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Design Considerations for Embankment Protection During Road June 2017 Overtopping Events 6

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Design Considerations for Embankment Protection During Road June 2017 Overtopping Events 6 ĞƐŝŐŶŽŶƐŝĚĞƌĂƚŝŽŶƐ ĨŽƌŵďĂŶŬŵĞŶƚ WƌŽƚĞĐƚŝŽŶƵƌŝŶŐZŽĂĚ KǀĞƌƚŽƉƉŝŶŐǀĞŶƚƐ :ĞĨĨƌĞLJ͘'͘DĂƌƌ͕WƌŝŶĐŝƉĂů/ŶǀĞƐƚŝŐĂƚŽƌ ^ƚ͘ŶƚŚŽŶLJ&ĂůůƐ>ĂďŽƌĂƚŽƌLJ ĞƉĂƌƚŵĞŶƚŽĨŝǀŝů͕ŶǀŝƌŽŶŵĞŶƚĂů͕ĂŶĚ'ĞŽͲŶŐŝŶĞĞƌŝŶŐ University of Minnesota :ƵŶĞϮϬϭϳ Research Project Final Report 2017-Ϯϭ • ŵŶĚŽƚ͘ŐŽǀͬƌĞƐĞĂƌĐŚ To request this document in an alternative format, such as braille or large print, call 651-366-4718 or 1- 800-657-3774 (Greater Minnesota) or email your request to [email protected]. Please request at least one week in advance. Technical Report Documentation Page 1. Report No. 2. 3. Recipients Accession No. MN/RC 2017-21 4. Title and Subtitle 5. Report Date Design Considerations for Embankment Protection During Road June 2017 Overtopping Events 6. 7. Author(s) 8. Performing Organization Report No. Jeffrey D. G. Marr, Matthew Hernick, Robert Gabrielson, Sara Mielke 9. Performing Organization Name and Address 10. Project/Task/Work Unit No. St. Anthony Falls Laboratory CTS# 2013034 University of Minnesota 11. Contract (C) or Grant (G) No. 2 SE 3rd Ave (C) 99008 (wo) 50 Minneapolis, MN 55414 12. Sponsoring Organization Name and Address 13. Type of Report and Period Covered Minnesota Local Road Research Board Final Report Minnesota Department of Transportation 14. Sponsoring Agency Code Research Services & Library 395 John Ireland Boulevard, MS 330 St. Paul, Minnesota 55155-1899 15. Supplementary Notes http:// mndot.gov/research/reports/2017/201721.pdf 16. Abstract (Limit: 250 words) This report describes the research conducted by the University of Minnesota and project partners on roadway embankment overtopping by flood water. Roadway overtopping is a major safety concern for Minnesota transportation managers because of the potential for rapid soil erosion and mass wasting resulting in partial or complete failure of the roadway embankment. This multi-year research study focused on various aspects of the roadway embankment overtopping. A robust literature survey was performed to identify research, reports and other published knowledge that would inform the project. A field- based research campaign was developed with the goal of collecting data on the hydraulics associated with full-scale overtopping events. Finally, a series of laboratory experiments were conducted at the St. Anthony Falls Laboratory, University of Minnesota to study the hydraulic and erosional processes associated with embankment overtopping and in particular study of three slope protection techniques under overtopping flow. The largest component of the research project was the laboratory hydraulic testing, which focused on bare soil (base case) and three slope protection technologies. A full- scale laboratory facility was constructed to carry out the testing. Three erosion protection techniques were examined including 1) armored sod, 2) turf reinforcement mat, and 3) flexible concrete geogrid mat. Overtopping depths of up to 1-ft were used to determine the failure point of the protection technique and soil on both the 4h:1V and 6V:1H slopes. The full project report details the testing of each protection technique as well as observations and findings made during the testing. 17. Document Analysis/Descriptors 18. Availability Statement overtopping, embankments, laboratory tests, hydraulics, No restrictions. Document available from: erosion National Technical Information Services, Alexandria, Virginia 22312 19. Security Class (this report) 20. Security Class (this page) 21. No. of Pages 22. Price Unclassified Unclassified 216 Design Considerations for Embankment Protection During Road Overtopping Events FINAL REPORT Prepared by: Jeffrey D. G. Marr Matthew Hernick Robert Gabrielson Sara Mielke St. Anthony Falls Laboratory Department of Civil, Environmental, and Geo- Engineering University of Minnesota June 2017 Published by: Minnesota Department of Transportation Research Services & Library 395 John Ireland Boulevard, MS 330 St. Paul, Minnesota 55155-1899 This report represents the results of research conducted by the authors and does not necessarily represent the views or policies of the Minnesota Department of Transportation or the University of Minnesota. This report does not contain a standard or specified technique. The authors, the Minnesota Department of Transportation, and the University of Minnesota do not endorse products or manufacturers. Trade or manufacturers’ names appear herein solely because they are considered essential to this report because they are considered essential to this report. ACKNOWLEDGMENTS The authors would like to thank the members of the Technical Advisory Panel (TAP) for their support and valuable input. TAP members included J.T. Anderson (Technical Liaison), Alan