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Design of Riprap Revetment

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Design of Riprap Revetment , 1-) r-) P .A) C? F Hydraulic Engineering Circular No. 11 U.S. Department of Transportation Federal Highway Publication Na FHWA-lP-89-016 Administration March 1989 Design of Riprap Revetment Research, Development, and-T"echnology Turner-Fairbank Highwayffesewch Center 6300 Gec rg3#own Pike McLean, V'wffiniae=-2296 WATER RESOURCES ' RESEARCH LABORATORY J OFFICIAL FILE COPY Technical Report Documentation Page 1. Report No. 2. Government Accession No. 3. Recipient's Catalog No. FHWA-IP-89-016 HEC-11 4, Title and Subtitle S. Report Dote March 1989 DESIGN OF RIPRAP REVETMENT 6. Performing Organization Code 8. Performing Organization Report No. 7, Aurhorrs) Scott A. Brown, Eric S. Clyde 9, Performing Organization Name and Address 10. Work Unit No. (TRAIS) Sutron Corporation 3D9C0033 2190 Fox Mill Road 11. Contract or Grant No. Herndon, VA 22071 DTFH61-85-C-00123 13. Type of Report and Period Covered 12. Sponsoring Agency Name and Address Office of Implementation, HRT-10 Final Report Federal Highway Administration Mar. 1986 - Sept. 1988 6200 Georgetown Pike McLean, VA 22101 14. Sponsoring Agency Code 15. Supplementary Notes Project Manager: Thomas Krylowski Technical Assistants: Philip L. Thompson, Dennis L. Richards, J. Sterling Jones 16. Abstract This revised version of Hydraulic Engineering Circular No. 11 (HEC-11), represents major revisions to the earlier (1967) edition of HEC-11. Recent research findings and revised design procedures have been incorporated. The manual has been expanded into a comprehensive design publication. The revised manual includes discussions on recognizing erosion potential, erosion mechanisms and riprap failure modes, riprap types including rock riprap, rubble riprap, gabions, preformed blocks, grouted rock, and paved linings. Design concepts included are: design discharge, flow types, channel geometry, flow resistance, extent of protection, and toe depth. Detailed design guidelines are presented for rock riprap, and design procedures are summarized in charts and examples. Design guidance is also presented for wire-enclosed rock (gabions), precast concrete blocks, and concrete paved linings. 17. Key Words 18. Distribution Statement Riprap, Revetments, Bank Protection, This document is available to the public Gabions, Grouted Riprap, Riprap Design, through the National Technical Information Pre-cast Concrete Riprap, Paved Linings. Service, Springfield, VA 22161. 19. Security Classif. (of this report) 20. Security Clossif. (of this page) 21• No. of Pages 22. Price Unclassif ied Unclassif ied 169 Form DOT F 1700.7 (8-72) Reproduction of completed page authorized METRIC (SI*) CONVERSION FACTORS APPROXIMATE CONVERSIONS TO SI UNITS APPROXIMATE CONVERSIONS TO SI UNITS Symbol When You Know Multiply By To Find Symbol Symbol When You Know Multiply By To Fk►d symbol LENGTH LENGTH . ~ n mm millimetres 0.039 Inches In In Inches 2.54 millimetres mm M metres 3.28 feet it it feet 0.3048 metres m m metres 1.09 yards yd yd yards 0.914 metres m km kilometres 0.621 miles ml mi miles 1.61 kilometres km AREA AREA N ^~ mm' millimetres squared 0.0016 square Inches in' - ~ c 10.764 square feet its In' square Inches 645.2 millimetres squared mm' m' metres squared r it, square feet 0.0929 metres squared m' km' kilometres squared 0.39 square miles mil acres ac yd' square yards 0.836 metres squared m' w he hectores (10 000 ml 2.53 mi' square miles 2.59 kilometres squared km' N• ac acres 0.395 hectares he MASS (weight) g grams 0.0353 ounces oz MASS (weight) kg kilograms 2.205 pounds lb Mg megagrams (1 000 kg) 1.103 short tons T oz ounces 28.35 grams g lb pounds 0.454 kilograms kg T VOLUME short tons (2000 lb) 0.907 megagrams Mg = w ml- millilitres 0.034 fluid ounces fi oz L litres 0.264 gallons gal VOLUME M3 metres cubed 35.315 cubic feet its m' metres cubed 1.308 cubic yards yd' fl oz fluid ounces 29.57 millilitres mL gat gallons 3.785 litres L it, cubic feet 0.0328 metres cubed m' TEMPERATURE (exact) yd' cubic yards 0.0765 metres cubed m' °C Celsius 9/5 (then Fahrenheit OF NOTE: Volumes greater than 1000 L shall be shown In m'. temperature add 32) temperature OF OF 32 96.6 212 -40 40 2001 80 1120. 160 TEMPERATURE (exact) 0 — ji-—r --` sl - 20 0 i '. W ' 8080 100 37 OF Fahrenheit 519 (after Celsius °C temperature subtracting 32) temperature These factors conform to the requirement of FHWA Order 5190.11A. SI is the symbol for the International System of Measurements 4 TABLE OF CONTENTS Section Paae - 1. INTRODUCTION ........................................................................................................................ 1 1.1. SCOPE ............................................................................................................................................ 