Crashworthy Work-Zone Traffic Control Devices (2006)

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T R A N S P O R T A T I O N R E S E A R C H B O A R D WASHINGTON, D.C. 2006 www.TRB.org NATIONAL COOPERATIVE HIGHWAY RESEARCH PROGRAM NCHRP REPORT 553 Research Sponsored by the American Association of State Highway and Transportation Officials in Cooperation with the Federal Highway Administration SUBJECT AREAS Highway Operations, Capacity, and Traffic Control Crashworthy Work-Zone Traffic Control Devices ROGER P. BLIGH WANDA L. MENGES REBECCA R. HAUG Texas Transportation Institute College Station, TX

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. Note: The Transportation Research Board of the National Academies, the National Research Council, the Federal Highway Administration, the American Association of State Highway and Transportation Officials, and the individual states participating in 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 this report. 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 553 Project 22-18 ISSN 0077-5614 ISBN 0-309-09742-8 Library of Congress Control Number 2005938959 © 2006 Transportation Research Board Price $36.00 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. Such approval reflects the Governing Board’s judgment that the program concerned is of national importance and appropriate with respect to both the purposes and resources of the National Research Council. The members of the technical committee selected to monitor this project and to review this report were chosen for recognized scholarly competence and with due consideration for the balance of disciplines appropriate to the project. The opinions and conclusions expressed or implied are those of the research agency that performed the research, and, while they have been accepted as appropriate by the technical committee, they are not necessarily those of the Transportation Research Board, the National Research Council, the American Association of State Highway and Transportation Officials, or the Federal Highway Administration, U.S. Department of Transportation. Each report is reviewed and accepted for publication by the technical committee according to procedures established and monitored by the Transportation Research Board Executive Committee and the Governing Board of the National Research Council.

The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished schol- ars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. On the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and techni- cal matters. Dr. Ralph J. Cicerone is president of the National Academy of Sciences. The National Academy of Engineering was established in 1964, under the charter of the National Acad- emy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achieve- ments of engineers. Dr. William A. Wulf is president of the National Academy of Engineering. The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, on its own initiative, to identify issues of medical care, research, and education. Dr. Harvey V. Fineberg is president of the Institute of Medicine. The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy’s purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Acad- emy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both the Academies and the Institute of Medicine. Dr. Ralph J. Cicerone and Dr. William A. Wulf are chair and vice chair, respectively, of the National Research Council. The Transportation Research Board is a division of the National Research Council, which serves the National Academy of Sciences and the National Academy of Engineering. The Board’s mission is to promote innovation and progress in transportation through research. In an objective and interdisciplinary setting, the Board facilitates the sharing of information on transportation practice and policy by researchers and practitioners; stimulates research and offers research management services that promote technical excellence; provides expert advice on transportation policy and programs; and disseminates research results broadly and encourages their implementation. The Board’s varied activities annually engage more than 5,000 engineers, scientists, and other transportation researchers and practitioners from the public and private sectors and academia, all of whom contribute their expertise in the public interest. The program is supported by state transportation departments, federal agencies including the component administrations of the U.S. Department of Transportation, and other organizations and individuals interested in the development of transportation. www.TRB.org www.national-academies.org

COOPERATIVE RESEARCH PROGRAMS STAFF FOR NCHRP REPORT 553 ROBERT J. REILLY, Director, Cooperative Research Programs CRAWFORD F. JENCKS, Manager, NCHRP CHARLES W. NIESSNER, Senior Program Officer EILEEN P. DELANEY, Director of Publications NATALIE BARNES, Editor NCHRP PROJECT 22-18 PANEL Field of Design—Area of Vehicle Barrier Systems LAUREL BRYDEN, New York State DOT (Chair) NICHOLAS A. ARTIMOVICH, FHWA, Washington, DC MARK R. BORTLE, Iowa DOT MCCARTHY K. BRAXTON, Ohio DOT DON J. GRIPNE, Trinity Industries, Inc., Olympia, WA JOSEPH DANIEL MAUPIN, College Station, TX RICHARD R. PETER, Elk Grove, CA LEE J. ROADIFER, Wyoming DOT HARRY W. TAYLOR, JR., FHWA, Washington, DC JERRY W. WEKEZER, Florida State University MORT OSKARD, FHWA Liaison STEPHEN F. MAHER, TRB Liaison

