Tai Lieu Chat Luong Traffic and Highway Engineering FOURTH EDITION Nicholas J Garber Lester A Hoel University of Virginia Australia • Brazil • Japan • Korea • Mexico • Singapore • Spain • United Kingdom • United States Traffic and Highway Engineering, Fourth Edition Nicholas J Garber and Lester A Hoel Director, Global Engineering Program: Chris Carson Senior Developmental Editor: Hilda Gowans Permissions: Natalie Barrington Production Service: RPK Editorial Services, Inc Copy Editor: Shelly Gerger-Knechtl Proofreader: Martha McMaster © 2009 Cengage Learning ALL RIGHTS RESERVED No part of this work covered by the copyright herein may be reproduced, transmitted, stored or used in any form or by any means graphic, electronic, or mechanical, including but not limited to photocopying, recording, scanning, digitizing, taping, Web distribution, information networks, or information storage and retrieval systems, except as permitted under Section 107 or 108 of the 1976 United States Copyright Act, without the prior written permission of the publisher Indexer: Shelly Gerger-Knechtl Creative Director: Angela Cluer Text Designer: RPK Editorial Services Cover Designer: Andrew Adams Cover Image: (to come) For product information and technology assistance, contact us at Cengage Learning Customer & Sales Support, 1-800-354-9706 For permission to use material from this text or product, submit all requests online at cengage.com/permissions Further permissions questions can be emailed to permissionrequest@cengage.com Compositor: G&S/Newgen Printer: Thomson West Library of Congress Control Number: 2008926026 ISBN-13: 978-0-495-08250-7 ISBN-10: 0-495-08250-3 Cengage Learning 1120 Birchmount Road Toronto ON M1K 5G4 Canada Cengage Learning is a leading provider of customized learning solutions with office locations around the globe, including Singapore, the United Kingdom, Australia, Mexico, Brazil, and Japan Locate your local office at: international.cengage.com/region Cengage Learning products are represented in Canada by Nelson Education Ltd For your course and learning solutions, visit academic.cengage.com Purchase any of our products at your local college store or at our preferred online store www.ichapters.com Printed in the United States of America 11 10 09 08 This book is dedicated to our wives, Ada and Unni and to our daughters, Allison, Elaine, and Valerie and Julie, Lisa, and Sonja With appreciation for the support, help, and encouragement that we received during the years that were devoted to writing this textbook This page intentionally left blank Contents P A R T 䊏 INTRODUCTION The Profession of Transportation Importance of Transportation Transportation History Transportation Employment Summary 23 Problems 24 References 25 3 16 Transportation Systems and Organizations Developing a Transportation System Modes of Transportation 34 Transportation Organizations 47 Summary 51 Problems 52 References 54 27 P A R T 䊏 TRAFFIC OPERATIONS 27 55 Characteristics of the Driver, the Pedestrian, the Vehicle, and the Road 57 Driver Characteristics 58 Perception-Reaction Process 60 Older Drivers’ Characteristics 61 Pedestrian Characteristics 62 Bicyclists and Bicycles Characteristics Vehicle Characteristics 63 Road Characteristics 88 62 v vi Contents Summary Problems References 93 95 98 Traffic Engineering Studies Spot Speed Studies 100 Volume Studies 115 Travel Time and Delay Studies Parking Studies 139 Summary 146 Problems 147 References 150 Highway Safety 99 133 151 Issues Involved in Transportation Safety Strategic Highway Safety Plans 154 Effectiveness of Safety Design Features Summary 208 Problems 208 References 212 152 190 Fundamental Principles of Traffic Flow 213 Traffic Flow Elements 213 Flow-Density Relationships 218 Shock Waves in Traffic Streams 230 Gap and Gap Acceptance 243 Introduction to Queuing Theory 249 Summary 258 Problems 258 Intersection Design 265 Types of At-Grade Intersections 266 Design Principles for At-Grade Intersections Design of Railroad Grade Crossings 314 Summary 320 Problems 322 References 325 Intersection Control 276 327 General Concepts of Traffic Control 327 Conflict Points at Intersections 331 Types of Intersection Control 332 Signal Timing for Different Color Indications Freeway Ramps 373 Summary 378 Problems 378 References 380 342 Contents Capacity and Level of Service for Highway Segments Two-Lane Highways Freeways 406 Multilane Highways Summary 430 Problems 431 References 434 Appendix: Tables 10 382 424 434 Capacity and Level of Service at Signalized Intersections Definitions of Some Common Terms 457 Level of Service at Signalized Intersections Summary 528 Problems 528 References 533 Appendix: Tables 534 460 PART 䊏 TRANSPORTATION PLANNING 11 381 The Transportation Planning Process 549 551 Basic Elements of Transportation Planning Transportation Planning Institutions 562 Urban Transportation Planning 566 Forecasting Travel 574 Summary 586 Problems 587 References 588 12 Forecasting Travel Demand 552 591 Demand Forecasting Approaches 591 Trip Generation 593 Trip Distribution 603 Mode Choice 613 Traffic Assignment 625 Other Methods for Forecasting Demand Estimating Freight Demand 637 Traffic Impact Studies 638 Summary 644 Problems 645 References 652 13 Evaluating Transportation Alternatives Basic Issues in Evaluation 653 Evaluation Based on Economic Criteria Evaluation Based on Multiple Criteria Summary 684 Problems 684 References 689 633 653 657 669 457 vii viii Contents P A R T 䊏 LOCATION, GEOMETRICS, AND DRAINAGE 14 Highway Surveys and Location 691 693 Principles of Highway Location 693 Highway Survey Methods 701 Highway Earthwork and Final Plans 723 Summary 