National Academies Press: OpenBook

Effects of Debris on Bridge Pier Scour (2010)

Chapter:Front Matter

Page i
Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2010. Effects of Debris on Bridge Pier Scour. Washington, DC: The National Academies Press. doi: 10.17226/22955.
×
PageR1
Page ii
Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2010. Effects of Debris on Bridge Pier Scour. Washington, DC: The National Academies Press. doi: 10.17226/22955.
×
PageR2
Page iii
Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2010. Effects of Debris on Bridge Pier Scour. Washington, DC: The National Academies Press. doi: 10.17226/22955.
×
PageR3
Page iv
Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2010. Effects of Debris on Bridge Pier Scour. Washington, DC: The National Academies Press. doi: 10.17226/22955.
×
PageR4
Page v
Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2010. Effects of Debris on Bridge Pier Scour. Washington, DC: The National Academies Press. doi: 10.17226/22955.
×
PageR5
Page vi
Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2010. Effects of Debris on Bridge Pier Scour. Washington, DC: The National Academies Press. doi: 10.17226/22955.
×
PageR6
Page vii
Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2010. Effects of Debris on Bridge Pier Scour. Washington, DC: The National Academies Press. doi: 10.17226/22955.
×
PageR7
Page viii
Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2010. Effects of Debris on Bridge Pier Scour. Washington, DC: The National Academies Press. doi: 10.17226/22955.
×
PageR8

Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

TRANSPORTAT ION RESEARCH BOARD WASHINGTON, D.C. 2010 www.TRB.org N A T I O N A L C O O P E R A T I V E H I G H W A Y R E S E A R C H P R O G R A M NCHRP REPORT 653 Subscriber Categories Bridges and Other Structures • Geotechnology • Hydraulics and Hydrology Effects of Debris on Bridge Pier Scour P. F. Lagasse P. E. Clopper L. W. Zevenbergen W. J. Spitz L. G. Girard AYRES ASSOCIATES, INC. Fort Collins, CO Research sponsored by the American Association of State Highway and Transportation Officials in cooperation with the Federal Highway Administration

NATIONAL COOPERATIVE HIGHWAY RESEARCH PROGRAM Systematic, well-designed research provides the most effective approach to the solution of many problems facing highway administrators and engineers. Often, highway problems are of local interest and can best be studied by highway departments individually or in cooperation with their state universities and others. However, the accelerating growth of highway transportation develops increasingly complex problems of wide interest to highway authorities. These problems are best studied through a coordinated program of cooperative research. In recognition of these needs, the highway administrators of the American Association of State Highway and Transportation Officials initiated in 1962 an objective national highway research program employing modern scientific techniques. This program is supported on a continuing basis by funds from participating member states of the Association and it receives the full cooperation and support of the Federal Highway Administration, United States Department of Transportation. The Transportation Research Board of the National Academies was requested by the Association to administer the research program because of the Board’s recognized objectivity and understanding of modern research practices. The Board is uniquely suited for this purpose as it maintains an extensive committee structure from which authorities on any highway transportation subject may be drawn; it possesses avenues of communications and cooperation with federal, state and local governmental agencies, universities, and industry; its relationship to the National Research Council is an insurance of objectivity; it maintains a full-time research correlation staff of specialists in highway transportation matters to bring the findings of research directly to those who are in a position to use them. The program is developed on the basis of research needs identified by chief administrators of the highway and transportation departments and by committees of AASHTO. Each year, specific areas of research needs to be included in the program are proposed to the National Research Council and the Board by the American Association of State Highway and Transportation Officials. Research projects to fulfill these needs are defined by the Board, and qualified research agencies are selected from those that have submitted proposals. Administration and surveillance of research contracts are the responsibilities of the National Research Council and the Transportation Research Board. The needs for highway research are many, and the National Cooperative Highway Research Program can make significant contributions to the solution of highway transportation problems of mutual concern to many responsible groups. The program, however, is intended to complement rather than to substitute for or duplicate other highway research programs. Published reports of the NATIONAL COOPERATIVE HIGHWAY RESEARCH PROGRAM are available from: Transportation Research Board Business Office 500 Fifth Street, NW Washington, DC 20001 and can be ordered through the Internet at: http://www.national-academies.org/trb/bookstore Printed in the United States of America NCHRP REPORT 653 Project 24-26 ISSN 0077-5614 ISBN 978-0-309-11834-7 Library of Congress Control Number 2010926176 © 2010 National Academy of Sciences. All rights reserved. COPYRIGHT INFORMATION Authors herein are responsible for the authenticity of their materials and for obtaining written permissions from publishers or persons who own the copyright to any previously published or copyrighted material used herein. Cooperative Research Programs (CRP) grants permission to reproduce material in this publication for classroom and not-for-profit purposes. Permission is given with the understanding that none of the material will be used to imply TRB, AASHTO, FAA, FHWA, FMCSA, FTA, or Transit Development Corporation endorsement of a particular product, method, or practice. It is expected that those reproducing the material in this document for educational and not-for-profit uses will give appropriate acknowledgment of the source of any reprinted or reproduced material. For other uses of the material, request permission from CRP. NOTICE The project that is the subject of this report was a part of the National Cooperative Highway Research Program, conducted by the Transportation Research Board with the approval of the Governing Board of the National Research Council. The members of the technical panel selected to monitor this project and to review this report were chosen for their special competencies and with regard for appropriate balance. The report was reviewed by the technical panel and accepted for publication according to procedures established and overseen by the Transportation Research Board and approved by the Governing Board of the National Research Council. The opinions and conclusions expressed or implied in this report are those of the researchers who performed the research and are not necessarily those of the Transportation Research Board, the National Research Council, or the program sponsors. The Transportation Research Board of the National Academies, the National Research Council, and the sponsors of the National Cooperative Highway Research Program do not endorse products or manufacturers. Trade or manufacturers’ names appear herein solely because they are considered essential to the object of the report.

