COLORADO OT . DEPARTMENT OF TRANSPORTATION METRIC CONVERSION MANUAL January 1994 This manual or any part thereof must not be reproduced in any form without the following disclaimer. The information presented in this publication haS been prepared in accordance with recognized engineering principles and is for general information only. While it is believed to be accurate, this information should not be used or relied upon for any specific application without competent professional examination and verification of its accuracy, suitability, and applicability by a competent licensed engineer or other licensed professional. Publication of the material contained herein is not intended as a representation or warranty on the part of the Colorado Department of Transportation (CDOT) , that this information is suitable for any general or particular use or of freedom from infringement of any patent or patents. Anyone making use of this information assumes all liability arising from such use. Caution must be exercised when relying upon the specifications and codes developed by other bodies and incorporated herein, since such material may be modified or amended from time to time subsequent to the printing of this edition. COOT bears no responsibility for such material other than to incorporate it at the time of the initial publication of this edition, subject to the general comments set forth in the preceding paragraph. Table of Contents Preface ................................................... v Introduction . vii Chapter 1: Metric Units, Terms, Symbols, and Conversion Factors . ... 1-1 Basic Metric . 1-1 Length, Area, Volume and Temperature . 1-7 Civil and Structural Engineering . 1-10 Metric Project Definition ....................... .. 1-12 Chapter 2: Right-Of-Way .................................... 2-1 Preliminary Survey . .. 2-1 Design/Plan Preparation ......... ................... 2-5 Utilities . .. .2-6 Acquisition . .2-6 Chapter 3: Roadway Design . 3-1 Drawing Sizes . 3-1 Drawing Scales .......................... 3-2 Units Used on Drawings .......................... 3-2 Elevation and Contour Intervals .. 3-3 Stationing and Cross-Section Intervals .................. 3-3 Angles and Horizontal Curves ...... 3-4 Survey Plotting Accuracy . ~ . 3-8 Proposed Features on Roadway Plans . 3-8 Specifications ................................. 3-9 Cross-Section Elements and Design Data ............... 3-10 Superelevation . .. 3-20 Hydraulics .................................. 3-24 Cost Estimation . 3-30 Chapter 4: Structures . 4-1 Drawing Sizes . 4-2 Drawing Scales ......................... 4-2 Fasteners . 4-3 Units Used on Drawings .......................... 4-3 Units for Structural Steel Design .................... 4-11 AASHTO Expressions. 4-14 Chapter 5: Materials ....................................... 5-1 Units .............................. .. .... 5-1 Structural Steel ................................ 5-2 Steel Fabrication ............................... 5-3 Reinforcing Steel ........................... ... 5-4 Steel Plate ................................... 5-5 Sheet Metal .................................. 5-6 Steel Wire Strand ..... ......................... 5-7 Seven-Wire, Uncoated Strand for Prestressed Concrete Structures ................. .. 5-8 Concrete .................................... 5-8 Sieves ...................................... 5-9 Hard Conversions for Construction Materials . .. 5-11 Chapter 6: Traffic . 6-1 Units ............. ' ......................... 6-1 Sign Conversion Values . 6-1 Sign Conversion Techniques ......... .. ........ .. 6-2 Basic Sign Types ... 6-3 Design Issues .............. '. '. 6-7 Standard Cases and Sign Conversion Details ............. 6-16 Work Zone Signs .......... ................... 6-21 Public Awareness Plan . 6-22 Recommendations . 6-23 Pavement Markings ............................ 6-24 General Process Topics ........................ 6-24 Chapter 7: Maintenance ..................................... 7-1 Maintenance Management System Database . 7-1 Maintenance Management System Activities Units ........... 7-1 Road Equipment and Shops . 7-3 Chapter 8: Planning . '. 8-1 Units ............ ~ ......................... 8-1 Planning ................................... 8-1 Pavement Management Program . 8-1 Intermodal .........•....................... .. 8-2 GIS ....................................... 8-2 Traffic ..................................... 8-2 Field ...................................... 8-2 Data Management ................. ............ 8-2 ii Chapter 9: Environmental .................................... 9-1 Units ...................................... 9-1 Noise Analysis and Leaking . Underground Storage Tank Remediation ...... ....... .... 