Rindels (Administrative Liaison), Daniel Sullivan (Administrative Liaison), Mitch Bartelt (Administrative Liaison), Lori Belz, Graig Gilbertson, Andrea Hendrickson, and Dwayne Stenlund. Several members of the technical staff at St. Anthony Falls Laboratory (SAFL) contributed along the course of the project, including the author of the MATLAB code, Chris Milliren. Craig Taylor served as the initial Principal Investigator. Several persons and organizations generously donated materials and/or installation expertise, including Matt Motz and Sean Stallo of Motz Enterprises, manufacturers of Flexamat®, Greg Halvorsen of Brock White Construction Materials, Michael T. Ramy, Jr. of Ramy Turf Products, and Nick Kentros of Tri-State Bobcat, Inc. Special thanks to Luke Riveness, undergraduate student engineering from Bethel University, for his commitment to the laboratory work over the summer of 2015. TABLE OF CONTENTS CHAPTER 1: Introduction ....................................................................................................................1 1.1 Roadway Overtopping ........................................................................................................................ 1 1.2 Project Objective ................................................................................................................................ 2 1.3 Scope of Present Research ................................................................................................................. 5 1.4 Project Team ....................................................................................................................................... 5 CHAPTER 2: Previous Studies and Relevant Literature .........................................................................6 2.1 Roadway Overtopping ........................................................................................................................ 6 2.1.1 Discharge Characteristics of an Embankment-Shaped Weir ....................................................... 6 2.1.2 Federal Highway Administration FHWA – RD-86-126 ................................................................. 6 2.1.3 Federal Highway Administration FHWA-RD-88-181 ................................................................... 7 2.1.4 Hydraulic Stability of Conlock and Conlock II Concrete Block Revetment System during Overtopping Flow (St. Anthony Falls Laboratory, University of Minnesota, Project Report No. 369) 8 2.1.5 Hydraulic Stability of Channel LockTM Concrete Block Revetment System during Overtopping Flow (St. Anthony Falls Laboratory, University of Minnesota, Project Report No. 396) ..................... 9 2.1.6 Hydraulic Stability of Hand Placed Positive Interlocking Concrete Block Revetment System during Overtopping Flow (St. Anthony Falls Laboratory, University of Minnesota, Project Report No. 428) ...................................................................................................................................................... 9 2.1.7 Protecting Road Embankments from Overtopping Flow ............................................................ 9 2.2 Additional References......................................................................................................................... 9 2.2.1 Stability of riprap and discharge characteristics, overflow embankments, Arkansas River, Arkansas: Hydraulic model investigation ........................................................................................... 10 2.2.2 Riprap Design for Overtopping Flow ......................................................................................... 10 2.2.3 Physical Modeling of Overtopping Erosion and Breach Formation of Cohesive Embankments ............................................................................................................................................................ 10 2.2.4 Hydraulics of Embankment Weirs ............................................................................................. 10 2.2.5 Embankment overtopping protection systems ......................................................................... 11 2.2.6 A Study of Embankment Performance during Overtopping ..................................................... 11 2.2.7 Stabilization of Angular-Shaped Riprap under Overtopping Flows ........................................... 11 2.2.8 Evaluation of Overtopping Riprap Design Relationships........................................................... 11 2.2.9 Enhanced Stone Sizing for Overtopping Flow ........................................................................... 12 CHAPTER 3: Laboratory Test Methods .............................................................................................. 13 3.1 Experimental Setup .........................................................................................................................
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