731 Problems 733 References 734 15 Geometric Design of Highway Facilities 737 Factors Influencing Highway Design 738 Design of the Alignment 754 Special Facilities for Heavy Vehicles on Steep Grades Bicycle Facilities 791 Parking Facilities 796 Computer Use in Geometric Design 801 Summary 802 Problems 802 References 805 16 Highway Drainage 790 807 Surface Drainage 807 Highway Drainage Structures 809 Sediment and Erosion Control 811 Hydrologic Considerations 813 Unit Hydrographs 826 Hydraulic Design of Highway Drainage Structures Subsurface Drainage 870 Economic Analysis 889 Summary 889 Problems 889 References 891 Additional Readings 892 P A R T 䊏 MATERIALS AND PAVEMENTS 17 Soil Engineering for Highway Design Soil Characteristics 895 Basic Engineering Properties of Soils Classification of Soils for Highway Use Soil Surveys for Highway Construction Soil Compaction 922 Special Soil Tests for Pavement Design Frost Action in Soils 936 Summary 937 Problems 937 References 914 827 893 895 899 907 917 932 Contents 18 Bituminous Materials 943 Sources of Asphalt 943 Description and Uses of Bituminous Binders Properties of Asphalt Materials 949 Tests for Asphalt Materials 953 Asphalt Mixtures 969 Superpave Systems 992 Summary 1019 Problems 1019 References 1022 19 Design of Flexible Pavements 1025 Structural Components of a Flexible Pavement Soil Stabilization 1027 General Principles of Flexible Pavement Design Summary 1070 Problems 1070 References 1073 20 Design of Rigid Pavements 946 1025 1032 1075 Materials Used in Rigid Pavements 1076 Joints in Concrete Pavements 1081 Types of Rigid Highway Pavements 1083 Pumping of Rigid Pavements 1084 Stresses in Rigid Pavements 1085 Thickness Design of Rigid Pavements 1093 Summary 1129 Problems 1129 References 1131 21 Pavement Management 1133 Problems of Highway Rehabilitation 1133 Methods for Determining Roadway Condition Pavement Condition Prediction 1151 Pavement Rehabilitation 1160 Pavement Rehabilitation Programming 1162 GIS and Pavement Management 1172 Summary 1174 Problems 1174 References 1176 Appendixes Index 1207 1177 1136 ix Index temperature effects on, 950 –952 tests for, 953 –968 thin-film oven (TFO) test for, 960 –961 volatilization of, 950, 966 volume of, 950 water content test for, 967 water resistance of, 952 weathering, 950 –951, 960 –961 Asphalt binders, 993 –1002, 1017, 1009 –1001, 1017–1018 grades, 996 –1002 selection of, 993 –999 superpave systems, in, 9993 –1002, 1017 traffic speed and loading considerations for, 1000 –1002 volumetric trial mixture design, 1009 –1018 Asphalt cutbacks, 947, 951–952, 954 –955, 961–962 distillation test for, 961–962 medium-curing (MC) asphalts, 947, 956 process for and use of, 947 rapid-curing (RC) asphalts, 947, 955 rate of curing for, 951–952, 961–962 slow-curing (SC) asphalts, 947 Asphalt Institute (AI), 50 Asphalt mixtures, 969 –992 adjustments of, 981–989 aggregates and, 969 –974, 976 –978 air voids, percent of in compacted, 980 –981 asphalt content of, 974 –975, 979 –980 coats for, 991 cold-mix, cold-laid, 990 –992 evaluation of design, 981–989 gradation of aggregates for, 969 –974 hot-mix, cold-laid, 989 hot-mix, hot-laid, 969-989 Marshall methods for, 974 –976 paving, 969 –971, 979 seals for, 990 specific gravity calculations for, 976 –979 stability test for, 975 –981 surface treatments for, 991–992 voids in, 980 –982 Association of American Railroads, 50 At-grade intersections, 265 –301 alignment of, 276 –277 channelization of, 285 –294 curves at, 278 –285 interchanges compared to, 265 –266 pavement widths of turning roadways at, 294 –301 profile (vertical alignment) of, 277–278 roundabouts, 271–275 traffic circles, 271–275 traffic islands, 285 –294 types of, 266 –273 Atterberg limits, 904 –907 liquid (LL), 904 –905 liquidity index (LI), 905 –906 permeability (K), 906 plastic (PL), 904 shear strength (S), 906 –907 shrinkage (SL), 904 Automated data processing systems (ADP), 99 Automatic method for volume counts, 117–121 1209 Automobiles, 8, 14 –15, 28 –29 See also Vehicles history of, 8, 14 –15 selection of transportation by, 28 –29 Autoscopes, 106 –108 Average daily traffic (ADT), 115, 742 –743 Average end-area method for earthwork, 724 –276 Average growth factor model, 613 Average speed, 101, 114 –115, 134 –135, 418 – 424, 428 – 430 comparison of, 114 –115 mean, calculation of, 101 spot speed studies, 101, 114 –115 standard deviation of, 102 –104, 114 –115 travel time and delay studies, 134 –135 Average travel speed (ATS), 383, 389 –392, 397– 400, 402 – 406, 418 – 424, 428 – 430 adjustment factors (f) for, 389 –390, 419 – 420, 439 base free-flow speed and, (BFFS), 390 directional segments, 397– 400, 402 – 406 downgrades, 398 – 400 free-flow (FFS) speed and, 389 –390, 418 – 420, 428 – 430 freeway sections, 418 – 424 multilane highways, 428 – 430 passing lanes, 400 – 405 two-lane highways, 383, 389 –392, 397– 400, 402 – 406 two-way segments, 389 –392 upgrades, 397– 400 Aviation, 8, 28 –29, 34 –36 freight traffic by, 34 –36 history of, passenger traffic by, 34 –36 selection of transportation by, 28 –29 B Backfill material for longitudinal collectors, 889 Backward shock waves, 231–233 Backwater curve of channel flow, 836 Balance-sheet approaches for evaluation, 678 – 679 Barricades to ramps, 374 Barriers, 286, 374, 748 curbs, 286 cross sections for geometric design, 748 ramps, to, 374 Base course for pavement design, 1026, 1041 Base free-flow speed (BFFS), 390 Beginning of vertical curve (BVC), 764 –770 Bending creep test, 963 Bending stresses, rigid pavements, 1085 –1087 Benefit-cost ratio (BCR) method of evaluation, 666 Bevel-edged inlets, 866 – 867 Bicycle occupancy (OCCbicg), 