1c HIGHWAYRESEARCH BOARD Special Report 61C The. AA.SHO Road Test Report 3 7 TrOTTIC Operations and Pavement Maintenance HIGHWAY RESEARCH 'BOARD Officers and Members of 'the Executive Committee 1962 OFFICERS. R. R. BARTELSMEYER, Chairman C. D. CURTISS, First Vice Chairman WILBUR S. SMITH, Second Vice Chairman FRED BURGGRAF,' Director WILLIAM N. CAREY, JR., Assistant Director Executive Committee REx M. WHITTON, Federal Highway Administrator, Bureau of Public Roads (ex officio) A: E. JOHNSON, Executive Secretary, American Association of State Highway Officials (ex officio) Louis JORDAN, Executive Secretary, Division of Engineering and Industrial Research, National Research Council (ex officio) PYKE JOHNSON, Retired (ex officio, Past Chairman 1960) W. A. BUGGE, Director of Highways, Washington Department of Highways (ex officio, Past Chairman 1961) R. R. BARTELSMEYER, Chief Highway Engineer, Illinois Division of Highways E. W. BAUMAN, Director, National Slag Association, Washington, D. C. - DONALD S. BERRY, Professor of Civil Engineering, Northwestern University MASON A. BUTCHER, County Manager, Montgomery County, Md. J. DOUGLAS CARROLL, JR., Director, Chicago Area Transportation Study C. D. CuRnss, Special Assistant to the Exeutive Vice President, American Road Builders' Association HARMER E. DAVIS, Director, Institute of Transportation and Traffic Engineering, Uni- versity of California DUKE W. DUNBAR, Attorney General of Colorado MICHAEL FERENCE, JR., Executive Director, Scientific Laboratory, Ford Motor Company D. C. GREER, State Highway Engineer, Texas State Highway Department JOHN T. HOWARD, Head, Department of City and Regional Planning, Massachusetts Institute of Technology BURTON W MARSH, Director, Traffic Engineering and Safety Department, American Automobile Association OSCAR T. MARZKE, Vice President, Fundamental Research, U. S. Steel Corporation B. MCMORRAN, Superintendent of Public Works, New York State Department of Public Works CLIFFORD F. RASSWEILER, Vice President for Research and Develop?nent, Jóhns-Manville Corporation GLENN C. RICHARDS, Co?nmissioner, Detroit Department of Public Works C. H. SCHOLER, Applied Mechanics Department, Kansas State University WILBUR S. SMITH, Wilbur Smith and Associates, New Haven, Conn. B. WOODS, Head, School of Civil Engineering, and Director, Joint Highway Research Project, Purdue University Editorial Staff FRED BURGGRAF HERBERT P. ORLAND EARLE W. JACKSON -. 2101 Constitution Avenue Washington 25, D. C. The AASHO Road Test Report 3 Traffic Operations and Pavement Maintenance By the HIGHWAY RESEARCH BOARD ofthe NAS-NRC Division of Engineering and Industrial Research Special Report 61C Publication No. 952 National Academy of Sciences—National Research Council Washington, D.C. 1962 This is one of a series of reports of work done under a fiscal agreemeht of June 10, 1955, between the National Academy of Sciences and the Bureau of Public Roads relating to AASHO Road Test Project; and under individ- ual agreements covering Cooperative Highway Research Project (AASHO Road Test) made between the National Academy of Sciences and the several participating state highway departments, members of the Ameri- can AssocIation of State Highway Officials. Included in the series are the following reports: HRB Special Report Subject Report No. 1 History and Description of Project 61A 2 Materials and Construction 61B 3 Traffic Operations and Pavement Maintenance 61C 4 Bridge Research 61D 5 Pavement Research filE 6 Special Studies 61F 7 Final Summary 61G Available from the Highway Research Board National Academy of Sciences— National Research Council Washington 25, D. C. Library of Congress Catalog Card No. 61-60063 11 NATIONAL ADVISORY COMMITTEE This committee was appointed by the Highway Research Board to advise the Board and its project staff in relation to administrative and technical matters. K. B. Woods, Chairman Head, School of Civil Engineering, and Director, Joint Highway Research Project, Purdue University W. A. Bugge, Vice-Chairman Director, Washington Department of Highways W. F. Abercrombie,' Engineer of Materials and J. B. Hulse, Managing Director, Truck Trailer Tests, Georgia State Highway Department Manufacturers Association R. R. Bartelsmeyer, Chairman, AASHO Com- F. N. Hveem, Materials and Research Engi- mittee on Highway Transport, and Chief neer, California Division of Highways Highway Engineer, Illinois Division of A. E. Johnson, Executive Secretary, American Highways; Chairman, Highway Research Association of State Highway Officials Board 2 M. S. Kersten, Professor of Civil Engineering, W. G. Burket, Tire Industry; Chairman, Tech- University of Minnesota nical Advisory Committee, Rubber Manu- facturers Association;3 Manager, Truck George Langsner, Chairman, AASHO