9-2 Archaeology Unit and Paleontology .................... 9-3 Air Quality Unit ............................... 9-3 Hazardous Waste Unit ............................ 9-3 Biology and Ecology . 9-4 History and Scenic Byways . 9-4 Miscellaneous Environmental Services .................. 9-4 Coordinating the Conversion Process . 9-5 Training and Internal Coordination .................... 9-5 Chapter 10: Computer Systems .................................. 10-1 Computer Geometry (COGO) ...................... 10-2 Graphics · . 10-2 Engineering ................................. 10-3 Hydraulics ...... 10-3 Management Systems ........................... 10-4 Other Systems . 10-5 General References R-1. Dolores Proj ect ............................................ A-I iii iv Preface The United States must commit to metrication. Two overwhelming factors, the adoption of the metric system by the remainder of the world and the changing global economy, mandate that this nation must change. This Guide has been written to provide an explanation of the need for the change, and to serve as a resource to help bridge the gap between building roads in the English-based system of units and the Metric system. It is intended that this guide be used as a reference manual for CDOT employees in the Right-Of-Way, Design, Bridge, Materials, Traffic, Maintenance, Planning, and Environmental areas. The AASHTO Metric Task Force requested that each AASHTO Highway Subcommittee and task force develop a position and recommendations addressing metrication items in their areas of responsibility. The AASHTO committees and task-forces are attempting to address the metrication impacts in all areas of highway transportation. It is possible that different task forces will adopt different criteria for the same items. It may be that as the highway industry begins to use the criteria, they may be revised. Thus, some metric criteria in this guide may require change at a later date. The reader is advised to seek the most recent version of AASHTO policy on these issues. v vi I ntrodu ction The United States is converting its transportation system to the metric system; and the date that the Federal Highway Administration has established is September 30,1996. After that date, no highway projects may be paid for with Federal Lands Highway or Federal-aid Highway funds unless the plans, specifications and estimate (PS&E) are all in metric units. LEGAL BASIS FOR HIGHWAY CONVERSION Metric Conversion Act of 1975 & Omnibus Trade and Competitiveness Act of 1988 The impetus for the change came from Congress. The Metric Conversion Act of 1975 encouraged metrication, but left it as a voluntary activity. As a consequence, virtually no metrication took place. The Omnibus Trade and Competitiveness Act of1988 amended the 1975 Act to designate the modern metric system (System International or SI) as the preferred system of weights and measures for U.S. trade and commerce. It also requires each federal agency to convert to metric, and requires each federal agency to use metric in its procurements, grants, and other business-related activities to the extent economically feasible. These acts did not mandate that individual states, cities, counties, industries, or other organizations convert to metric. However, these entities cannot obtain federal roadway money unless they use metric. It is probable that all will convert to metric to remain eligible for road funds, and it is best that we all convert quickly using consensus guidelines. Executive Order 12770 In addition to the congressional legislation, Executive Order 12770 was issued in July 1991. It required each federal agency to adopt a metric conversion plan by November 30,1991. Among the other provisions of the executive order were instructions that the Department of Commerce was to lead the metrication effort. The Federal Highway Administration Metric Transition Plan was approved by the Secretary of Transportation in October 1991. It laid out procedures and administrative policies for the conversion, and established certain milestone dates. For example, after September 30, 1992, FHWA publications and correspondence were to use metric as the primary system of units for all measurements. FHWA manuals and documents were to be systematically revised and republished in metric so they would be available to guide the conversion. The key date is September 30, 1996. All construction contracts advertised for bids after that date must contain only metric measurements for any federal lands highway or federal-aid highway construction project. vii u.s. DOT Metric Conversion Planning Guidelines On May 8,1990, the u.s. Department of Transportation (U.S. DOT) issued Order 1020.1C which established policy and administrative procedures for the transition. A change to the