483 – 488 Bicyclists, 62 – 63, 699 –700, 791–797 alignment of paths, 795 –797 characteristics of for traffic, 62 – 63 design speed for, 795 geometric design of facilities for, 791–797 lanes for, 792 –793 paths for, 793 –797 provisions for in urban locations, 699 –700 Bituminous binders, 946 –949 asphalt cements, 946 asphalt cutbacks, 947 1210 Index Bituminous binders (continued) emulsified asphalts, 947–948 blown asphalt, 948 –949 road tars, 949 Bituminous materials, see Asphalt Blankets for drainage, 873 – 875 Bleeding of pavement surface, 1146 Block cracking, 1146 Blown asphalt, 948 –949, 959 –960 process for and use of, 948 –949 ring-and-ball softening point test for, 959 –960 Bottleneck conditions, 230 –233 Braking distance (Db), 78 – 85, 88 – 89 friction coefficient for, 80 road characteristics for, 88 – 89 stopping sight distance (S), 81– 83, 88 – 89 vehicle estimation of, 78 – 85 velocity estimates for, 83 – 85 Bridges, 700 –701, 809 – 810 locations of for highway design, 700 –701 surface drainage and, 809 – 810 Brush barriers, 813 Bulk soil density (g), 901–902 Bureau of Transportation Statistics, 6, 34 Bus blockage adjustment factor (fbb), 470 Buses, intercity transportation and, 46 Butt joints, 1083 C Calibration, 233 –237, 583 –584, 604 – 608, 622 – 624, 707 F values in gravity models, 604 – 608 global positioning systems (GPS), 707 macroscopic approach using, 220 –228 traffic flow models, 223 –227 travel forecasting using, 583 –584, 604 – 608, 622 – 624 trip distribution and, 604 – 608 utility functions with survey data, 622 – 624 California Bearing Ratio (CBR) test, 932 –934, 1032 California method of design, 1053 –1056 flexible pavement, 1053 –1056 traffic index (TI) for, 1053 grade equivalent (GE) for, 1053 –1054 Canals, historical development of, 7, 10 Capacity, 36 –37, 381–547 critical flow ratio (v/c) analysis for, 490 – 495 critical lane groups, 492 – 493 flow ratio (v/s) for, 458 – 460 freeways, 406 – 424 level of service (LOS) and, 36 –37, 381–547 multilane highways, 424 – 430 planning level analysis for, 383, 516 –527 public transportation, 36 –37 saturation flow rate (s) for, 458 – 460, 468 – 490 signalized intersections, 457–547 tables for, 539 –541 two-lane highways, 382 – 406 Categorical exclusion (CA), 572 Cement, 946, 1027, 1029 –1031, 1076 –1077 AASHTO specifications for, 1076 –1077 asphalt, 946 compacting mixture of, 1030 curing mixture of, 1031 flexible pavement design using, 1027, 1029 –1031 mixing of soil and, 1029 –1030 plant mixing, 1029 Portland, 1076 –1077 rigid pavement design using, 1076 –1077 road mixing, 1029 soil stabilization using, 1027, 1029 –1031 Central business district (CBD), 122, 139 –140 cordon counts in, 122 parking studies in, 139 –140 Centroids, highway systems, 576 –577 Change and clearance interval, 343, 458 Channelization, 285 –294, 335 See also Traffic Islands at-grade intersection design and, 285 –294 traffic control use of, 335 Channelized traffic islands, 286 –288 Channels, 808 – 809, 812, 828 – 843 backwater curve of flow, 836 cross section for, 836 – 838 erosion control and, 812, 828 highway surface drainage using, 808 – 809, 812, 828 – 843 hydraulic jump in flow, 835 linings, 812, 828 – 829, 838 – 843 longitudinal, 808 – 809, 812 Manning’s formula for, 829 – 834 open, 828 – 843 rapid flow in, 832, 835 steady flow in, 830, 832 tranquil flow in, 832 uniform flow in, 832 Charged coupled device (CCD) arrays, 718 Check dams, 813 Chemical soil weathering, 896 Circular curves, 85 – 88 Citizens’ advisory committee, 563 Civil Aeronautics Board (CAB), 48 Clay (C), 911–912 Cleveland open-cup test, 966 –967 Climbing lanes, 790 –791 Closure of ramps, 374 Cluster analysis of crashes, 164 Coarse aggregates, 1078 Coarse-textured soils, 896, 911–912 Coats for asphalt mixtures, 991 Cold-mix, cold-laid asphalt, 990 –992 Collector street systems, 740 –741 Collectors for drainage, see Longitudinal collectors Collision diagrams, 160 –161 Color vision, 59 Comfort criterion for sag vertical curves, 761, 1205 Commodity flow data, 637– 638 Composite grades, 415 – 418 Compound curves, 778 –781 Computer Aided Design Drafting (CAD), 705 Computer graphics, 717–723 aerial photographs for, 718 airborne GPS (ABGPS), 718 –719 Geographic Information Systems (GIS) for, 20, 579 –581, 722 –723 highway locations determined using, 717–723 Light Detection and Ranging (LiDAR) technology for, 719 –721 Index Computer programs, 801, 827, 864 – 866 culvert design, 864 – 866 geometric highway design, 801 hydrological, 827 models for drainage simulations, 827 Concrete pavement, 1103, 1109 –1121 American Concrete Pavement Association design method for, 1109 –1121 erosion analysis for, 1112 –1121 fatigue analysis for, 1111–1121 flexural strength of, 1109 load safety factor (LSF) for, 1110 properties for rigid pavement, 1103 subbase support for, 1109 subgrade support for, 1109 traffic load determination, 1109 –1110 Condition assessment for pavement rehabilitation, 1163 –1165 Conflict zones, 483 – 487 Consistency of asphalt, 949 –950, 953 –958 float test for, 958 –959 kinematic viscosity test for, 956 –957 penetration test for, 958 –959 rotational viscosity test for, 958 Saybolt Furol Viscosity test for, 953 –956 specified temperatures for, 950 temperature susceptibility, 950 Construction joints, 1083 Consumer surplus, 658 – 659 Continuing costs, 659 – 660 Continuously Reinforced Concrete Pavement (CRCP), 1084 Contraction joints, 1082 Control coefficients for culvert inlets, 848 – 849 Control devices, 327–380 channelization of intersections, 335 concepts of for traffic, 327–331 conflict points of, 331–332 freeway ramps, 373 –377 intersections, 327–380 meters, 