CRP STAFF FOR NCHRP REPORT 653 Christopher W. Jenks, Director, Cooperative Research Programs Crawford F. Jencks, Deputy Director, Cooperative Research Programs David A. Reynaud, Senior Program Officer Megan A. Chamberlain, Senior Program Assistant Eileen P. Delaney, Director of Publications Natalie Barnes, Editor NCHRP PROJECT 24-26 PANEL Field of Soils and Geology—Area of Mechanics and Foundations William Oliva, Wisconsin DOT, Madison, WI (Chair) Brian L. Beucler, Federal Highway Administration, Sterling, VA Merril E. Dougherty, Indiana DOT, Indianapolis, IN Robert Ettema, University of Wyoming, Laramie, WY Kevin Scott Flora, California DOT, Sacramento, CA James Lane, New Jersey DOT, Trenton, NJ Jon K. Zirkle, Tennessee DOT, Nashville, TN David D. Zwernemann, Texas DOT, Austin, TX Kornel Kerenyi, FHWA Liaison Frank N. Lisle, TRB Liaison C O O P E R A T I V E R E S E A R C H P R O G R A M S

This report provides guidelines for practitioners to estimate the quantity of accumulated, flow event debris, based on the density and type of woody vegetation and river bank condi- tion upstream and analytical procedures to quantify the effects of resulting debris-induced scour on bridge piers. The report should be of interest to bridge engineers, maintenance personnel and operations staff at state and local agencies. As every organization that designs, operates, and maintains bridges is well aware, bridge scour is a problem that can have catastrophic effects. It is well known, since the 1980 col- lapse of a part of the Perkins Road Bridge over Nonconnah Creek in Memphis, Tennessee, that the accumulation of floating debris in the form of tree trunks and limbs during flood events plays a critical role in the occurrence of scour at bridge piers. In the investigation that followed the Perkins Road collapse, engineers found that a 20% blockage between piers would alter flow conditions and undermine the 12 ft of embedment on the piles support- ing the pier that failed. The best information to provide to these bridge owners, to help them cut this problem down to manageable size, is improved prediction techniques to foresee the development and shape of debris accumulation and the resulting extent of scour at the bridge piers. This research performed by Ayres Associates Inc. under NCHRP Project 24- 26, “Effects of Debris on Bridge Pier Scour,” provides methods to create these prediction techniques. The research methods employed during the course of this study include a literature review, a survey of bridge owners to determine current practices, and creation of a photo- graphic archive to help predict the size and shape of accumulated debris. Results of a flume study are provided to establish relationships between the size and shape of accumulated debris and the resulting pier scour. These methods are all illustrated by example problem solutions and case studies to facilitate understanding. In addition to this published report, the debris photographic archive, the survey questionnaire and list of respondents, and the report on the field pilot study are available on the TRB website (www.trb.org) as NCHRP Web-Only Document 148 (search for “NCHRP Web-Only Document 148”). F O R E W O R D By David A. Reynaud Staff Officer Transportation Research Board

