Rockfall Fence Systems ................................................................ 2 1.2 Research Objectives ................................................................................................................................... 3 CHAPTER 2 ............................................................................................................................... 4 Research Approach ............................................................................................................. 4 2.1 Project Overview ........................................................................................................................................ 4 2.2 Review Previous Rockfall Fence Testing Standards .................................................................................... 4 2.3 Review of Previous Geotechnical Asset Inventory and Assessment Systems ............................................ 4 2.4 Review of Transportation and Geotechnical Asset Management .............................................................. 5 2.5 Survey Input from Transportation Agencies, Designers, and Manufacturers Regarding Rockfall Fence Systems ............................................................................................................................................ 5 CHAPTER 3 ............................................................................................................................... 7 Review of Flexible Rockfall Fence Testing Definitions, Standards, and Guidelines ............... 7 3.1 Rockfall Protection System Definitions ...................................................................................................... 7 3.2 Discussion on Rockfall Fence Testing Delivery Methods ............................................................................ 9 3.2.1 Rock Rolling Tests .......................................................................................................................... 9 3.2.2 Inclined Cable Type Tests ............................................................................................................ 10 3.2.3 Vertical Drop Tests ...................................................................................................................... 11 3.2.4 Pendulum Type Tests .................................................................................................................. 12 3.2.5 Comparison of Rockfall Fence Testing Delivery Methods ........................................................... 12 3.3 Overview of Rockfall Fence Testing Programs, Standards, and Guidelines .............................................. 13 3.3.1 Rockfall Fence Testing In 1980s ................................................................................................... 13 3.3.2 Rockfall Fence Testing In 1990s ................................................................................................... 15 iv 3.3.3 Rockfall Fence Testing In 2000 to Present ................................................................................... 19 3.3.3.1 Swiss Testing ................................................................................................................. 19 3.3.3.2 Geobrugg North America Testing .................................................................................. 20 3.3.3.3 Italian Testing ................................................................................................................ 20 3.3.3.4 Colorado Attenuator Testing ......................................................................................... 21 3.3.3.5 Austrian Testing ............................................................................................................ 22 3.3.3.6 Colorado Rockfall Fence and Post Foundation Systems Testing ................................... 22 3.3.4 Early United States Rockfall Fence Performance Standards and Guidelines ............................... 24 3.3.5 Early Italian Rockfall Fence Testing Standards ............................................................................ 26 3.3.6 Swiss Rockfall Fence Performance Standards and Guidelines .................................................... 26 3.3.7 United States NCHRP 20‐07 Testing Guidelines .......................................................................... 30 3.3.8 European ETAG 27 Testing Standards ......................................................................................... 31 3.4 Comparison of SAEFL, NCHRP 20‐07, and ETAG 27 .................................................................................. 35 CHAPTER 4 ............................................................................................................................. 39 Review of Flexible Rockfall Fence Inventory, Assessment and Management Systems ....... 39 4.1 Overview Asset Management .................................................................................................................. 39 4.2 Austrian Rockfall System Inspection and Maintenance Guidelines ......................................................... 40 4.3 Canadian Rockfall Site and System Inspection and Maintenance Practices ............................................. 41 4.4 Comparison with Retaining Wall Inventory and Condition Assessment Methods ................................... 42 4.4.1 Examples of WIP Field Forms for Wall Systems........................................................................... 42 4.4.2 Example of Definitions, Conditions and Performance Ratings for Wall Systems ........................ 45 CHAPTER 5 ............................................................................................................................. 47 Research Results ............................................................................................................... 47 5.1 Overview ................................................................................................................................................... 47 5.2 Survey Results ........................................................................................................................................... 47 5.2.1 Background Section Results ........................................................................................................ 47 5.2.2 Standards and Certifications Section Results .............................................................................. 48 5.2.3 Design and Construction Section Results ...................................................................................