375 –377 multiway stop signs, 334 –335 signal timing, 342 –372 stop signs, 334 traffic signals, 335 –372 yield signs, 333 Control points of aerial photographs, 709 Controller for signal timing, 342 –343 Converters for blown asphalts, 948 –949 Coordinated signal system (warrant 6) traffic volume, 340 Cordon (volume) counts, 122 Corrugation of pavement, 1146 Cost effectiveness method of evaluation, 673 – 676 Costs of transportation, –5, 30 –33, 42 – 43, 189, 569 –570, 657– 663 See also Economic evaluations benefits, 660 – 661 consumer surplus, 658 – 659 continuing, 659 – 660 crash (accident), 662 – 663 crash severity and, 189 economic growth and, equilibrium of, 32 –33 estimation, 569 –570 evaluation based on, 657– 669 1211 first, 659 highways, source of funds for, 42 – 43 planning-level estimation, 569 –570 project priorities and, 189 salvage value, 660 social benefits and, –5 sunk, 660 supply and demand for, 30 –33 travel time, 661– 662 vehicle operating, 661 Cracking, 1059, 1066 –1069, 1122 –1128, 1141–1146 alligator (bottom-up), 1059, 1066, 1146 block, 1146 concrete pavement, 1122 –1128 Cumulative Damage Index (DI) for, 1067–1068 distress (defect) rating (DR) for, 1142, 1144 –1146 flexible pavement, 1059, 1066 –1069 joint spalling, 1128 load-related, 1066 longitudinal (top-down), 1066 –1067, 1146 mean transverse joint faulting, 1125 –1128 Mechanistic-Empirical Pavement Design (MEPD) and, 1059, 1066 –1069 non-load-related, 1068 pavement condition index (PCI) for, 1146 pavement distress, 1141–1146 slabs, 1122 –1125 transverse, 1122 –1128 traverse, 1059, 1146 Crash experience (warrant 7) traffic volume, 340 Crash modification factor (CMF), 187 Crash reduction factor (CRF), 187–189 Crashes, 152 –154, 154 –190, 662 – 663 accidents compared to, 152 analysis of data from, 160 –177 causes, identification of, 181–184 cluster analysis of, 164 collision diagrams, 160 –161 contributing circumstances of, 176 costs, 662 – 663 critical crash rate (CR) method for, 177–179 data collection and maintenance for, 155 –159 data storage and retrieval, 156 –160 direct comparisons of, 160 –163 Empirical-Bayes method for, 165, 173 –175 engineering studies for, 181, 183 –189 environmental conditions during, 176 –177 expected value (EV) analysis of, 163 –164 hazardous locations and elements, identification of, 177–181 Highway Safety Improvement Program (HSIP), 155 –190 hypothesis testing for, 165 improvement implementation and evaluation, 190 Kruskal-Wallis H test for, 165, 170 –173 number of, direct comparison of, 160 –161 patterns, 163 –165 potential for safety improvement (PSI) method for, 179 –181 project priorities for avoidance of, 189 proportionality test for, 165, 168 –170 rate per million of entering vehicles (REMV) for, 161–163 severity of, 176, 189 statistical comparisons of, 165 –175 Strategic Highway Safety Plan (SHSP), 154 –190 1212 Index Crashes (continued) summarizing data for, 175 –177 time period of, 177 t-test for, 165 –168 types of, 176 Crest vertical curves, 756 –760, 763 –770 Critical crash rate (CR) method for hazardous locations, 177–179 Critical flow ratio (v/c) analysis, 490 – 495 Critical gap (tc), 244 –246 Critical lane groups, 344, 492 – 493 Critical values of X2, 1177–1180 Cross-classification for trip generation, 594 – 600 Cross sections, 195 –200, 723 –726, 745 –753, 836 – 838 barriers, 748 channel design for, 836 – 838 cross slopes, 750 –752 curbs, 748, 751 earthwork, 723 –726 geometric design and, 745 –753 guard rails, 749 gutters, 748 –749 highway facility elements and, 745 –753 lane width, travel lanes, 746 medians, 747–748 multilane highways, 746 right of way, 753 safety design of, 195 –200 shoulders, 746 –747 side slopes, 752 –753 sidewalks, 749 –750 two-lane highways, 745 Culvert Design System (CDS), 827 Culverts, 810 – 811, 844 – 870 computer programs for, 864 – 866 design of, 844 – 870 economic analysis of, 844 highway structure of, 810 – 811 hydraulic design of, 845 – 864 hydrologic considerations for, 844 inlets, 845 – 852, 866 – 870 location of, 844 outlets, 845, 853 – 864 tailwater, 844 – 845 upstream storage of, 845 Cumulative Damage Index (DI), 1067–1068 Cumulative distribution, 112 –113 Curbs, 286, 291–294, 748, 751, 809, 812 barrier, 286 cross sections for geometric design, 748, 751 erosion control using, 812 mountable, 286 shoulders and design of, 291–294 surface drainage and, 809, 812 traffic islands, 286, 291–294 Curing, 947, 951–952, 1031 asphalt, 947, 951–952 cutback, rate of for, 951–952 emulsions, rate of for, 952 fluxing, 947 soil-cement mixture, 1031 Curve resistance (Rc), 76 Curve templates, 696 – 697 Curves, 85 – 88, 278 –285, 756 –787, 1023 –1025 See also Alignment at-grade intersections, design for, 278 –285 circular, 85 – 88 compound, 778 –781 crest, 756 –760, 763 –770 edge-of-pavement minimums for, 281–284 geometric design of alignment using, 756 –787 metric conversions for equations for, 1023 –1025 minimum radius of, 85 – 88, 1203 parabolic, 756 –757 reverse, 781–783 sag, 756, 760 –770 side friction (fs), coefficients of, 87– 88 simple, 771–777 spiral, 771, 783, 785 –786 superelevation (a), rate of, 85 – 86, 783 –787 transition, 771, 783 –785 vehicle design for, 85 – 88, 279 –280 Cutbacks, see Asphalt cutbacks Cycle length, 343, 349 –360, 365 –368 actuated traffic signals, 365 –368 green time methods for, 351–352 highway capacity method for, 355 –360 pretimed (fixed) traffic signals, 349 –360 total lost time method for, 350 Webster method for, 350, 352 –355 D Daily expansion factors (DEF), 131 Data collectors for digital surveys, 705 Decision sight distance, 89 –90, 1205 Degrees of freedom (v), 128 –129 Delay, 133, 362 –365, 494, 496 –500 approach, 498, 500 incremental, 494, 496 intersection, 500 level of service (LOS) and, 494, 496 –500 performance measures module, 494, 496 –500 protected-plus permitted options, with, 497– 499 residual demand, 496 signal time, 362 –365 total control, 496 – 497 travel-time, 133 types of, 133 uniform, 494, 497– 499 Delay studies, see Travel time and delay studies Demand flow rate, 466 – 468 Demand forecasting, see Travel demand forecasting Demulsibility test for asphalt emulsions, 967–968 Density, 214, 218 –219, 418 – 424, 901–902 bulk (g), 901–902 dry (gd), 901 flow and, relationship between, 218 –219 freeway sections, 418 – 424 jam (kj), 219 soil, 901–902 submerged (g), 901 total (g), 901–902 traffic (k), 214, 218 –219, 421– 422 Department of Agriculture, Trade, and Consumer Protection (DATCP), 40 Index Departure sight, 301–302 Depressions in pavement, 1146 Depth perception, 59 – 60 Design for transportation, see Geometric design Design hourly volume (DHV), 344, 346 –347, 742 –743 average daily traffic (ADT) and, 742 –743 geometric design and, 742 –743 peak-hour factor (PHF) for, 344, 346 –347 signal timing and, 344, 346 –347 Design speed, see Speed Design vehicle, see Vehicles Destructive (cracking) distillation of petroleum asphalt, 946 Destructive methods for soil compaction, 928 –929 Deterministic models for pavement condition, 1152 Dewatering basins, 813 Different speed limits (DSL), 170 Digital surveys, 704 –708 Dilemma zone, 348 –349 Distances from aerial photographs, 714 –717 Distillation of asphalts, 944 –946, 961–963 cutback asphalts, test for, 960 –962 destructive (cracking), 946 emulsions, test for, 962 –963 fractional (steam), 944 –946 processes for petroleum asphalt, 944 –946 Distress (defect) rating (DR), 1142, 1144 –1146 Ditches, see Channels Diverging traffic, 243 Diversion dike, 813 Divisional traffic islands, 286, 289 Dowel bars, 1081 Downgrades, 392, 398 – 400, 414 – 415 freeways, 392, 398 – 400, 414 – 415 level of service and, 392, 397– 400, 414 – 415 two-lane highways, 392, 398 – 400 Drainage, 761–762, 807– 892, 1045 –1046, 1103 area, 816 blankets, 873 – 875 bridges, 809 – 810 channels, 808 – 809, 812, 828 – 843 collectors, 886 – 889 computer models for, 827 culverts, 810 – 811, 844 – 870 curbs, 809, 812 drains, 811, 872 – 874 economic analysis for, 844, 889 erosion control, 811– 813 rigid pavement design for, 1103 flexible pavement design and, 1045 –1046 gutters, 809, 812 highway, 809 – 811, 827– 875 hydraulic design, 827– 870 hydrologic considerations for, 813 – 827, 844 layer, 884 – 886 runoff, 816 – 826 sag vertical curves, criterion for, 761–762 sediment control, 811– 813 slopes, 808, 812 subsurface, 807, 870 – 889 surface, 807– 813, 827– 870 well systems, 874 1213 Drains, 811, 872 – 874 erosion control using, 811 horizontal, 873 intercepting, 811 longitudinal, 872 – 873 subsurface drainage, for, 872 – 873 transverse, 873 – 874 Drivers, 58 – 62, 153, 408, 410 characteristics for traffic, 58 – 62 human response process, 58 – 60 older responses, 61– 62 perception-reaction process, 60 – 61 population effects on LOS, 408, 410 safety-related actions, 153 Dry soil density (gd), 901 Ductility test for asphalt, 964 –966 Durability of asphalt, 950, 960 –961 Duration data for parking studies, 140 –142 Dust percentage, 1016 Dynamic characteristics of vehicles, 74 – 88 Dynamic Shear Rheometer (DSR) test for asphalt, 963 E Earthwork, 723 –730 average end-area method for, 724 –726 cross sections of, 723 –726 grades and, 723 –730 highway location and, 723 –730 mass diagram of, 726 –729 overhaul payments for, 729 –730 terrain and, 723 –730 volumes, computing, 723 –726 Economic evaluations, 657– 669, 695, 844, 889 drainage, 844, 889 benefit-cost ratio (BCR) method for, 666 consumer surplus, 658 – 659 cost elements for, 659 – 663 culverts, 844 drainage design, 844 equivalent uniform annual worth (EUAW) for, 664 – 665 highway location surveys and, 695 internal rate-of-return (ROR) method for, 666 net present worth (NPW) for, 663 – 664 present worth (PW) method for, 663 – 665 Economic growth, Effective resilient modulus, 1043 –1044 Efficiency factors for parking studies, 144 Eight-hour vehicle volume (warrant 1), 336 –337 Eisenhower (National) Interstate Highway System, 16, 44 – 45 Elasticity of travel demand, 633 – 635 Electronic measuring devices (EDM), 701–703 Electronic-principle detectors, 106 –108 Elevation from aerial photographs, 714 –717 Elevations of vertical curves, 764 –767 Embankment formation and control, 927–928 Emergency escape ramps, 791–792 Emergency vehicle preemption, 371–372 Emissions, environmental impact of, 573 Empirical-Bayes method for crash analysis, 165, 173 –175 Employment opportunities, 16 –23 Emulsified asphalt, 947–948, 952, 962 –963, 967–968 demulsibility test for, 967–968 1214 Index Emulsified asphalt (continued) distillation test for, 962 –963 particle-charge test for, 968 process for and use of, 947–948 rate of curing for, 952 sieve test for, 968 End of vertical curve (EVC), 764 –770 Energy grade lines, 858 Energy of subgrade deformation (DE), 1126 Engineering profession, 17–23 employment opportunities in, 18 –23 highway construction, 20 infrastructure specialties, 18 –20 maintenance operations and management, 20 professional challenges in, 20 –23 traffic operations and management, 20 transportation planning, 19 vehicle design and, 17–18 Environmental factors, 154, 176 –177, 682 – 683, 695 – 696, 1041–1044 AASHTO method of pavement design and, 1041–1044 crash conditions and, 176 –177 effective resilient modulus and, 1043 –1044 flexible pavement performance and, 1041–1044 highway location surveys and, 695 – 696 highway safety