1 1.2. RECOGNITION OF EROSION POTENTIAL ........................................................... 2 1.3. EROSION MECHANISMS AND RIPRAP FAILURE MODES ........................ 3 2. REVETMENT TYPES ...................................................».......................................................... 7 2.1. RIPRAP ....................................................................................................................................... 7 2.2. WIRE-ENCLOSED ROCK .............................................................................................. 11 2.3. PRE-CAST CONCRETE BLOCK ................................................................................... 14 2.4. GROUTED ROCK ................................................................................................................. 15 2.5. PAVED LINING ..................................................................................................................... 16 3. DESIGN CONCEPTS ................................................................................................................. 19 3.1. DESIGN DISCHARGE ......................................................................................................... 19 3.2. FLOW TYPES .......................................................................................................................... 19 3.3. SECTION GEOMETRY ....................................................................................................... 20 3.4. FLOW IN CHANNEL BENDS ............................................»........................................... 21 3.5. FLOW RESISTANCE ..................................................»..».........»......................................... 23 ; 3.6. EXTENT OF PROTECTION ..................... .. ....... ..... ...... .» .... ....»..... ............. _.................. 24 4. DESIGN GUIDELINES FOR ROCK RIPRAP ............................................................. 29 4.1. ROCK SIZE ............................................................................................................................... 29 4.2. ROCK GRADATION ........................................................................................................... 36 4.3. LAYER THICKNESS ........................................................................................................... 37 4.4. FILTER DESIGN .................................................................................................................... 38 4.5. MATERIAL QUALITY ....................................................................................................... 41 4.6. EDGE TREATMENT ........................................................................................................... 42 4.7. CONSTRUCTION .................................................................................................................. 42 5. ROCK RIPRAP DESIGN PROCEDURE ......................................................................... 47 5.1. PRELIMINARY DATA ANALYSIS ................................................................ ............. 47 5.2. ROCK SIZING (form 1) ....................................................................................................... 47 5.3. REVETMENT DETAILS .................................................................................................... 50 5.4. DESIGN EXAMPLES ................................ 6. GUIDELINES FOR OTHER REVETMENTS ................................................................ 79 6.1. WIRE-ENCLOSED ROCK .................................................................................................. 79 6.2. PRE-CAST CONCRETE BLOCKS ................................................................................. 94 6.3. GROUTED ROCK ................................................................................................................. 99 6.4. CONCRETE PAVEMENT .................................................................................................. 103 iii TABLE OF CONTENTS (continued) Section Paae 7. APPENDIX A: Suggested Specifications ......................................................................... 109 7.1. RIPRAP ....................................................................................................................................... 109 7.2. WIRE-ENCLOSED ROCK .................................................................................................. 114 7.3. GROUTED ROCK RIPRAP ............................................................................................. 115 7.4. PRE-CAST CONCRETE BLOCKS ................................................................................. 116 7.5. PAVED LINING ....................................................................................................................
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