AUTHOR ACKNOWLEDGMENTS This work was sponsored by the American Association of State Highway and Transportation Officials (AASHTO), in cooperation with the Federal Highway Administration (FHWA), and was conducted through the National Cooperative Highway Research Program (NCHRP), which is administered by the Transportation Research Board (TRB) of the National Academies. The research reported herein was performed under NCHRP Project 24-26 by Ayres Associates Inc., Fort Collins, Colorado. Dr. P.F. Lagasse, Senior Vice President, served as Principal Investigator and Mr. P.E. Clopper, Senior Water Resources Engineer, served as Co-Principal Investigator. They were assisted by Dr. L.W. Zevenbergen, Manager River Engineering; Mr. W. J. Spitz, Senior Geomorphologist; and Ms. L.G. Girard, Hydraulic Engineer. Mr. G.R. Price of ETI Instrument Systems, Fort Collins, Colorado, provided support for adapting the instrumentation for the articulated arm to measure the geometry of debris clusters and accompanied the research team on the field pilot study in Kansas. A special acknowledgment is due Mr. Bradford Rognlie, Bridge Squad Leader, Kansas Department of Transportation (DOT), for his enthusiastic response to the survey, his invaluable support for the field pilot study of debris-prone bridges in Kansas, and his interest throughout the project. The core of the photographic archive in Appendix A, which provided a cost- effective substitute for extensive field work, was provided by Mr. Mike Collier, Debris Free, Inc., Ojai, Cal- ifornia, from a collection of photographs he assembled during site visits around the United States. The research team would also like to thank the 88 respondents to the survey, which included 30 state DOTs and Puerto Rico. Your interest underscores the pervasive nature of the debris problem at bridges. Hope- fully the results of this research will justify the time you invested in your responses. We must also recog- nize the pioneering work by Mr. Tim Diehl of the United States Geological Survey and Dr. Bruce Melville and Mr. D.M.S. Dongol of the University of Auckland, New Zealand, that provided the foundation for the advances made in this study. All laboratory testing was performed at the Colorado State University Engineering Research Center Hydraulics Laboratory under the direction of Dr. Chris Thornton and Mr. Michael Robison. The assis- tance of Mr. Sean Kimbrel, graduate student; Mr. Matt Stockton, lab technician; and Mr. Mick Ursic, undergraduate student is also acknowledged. The participation, advice, and support of NCHRP Project 24-26 panel members throughout this project are gratefully acknowledged.

C O N T E N T S 1 Summary 4 Chapter 1 Introduction and Research Approach 4 1.1 Scope and Research Objectives 4 1.1.1 Background 4 1.1.2 Objectives 5 1.2 Research Approach 5 1.2.1 Overview 6 1.2.2 Research Plan Modifications 6 1.3 Research Tasks 6 1.3.1 Phase 1 Tasks 7 1.3.2 Phase 2 Tasks 8 1.4 Research Results 8 1.5 Documentation Organization 9 Chapter 2 Findings 9 2.1 Review of Current Practice 9 2.1.1 Introduction 10 2.1.2 Debris Source Loading, Distribution, and Recruitment 11 2.1.3 Debris Transport 15 2.1.4 Debris Deposition, Accumulation, and Storage 17 2.1.5 Debris Accumulation at Bridge Piers 19 2.1.6 Modeling Debris-Induced Hydrodynamic Forces and Scour 21 2.1.7 Managing Debris Accumulations at Bridges 24 2.2 Debris Photographic Archive 24 2.3 Regional Analysis of Debris 34 2.4 Survey and Site Reconnaissance 34 2.4.1 Survey 35 2.4.2 Analysis of Survey Responses 39 2.5 Site Reconnaissance 39 2.5.1 Equipment and Preparation 39 2.5.2 Field Pilot Study 39 2.5.3 Field Pilot Study Results 40 2.5.4 Recommendations 41 Chapter 3 Guidelines, Testing, Appraisal, and Results 41 3.1 Introduction 41 3.2 Guidelines for Assessing Debris Production, Transport Delivery, and Accumulation Potential 42 3.2.1 Phase 1: Evaluate Potential for Debris Production and Delivery 48 3.2.2 Phase 2: Estimate Potential for Debris Accumulation on Individual Bridge Elements 50 3.2.3 Phase 3: Determine the Overall Debris Accumulation Potential for the Bridge