and, 154 impact on from transportation, 682 – 683 Environmental Impact Statement (EIS), 40, 572 –573, 683 categorical exclusion (CA) for, 572 emissions and, 573 evaluation of alternatives using, 572 –573 finding of no significant impact (FONSI), 572 noise and, 573 Environmental Protection Agency (EPA), 573 Equivalent single-axle loads (ESAL), 1000, 1035 –1040, 1102 –1105 flexible pavement design and, 1035 –1040 growth factors for, 1038 rigid pavement design and, 1102 –1105 superpave system design and, 1000 Equivalent uniform annual worth (EUAW), 664 – 665 Erosion analysis for concrete pavement, 1112 –1121 Erosion control, 811– 813 channel linings, 812 construction and, 812 – 813 curbs, 809, 812 gutters, 809, 812 intercepting drains, 811 slopes, 808, 812 Evaluation of alternatives, 555 –556, 570 –573, 653 – 689, 695 – 696 balance-sheet approaches for, 678 – 679 completed projects and, 679 – 681 cost effectiveness method for, 673 – 676 costs and, 657– 663 criteria for, 655 – 656 decision making and, 657 economic criteria for basis of, 657– 669, 695 environmental impact and, 682 – 683, 695 – 696 environmental impact statements (EIS) for, 572 –573 fact-finding process for, 677– 678 highway location surveys and, 695 – 696 measures of effectiveness, 655 – 657 multiple criteria for, 669 – 683 objectives of, 653 – 654 post facto, 654 procedures for, 657 rating and ranking method for, 669 – 673 social impact and, 682 – 683 stakeholders, identification of for projects, 654 – 655 trade-off approaches for, 678 – 679 transportation planning and, 555 –556, 570 –573, 653 – 689 Excel, fitting speed and density data using, 1183 –1189 Expansion factors, 130 –132 Expansion joints, 1081–1082 Expansion pressure, 934 –935 Expected value (EV) analysis of crashes, 163 –164 Expert systems (ES) for pavement rehabilitation, 1162 Extended segments, two-lane highways, 392 External stations for study area boundaries, 578 Exudation pressure, 934 F Fact-finding process for evaluation, 677– 678 Falling-load deflectometers (FWD) for, 1147–1148 Family-based models for pavement condition, 1152 –1157 Fast-static GPS surveys, 706 Fatality Analysis Reporting System (FARS), 159 Fatigue analysis for concrete pavement, 1111–1121 Faults, see Cracking Federal agencies for transportation, 48 – 49 Federal Aid Highway Act, 562 Federal Highway Administration (FHWA), 41, 569, 584, 662 Federal Transit Association (FTA), 584 Fiducial marks, 709 –710 Field locations of simple horizontal curves, 774 –775 Field procedures for soil compaction, 927–932 Filter requirements for drainage layers, 886 Final highway location surveys, 696 – 697 Finding of no significant impact (FONSI), 572 Fine aggregates, 1078 –1079 Fine-textured soils, 896, 911–912 First costs, 659 Fixed delay, 133 Flash-point test for asphalt, 966 Flexible pavement, 1025 –1074 AASHTO design method for, 1033 –1052 asphalt for, 1027, 1031 base course, 1026, 1041 California method of design for, 1053 –1056 cement for, 1027, 1029 –1031 cracking, 1059, 1066 –1069 effective resilient modulus for, 1043 –1044 equivalent single-axle load (ESAL) for, 1035 –1040 grade equivalent (GE) for, 1053 –1056 Hveem method of design for, 1053 –1056 International Roughness Index (IRI) for, 1058 –1059, 1069 –1070 Mechanistic-Empirical Pavement Design (MEPD) for, 1056 –1070 performance, 1034 –1035 soil characteristics for, 1062 –1063 soil stabilization for, 1027–1032 stress distribution of, 1032 –1033 structural components of, 1025 –1027 Index structural number (SN) for, 1047–1052 subbase course, 1026, 1040 –1041 subgrade, 1026, 1040 surface course, 1026 –1027 traffic index (TI) for, 1053 Float test for asphalt consistency, 958 –959 Floating-car technique for travel time and delay studies, 134 Flow ratio (v/s), 458 – 460, 490 – 495 critical flow (v/c) analysis module and, 490 – 495 saturation flow rate (s) and, 458 – 460 Flushed traffic islands, 256 Fluxing asphalt, 947 Fog seal, 990 Follow-the-leader theory to traffic flow, 228 –230 Ford Model T, 14 Forward-motion compensation (FMC), 718 Four-hour vehicle volume (warrant 2), 337–338 Four-leg intersections, 271–272 Fractional (steam) distillation of petroleum asphalt, 944 –946 Fratar method for growth factors, 610 – 612 Free-flow speed (FFS), 389 –390, 418 – 424, 428 – 430 freeways, 418 – 424 multilane highways, 428 – 430 two-lane highways, 389 –390 Freeways, 373 –377, 406 – 424, 451– 454 adjustment factors (f) for, 452 – 454 criteria of level of service (LOS) for, 411– 412, 451 density for, 418 – 424 downgrades of, 414 – 415 extended segments, 413 – 414 flow rate for passenger cars, 413 free-flow speed (FFS) for, 418 – 424 grades of, 408, 414 – 418 interchange density (spacing), 410 – 411, 420, 454 intersection control for, 373 –377 lane width of, 408 – 409, 419, 453 lanes, number of for, 419, 422 – 424, 454 lateral clearance of, 408 – 409, 419, 454 level of service (LOS), 406 – 424, 451– 454 passenger car equivalents (PCE) and, 408, 410, 413 – 418, 452 – 453 ramps, 373 –377 upgrades of, 414 – 415 Freight, 34 –36, 585 –586, 637– 638 commodity flow data for, 637– 638 estimating demand, 637– 638 modes of transportation for, 34 –36 planning, 585 –586 project-level planning, 585 system-level planning, 585 traffic, 34 –36 travel forecasting, 585 –586, 637– 638 trend analysis of travel, 637 Frequency distribution, 110 –112 Frequency Modulated Continuous Wave (FMCW) system, 106 Friction coefficient, 80 Frontal stationary shock waves, 231–233 Frost action in soils, 936 –937 Full flow energy grade line (EGL), 858 Fundamental diagram of traffic flow, 219 –220 1215 G Gaps, 244 –249 acceptance, 243 –249 critical (tc), 244 –246 exponential