Commit- Tire Engineering, Goodyear Tire and tee on Design; Assistant State Highway Rubber Company Engineer, California Division of Highways H. M. Straub,4 Tire Industry; Manager, Tire R. A. Lill,7 Chief, Highway Engineering, Construction and Design, B. F. Goodrich American Trucking Associations Company George Egan, 5 Chief Engineer, Western K. Chacey, Director of Transportation Highway Institute Engineering, Office of the Chief of Trans- R. E. Livingston, Planning and Research Engi- portation, Department of the Army Trans- neer, Colorado Department of Highways portation Corps L. C. Lundstrom, Former Chairman, Automo- W. E. Chastain, Sr., Engineer of Physical Re- bile Manufacturers Association Committee search, Illinois Division of Highways for Cooperation with AASHO Road Test; R. E. Fadum, Head, Civil Engineering Depart- Director, General Motors Proving Ground ment, North Carolina State College T. F. Creedon,*s Highway Engineering Ad- A. Finney, Director, Research Laboratory, viser, Automobile Manufacturers Associa- Michigan State Highway Department tion C. E. Fritts, Vice-President for Engineering, G. W. McAlpin,9 Assistant Deputy Chief Engi- Automotive Safety Foundation neer (Research), New York State Depart- R. H. Winslow, * Highway Engineer, Automo- ment of Public Works tive. Safety Foundation B. W. Marsh, Director, Traffic Engineering and Sidney Goldin, Petroleum Industry; General Safety Department, American Automobile Manager, Head Office Marketing, Shell Oil Association Company R. A. Moyer, Professor of Highway Transpor- J. 0. Izatt,* Petroleum Industry; Asphalt tation Engineering, and Research Engi- Paving Technologist, Products Application neer, Institute of Transportation and Department, Shell Oil Company Traffic Engineering, University of Cali- W. D. Hart,5 Transportation Economist, Na- fornia tional Highway Users Conference R. L. Peyton, Assistant State Highway Engi- E. H. Holmes, Assistant Commissioner for Re- neer, Kansas State Highway Commission search, Bureau of Public Roads K. M. Richards, Manager, Field Services De- C. F. Rogers,* Special Assistant, Office of Re- partment, Automobile Manufacturers As- search, Bureau of Public Roads sociation 111 John H. King,* Manager, Motor Truck Divi- H. 0. Thompson, Testing Engineer, Mississippi sion, Automobile Manufacturers Associa- State Highway Department tion J. C. Womack, President, American Association of State Highway Officials ;'° State High- T. E. Shelburne, Director, Highway Investiga- way Engineer and Chief of Division of tion and Research, Virginia Department Highways, California Division of High- of Highways ways The following persons served on the National Advisory Committee dur- ing the years indicated in the same capacity as the current member bearing the same footnote indicator: 1 J• L. Land, Chief Engineer, Bureau of Materials and A. A. Anderson, Chief Highway Consultant, Portland Tests, Alabama State Highway Department (1956) Cement Association (1956-1960) Hugh Barnes, Assistant Vice-President, Portland 2 C. H. Scholer (1958); H. E. Davis (1959); Pyke Johnson (1960); W. A. Bugge (1961)—Chairman, Cement Association (Resigned March, 1961) McHenry,* Highway Research Board Douglas Portland Cement Association (1956) 3 G. M. Sprowls (1956); C. R. Case (1957); W. C. Earl J. Felt,* Portland Cement Association (1957- Johnson (1958); Louis Marick (1959); H. M. Straub 1960) (1960) B. E. Colley,* Portland Cement Association (Re- Louis Marick (1960) signed March, 1961) 'R. E. Jorgensen, Engineering Counsel, National H. F. Clemmer, Consultant, D. C. Department of High- Highway Users Conference (1956-1961) ways and Traffic (1956-1960) ° J. C. Young (1956); C. A. Weber (1957-1959); J. C. W. C. Hopkins, Deputy Chief Engineer, Maryland State Womack (1960) Roads Commission (1956-1961), R. D. Johnson,* Assistant Engineering Counsel, Na- 7 H. A. Mike Flanakin, Highway Engineer, American Trucking Associations (1956-1957) tional Highway Users Conference (1958-1961) 8 A. S. Wellborn, Chief Engineer, The Asphalt Institute I.E. Johnson, Manager, Chrysler Corporation Prov- (1956—Resigned March, 1961) ing Ground (1956-1960) J. M. Griffith,* Engineer of Research, The Asphalt L. K. Murphy, Construction Engineer, Primary Institute (1956—Resigned March, 1961) Highways, Maine State Highway Commission (1956- Rex M. Whitton, First Vice-Chairman (1956-1961); 1959) Chief Engineer, Missouri State Highway Depart- 10 C. R. McMiIIan (1958); D. H. Stevens (1960); D. H. ment. Resigned March 1961 to become Federal Bray (1961) Highway Administrator W. C. Williams, State Highway Engineer, Oregon State Highway Commission (1956-1961) * Alternate iv Preface The AASHO Road Test was conceived and materials and the construction of the test sponsored by the American Association of facilities.