This report presents the findings of a research project to develop nonproprietary, crashworthy work-zone traffic control devices that are constructed of readily available material. The report will be of particular interest to design, construction, and mainte- nance personnel with responsibility for work-zone safety. The Federal Highway Administration (FHWA) requires that all work-zone traffic control devices used on the National Highway System (NHS) meet the evaluation cri- teria in NCHRP Report 350: Recommended Procedures for the Safety Performance Evaluation of Highway Features. Certain low-mass items, referred to by FHWA as Cat- egory 2 devices, must meet NCHRP Report 350 criteria if they are purchased new or fabricated after October 1, 2000. Category 2 devices include the Manual on Uniform Traffic Control Devices (MUTCD) Type I, II, and III barricades; vertical panels; and temporary sign supports. Many of the designs that meet NCHRP Report 350 criteria are proprietary and can cost considerably more than comparable shop-fabricated designs. Although the shop-fabricated devices in use are made from readily available, low-cost materials, not all designs have been properly crash tested and evaluated to permit their continued use on the NHS. Because all Category 2 work-zone traffic control devices used on the NHS must meet NCHRP Report 350 criteria, a number of nonproprietary, crashworthy work-zone traffic control devices need to be identified or developed and their plans and specifica- tions made available to state transportation agencies. These devices need to be easily fabricated of readily available materials, be cost efficient, and meet NCHRP Report 350 crash test criteria. Under NCHRP Project 22-18, “Crashworthy Work-Zone Traffic Control Devices,” Texas Transportation Institute designed and successfully crash tested two Type III barricades with attached sign panel; three low-mounting-height, portable sign supports; and a high-mounting-height, portable sign support. In Phase I, the research team reviewed the literature and ongoing research to iden- tify Category 2 devices that have been crash tested and conducted a survey of state and federal transportation agencies to obtain information on Category 2 work-zone traffic control devices currently being used. The focus was on identifying widely used sets of devices that have few or no nonproprietary, crashworthy designs. Based on this infor- mation, the panel selected sets of work-zone traffic control devices for investigation under Phase II. In Phase II, the research team developed several design variations for each of the device sets selected in Phase I. The designs were reviewed and prioritized by the pro- ject panel, and the prioritization served as the basis for the full-scale crash testing matrix. In addition to providing detailed drawings and specifications for the success- fully crash tested systems, the report presents a description of the other design concepts for future consideration and testing. FOREWORD By Charles W. Niessner Staff Officer Transportation Research Board