distribution for, 247 stochastic approaches to problems of, 247–249 Geographic Information Systems (GIS), 20, 579 –581, 722 –723, 1172 –1174 computer graphics and, 722 –723 database management system (DBMS), 1172 highway construction use of, 20 highway location surveys using, 722 –723 pavement management using, 1172 –1174 travel demand forecasting using, 579 –581 Geometric condition records, 458, 462, 465 Geometric design, 737– 805, 1201–1205 alignment, 754 –790, 795 –796 arterial systems, 739 –740 bicycle facilities, 791–797 climbing lanes, 790 –791 collector street systems, 740 –741 computer programs for, 801 cross-section elements for, 745 –753 design hourly volume (DHV) for, 742 –743 design speed for, 743 –745, 795 design vehicle for, 745 emergency escape ramps, 791–792 heavy vehicle facilities, 790 –791 highway facilities, 737– 805 highway standards for, 742 –754 local systems, 740, 741 maximum highway grades for, 753 –754 metric conversion factors for, 1201–1205 parking facilities, 796 – 801 rural roads, 740 –741 urban roads, 739 –740 Glare vision and recovery, 59 Global positioning systems (GPS), 20, 705 –708, 718 –719 airborne (ABGPS), 718 –719 antennas for, 707 calibration of, 707 computer graphics using, 718 –719 digital surveys and, 705 –708 fast-static surveys, 706 highway construction use of, 20 highway location surveys using, 705 –708 kinematic surveys, 706 least-squares network adjustment for, 708 loop closure for, 708 office procedures for, 708 on-line positioning under service (OPUS) surveys, 706 post-processing for, 708 real-time kinematic (RTK) surveys, 706 receivers for, 706 –707 remote sensing using, 708 repeat baseline analysis for, 708 static surveys, 706 Gradation of aggregates, 969 –974, 1005 –1008 asphalt mixtures, 969 –974 control points, 1006 –1008 maximum density, 1005 –1006 mechanical stabilization, 969 1216 Index Gradation of aggregates (continued) size, 1005 superpave systems, 1005 –1008 Grade equivalent (GE), 1053 –1056 Grade resistance, 74 –75 Grades, 387, 392, 408, 414 – 418, 427– 428, 438 – 439, 445, 447, 469, 723 –730, 753 –754, 754 –760, 996 –1002 adjustment factor (fG), 388, 438-439, 445, 447, 469 alignment of highways and, 754 –760 asphalt binder performance, 996 –1002 composite, 415 – 418 cross sections of, 723 –726 downgrades, 392, 414 – 415 earthwork and, 723 –730 freeways, 408, 414 – 418 geometric design and, 753 –760 highway location and, 723 –730 level terrain, 387 maximum, 753 –754 multilane highways, 427– 428 rolling terrain, 387 shrinkage and, 725 –726 signalized intersections, 469 terrain and, 387, 723 –730, 754 –760 two-lane highways, 287, 392 upgrades, 392, 414 – 415 Gravel (G), 911–912 Gravity models for trip distribution, 604 – 610 Green time, determination of cycle length for, 351–352 Greenberg traffic flow model, 222, 226 –227 Greenshields traffic flow model, 220 –222, 224 –225, 1183 –1189 Ground surveys, 701–704 electronic measuring devices (EDM) for, 701–703 horizontal angle measurement for, 702 –703 level used for, 703 –704 measuring tapes used for, 704 total station for, 701–702 vertical angle measurement for, 703 Ground water, 877– 881 Group index (GI) of soil, 908 Growth factor, 610 – 613, 1038 equivalent single-axle load (ESAL) and, 1038 flexible pavement design and, 1038 trip distribution, models for, 610 – 613 Guard rail cross sections, 749 Gutters, 748 –749, 809, 812 cross sections, 748 –749 erosion control using, 812 surface drainage and, 809, 812 H Hazardous locations and elements, 177–181 critical crash rate (CRF) method for, 177–179 identification of, 177–181 potential for safety improvement (PSI) method for, 179 –181 Headwater elevations of culvert outlets, 863 – 864 Headways, 216 Hearing perception, 60 Heavy vehicle adjustment factor (fHV), 388, 413, 469 Heavy vehicle facilities, 790 –792 climbing lanes, 790 –791 emergency escape ramps, 791–792 Highway Capacity Manual (HCM), 345 –346, 365, 382 –383 Highway Capacity method for signal cycle length, 355 –360 Highway Capacity Software (HCS), 371, 1191–1200 Highway Economic Requirements System (HERS), 662 Highway location, 693 –735 bridges and, 700 –701 computer graphics for, 717–723 economic evaluation for alternatives, 695 environmental evaluation for, 695 – 696 final location survey for, 696 – 697 grades and terrain for, 723 –730 office studies for, 694 preliminary survey for, 695 – 696 plans for, 730 –732 reconnaissance survey for, 694 – 695 recreational routes, 698 scenic routes, 698 surveys for, 693 –735 urban areas of, 698 –700 Highway Performance Monitoring System (HPMS), 130, 156 Highway Safety Improvement Program (HSIP), 155 –190 See also Crashes data collection and maintenance, 155 –159 data storage and retrieval, 156 –160 engineering studies, 181, 183 –189 hazardous locations and elements, identification of, 177–181 improvement implementation and evaluation, 190 project priorities for crash avoidance, 189 Highways, –16, 39 – 47, 151–212, 237–239, 381– 456, 691– 892, 917–922 See also Freeways access control, 193 –195 alignment of, 195 capacity of, 457–547 channels for, 808 – 809, 812, 828 – 843 cross-section elements for, 745 –753 culverts for, 810 – 811, 844 – 870 drainage, 807– 892 Eisenhower (National) Interstate Highway System, 16, 44 – 45 federal support for, 11–12 federal system of, 42 – 45 funds for, 11–12, 42 – 43 geometric design of facilities, 737– 805 historical development of, –16 intercity bus transportation and, 46 level of service (LOS) of, 381– 456 location of, 693 –735 multilane, 424 – 430, 455 – 456, 746 National Highway System (NHS), 43 – 45 national plan for, 10 –11 project development process, 39 – 42 queue lengths at sections of, 