52 3.3 Application of the Guidelines: South Platte River Case Study 52 3.3.1 Field Reconnaissance 53 3.3.2 Development of the Case Study 53 3.4 Development of Debris Characteristics for Laboratory Testing 53 3.4.1 Debris Accumulation Characteristics 58 3.4.2 Laboratory Testing of Debris 60 3.5 Laboratory Testing Program 60 3.5.1 Testing Facilities and Protocols 70 3.5.2 Debris Cluster Test Materials 72 3.5.3 Baseline Tests 76 3.5.4 Tests with Debris 79 3.6 Appraisal of Testing Results 79 3.6.1 Baseline (No-Debris) Tests 85 3.6.2 Tests with Debris 90 3.7 Scour Prediction at Bridge Piers with Debris Loading 90 3.7.1 Introduction 92 3.7.2 Equivalent Pier Width 94 3.7.3 Recommended Design Equation 94 3.7.4 Effect of Debris Roughness and Porosity 94 3.7.5 Effect of Debris Location in the Water Column 96 3.7.6 Lateral Extent of Scour at Piers with Debris 97 3.8 Incorporating Debris in Hydraulic Models 97 3.8.1 HEC-RAS 98 3.8.2 Two-Dimensional Models 99 3.9 Application Methodology and Examples 99 3.9.1 Methodology 100 3.9.2 Example Debris Scour Calculations 102 3.10 Guidelines for Inspection, Monitoring, and Maintenance 102 3.10.1 Inspection 103 3.10.2 Monitoring 104 3.10.3 Maintenance 105 3.11 Implementation Plan 105 3.11.1 The Product 105 3.11.2 The Market 105 3.11.3 Impediments to Implementation 105 3.11.4 Leadership in Action 106 3.11.5 Activities for Implementation 106 3.11.6 Criteria for Success 107 Chapter 4 Conclusions and Suggested Research 107 4.1 Applicability of Results to Highway Practice 107 4.2 Conclusions and Recommendations 107 4.2.1 Overview 108 4.2.2 Advances in the State of Practice 110 4.2.3 Deliverables 111 4.3 Suggested Research 112 References A-1 APPENDIX A Debris Photographic Archive B-1 APPENDIX B Survey of Practitioners C-1 APPENDIX C Field Pilot Study Report D-1 APPENDIX D Field Data Sheets and Case Study

Next: Summary »
Effects of Debris on Bridge Pier Scour Get This Book
×
MyNAP members save 10% online.
Login or Register to save!
Download Free PDF

TRB’s National Cooperative Highway Research Program (NCHRP) Report 653: Effects of Debris on Bridge Pier Scour explores guidelines to help estimate the quantity of accumulated, flow event debris, based on the density and type of woody vegetation and river bank condition upstream and analytical procedures to quantify the effects of resulting debris-induced scour on bridge piers.

The debris photographic archive, the survey questionnaire and list of respondents, and the report on the field pilot study related to development of NCHRP 653 was published as NCHRP Web-Only Document 148: Debris Photographic Archive and Supplemental Materials for NCHRP Report 653.

  1. ×

    Welcome to OpenBook!

    You're looking at OpenBook, NAP.edu's online reading room since 1999. Based on feedback from you, our users, we've made some improvements that make it easier than ever to read thousands of publications on our website.

    Do you want to take a quick tour of the OpenBook's features?

    No Thanks Take a Tour »
  2. ×

    Show this book's table of contents, where you can jump to any chapter by name.

    « Back Next »
  3. ×

    ...or use these buttons to go back to the previous chapter or skip to the next one.

    « Back Next »
  4. ×

    Jump up to the previous page or down to the next one. Also, you can type in a page number and press Enter to go directly to that page in the book.

    « Back Next »
  5. ×

    To search the entire text of this book, type in your search term here and press Enter.

    « Back Next »
  6. ×

    Share a link to this book page on your preferred social network or via email.

    « Back Next »
  7. ×

    View our suggested citation for this chapter.

    « Back Next »
  8. ×

    Ready to take your reading offline? Click here to buy this book in print or download it as a free PDF, if available.

    « Back Next »
Stay Connected!