1 CHAPTER 1 Introduction 1.1 Research Problem Statement, 1 1.2 Research Objective, 1 2 CHAPTER 2 Testing Requirements for Work-Zone Devices 2.1 NCHRP Report 350 Guidance, 2 2.2 Categories of Work-Zone Devices, 2 2.3 Test Matrix Modifications, 3 2.4 Impact Conditions, 3 2.5 Evaluation Criteria, 3 5 CHAPTER 3 State of the Practice 3.1 Recent Research and Testing, 5 3.1.1 Barricades, 5 3.1.2 Other Traffic Control Devices, 6 3.2 Manufacturers and Suppliers, 7 3.3 Federal Highway Administration, 7 3.4 State-of-the-Practice Survey, 8 3.5 National Work Zone Safety Information Clearinghouse, 8 9 CHAPTER 4 Design Considerations 4.1 Factors Influencing Crashworthiness, 9 4.2 Functional Design Considerations, 10 4.2.1 Wind Resistance, 10 4.2.2 Durability, 11 4.2.3 Site Adaptability, 11 4.2.4 Environmental Effects, 11 4.2.5 Functional Performance Rating, 11 13 CHAPTER 5 Performance Assessment and Categorization 5.1 Portable Temporary Sign Supports, 13 5.2 Barricades and Barricades with Sign Attachments, 13 5.3 Recommendations for Phase II, 14 16 CHAPTER 6 Barricades with Sign Attachments 6.1 Design Considerations, 16 6.1.1 Sign Substrate, 16 6.1.2 Mounting Height, 16 6.1.3 Barricade Construction, 16 6.1.4 Warning Lights, 17 6.2 Design Alternatives, 17 6.2.1 Perforated Steel Tubing, 17 6.2.2 Hollow-Profile Plastic, 21 6.3 Functional Characteristics, 22 6.4 Prioritization, 22 6.5 Full-Scale Crash Testing, 23 6.5.1 Test 1, 23 6.5.2 Test 2, 28 6.5.3 Test 3, 32 6.5.4 Test 4, 38 45 CHAPTER 7 Low-Mounting-Height Sign Supports with Rigid Sign Substrates 7.1 Design Alternatives, 45 7.1.1 Design L1: Independent Dual Uprights, 46 7.1.2 Design L2: H-Base with Single Upright, 47 7.1.3 Design L3: Pivoting Dual Uprights, 47 7.1.4 Design L4: H-Base with Dual Uprights, 47 7.1.5 Design L5: X-Base with Single Upright, 49 7.1.6 Design L6: X-Base with Pivoting Upright, 49 7.1.7 Design L7: Adjustable Tripod, 50 7.1.8 Design L8: HDPE/Wooden Support, 50 7.1.9 Design Summary, 52 7.2 Prioritization, 52 7.3 Full-Scale Crash Testing, 52 7.3.1 Test 5, 52 CONTENTS

7.3.2 Test 6, 59 7.3.3 Test 7, 63 69 CHAPTER 8 High-Mounting-Height Sign Supports with Rigid Sign Substrates 8.1 Wind Load Analysis, 69 8.1.1 Overturn, 71 8.1.2 Structural Adequacy, 72 8.2 Design Alternatives, 73 8.2.1 Design H1: Dual Uprights with Slip Connection, 73 8.2.2 Design H2: Strong Dual Uprights with Slip Connection, 75 8.2.3 Design H3: Dual Nested Uprights, 75 8.2.4 Design H4: Dual Uprights with Knee Braces, 76 8.2.5 Design H5: Single Upright with Slip Connection, 78 8.2.6 Design H6: Dual Uprights with Raised Slip Joint, 78 8.2.7 Design H7: Dual Three-Piece Uprights, 79 8.2.8 Design H8: Dual HDPE Uprights, 80 8.3 Prioritization, 81 8.4 Full-Scale Crash Testing, 82 8.4.1 Test 8, 84 8.4.2 Test 9, 89 8.4.3 Test 10, 94 100 CHAPTER 9 Findings and Recommendations 9.1 Type III Barricades with Signs, 100 9.1.1 Perforated Steel-Tube Barricades, 100 9.1.2 Hollow-HDPE/Wooden Barricade, 101 9.2 Low-Mounting-Height Sign Supports, 104 9.2.1 Adjustable Tripod, 104 9.2.2 Pivoting Dual Uprights, 104 9.2.3 Independent Dual Uprights, 109 9.3 High-Mounting-Height Sign Supports, 109 9.3.1 Dual Uprights with Slip Connection, 109 9.3.2 Dual Uprights with Raised Slip Joint, 109 9.3.3 Strong Dual Uprights with Slip Connection, 109 9.3.4 Additional Designs, 112 9.4 Functionality, 115 116 REFERENCES 117 APPENDIX A FHWA Windshield Damage Classification 119 APPENDIXES B through F