237–239 safety design features, 190 –208 safety of, 151–212 shock waves due to speed reductions at sections of, 237–239 soil surveys for construction of, 917–922 surveys, 693 –735, 917–912 truck transportation and, 46 – 47 turnpikes (toll roads), –10 two-lane, 382 – 406, 436 – 451, 745 U.S Bureau of Public Roads, Hinge joints, 1082 Index Histograms, 110 –111 Home-based work (HBO), 595, 602 Horizontal alignment, 770 –790, 795 –796 bicycle paths, 795 –796 compound curves, 778 –781 field locations of, 774 –775 intersection angle () for, 773 long chord for, 773 point of curve (PC) for, 772 point of intersection (PI) for, 772 point of tangent (PT) for, 772 reverse curves, 781–783 simple curve, 771–777 spiral curves, 771, 783, 785 –786 stopping sight distance (SSD) for, 756 –761, 787–790 superelevation (a) of, 783 –787 superelevation runoff for, 783 –785 tangent runouts for, 785 –786 transition curves, 771, 783 –785 Horizontal angle measurement, 702 –703 Horizontal drains, 873 Hot-mix asphalt (HMA), 969 –989, 1003, 1058 –1061, 1064 –1070 aggregate gradation for, 969 –974 asphalt content of, 974 –975 cold-laid, 989 consensus properties of aggregate for, 1003 flexible pavement and, 1058 –1061, 1064 –1070 hot-laid, 969 –989, 1003 job-mix formula for, 974 Marshall methods for, 974 –981 Mechanistic-Empirical Pavement Design (MEPD) and, 1058 –1061, 1064 –1070 property comparison computations for, 976 –981 Hourly expansion factors (HEF), 130 –131 Housing and Urban Development (HUD), U.S Department of, 573 Human response process, 58 – 61 hearing perception, 60 perception-reaction (PIEV) time, 60 – 61 visual perception, 58 – 60 Hveem method of design, see California method of design Hveem stabilometer test, 934 –936 exudation pressure for, 934 expansion pressure for, 934 –935 resistance value (R) for, 935 –936 Hydraulic design, 827– 870 culverts, 844 – 870 open channels, 828 – 843 Hydraulic grade line (HGL), 858 Hydraulic jump in channel flow, 835 Hydrology, 813 – 827, 844 computer models for drainage simulations, 827 culverts, considerations for, 844 drainage, considerations for, 813 – 827 duration of rainfall, 813 frequency of rainfall, 813, 816 intensity of rainfall, 813 – 815 peak-flow, 820, 822, 825 – 827 rainfall and, 813 – 816 runoff, 816 – 826 unit hydrographs for, 826 – 827 Hypothesis testing for crash analysis, 165 1217 I Ice lenses, water from, 881– 883 Impedance of travel, 616 Incremental delay, 494, 496 Inductive loops, 105 Infiltration of water (qi) for drainage, 876 – 877 Information formats for digital surveys, 705 Infrastructure services, employment opportunities in, 19 –20 Inlets, 845 – 852, 866 – 870 bevel-edged, 866 – 867 configuration of, 866 – 870 control coefficients for, 848 – 849 culvert design and, 845 – 852, 866 – 870 flow control, 845 – 852 invert for, 849 – 850 submerged conditions for, 847– 849 tapered, 867– 870 types of, 845 – 846 unsubmerged conditions for, 847– 849 Institute of Transportation Engineers (ITE), 50 –51 Intercepting drains, 811 Interchanges, 265 –266, 327, 330 –332, 410 – 411, 420 – 424, 454 density (spacing), 410 – 411, 420 – 424, 454 intersections compared to, 265 –266, 327 level of service (LOS) effects from spacing between, 410 – 411 types of, 330 –332 Intercity buses, 46 Intermodal connectors, 45 Intermodal Surface Transportation Efficiency Act (ISTEA), 43 Internal rate-of-return (ROR) method of evaluation, 666 International Roughness Index (IRI), 1058 –1059, 1069 –1070 flexible pavement, 1058 –1059, 1069 –1010 JPCP pavement, 1127–1128 Intersection (volume) counts, 132 Intersection angle (), 773 Intersection delay, 500 Intersection design, 200 –202, 265 –325 alignment of, 276 –277 at-grade, 265 –301 channelization of, 285 –294 curves at, 278 –285 four-leg, 271–272 interchanges and, 265 –266 multileg, 271, 273 no-control, 302 –305 pavement widths of turning roadways, 294 –301 profile (vertical alignment) of, 277–278 railroad crossings, 314 –320 safety features for, 200 –202 sight distance at, 301–314 signalized, 312 stop-controlled, 305 –309, 312 T, 267–271 traffic circles, 271–275 yield-controlled, 309 –312 Intersection summary sheets, 124 –125 Intersections, 122 –123, 200 –202, 235 –237, 265 –325, 327–380, 457–547 at-grade intersections, 265 –301 control devices for, 327–380 cordon counts, 122 design of, 200 –202, 265 –325 1218 Index Intersections (continued) freeway ramps, 373 –377 interchanges compared to, 265 –266, 327 isolated, signal timing for, 347–362 lane groups, 344 –345, 458 queue lengths at red phase of signalized, 235 –237 railroad crossings, 314 –320 red phase of, 235 –237 saturation flow rate (s) for, 344 –345, 458 – 460, 468 – 490 shock waves at red phase of signalized, 235 –237 sight distance, 201–202, 301–314 signal timing for, 342 –372 signalized, 235 –237, 312, 457–547 volume traffic studies for, 122 –123 Interstate semitrailer design, 68 –70 Intervals for signal timing, 343, 348 –349 Interviewing method for travel time and delay studies, 139 Inventory method for parking studies, 141 ith-percentile value of speed, 101 ITS (Telematics) advanced technology, 139 J Jam density (kj), 219 Jointed Plain Concrete Pavement (JPCP), 1083, 1121–1128 International Roughness Index (IRI) for, 1127–1128 energy of subgrade deformation (DE) for, 1126 load transfer efficiency (LTE) for, 1126 mean transverse joint faulting, 1125 –1128 Mechanistic-Empirical Pavement Design (MEPD) for, 1121–1128 transverse slab cracking, 1122 –1125 Joints, 1081–1083 butt, 1083 construction, 1083 contraction, 1082 expansion, 1081–1082 hinge, 1082 rigid pavement design using, 1081–1083 K K factors for length of vertical curves, 763 –770 Kinematic characteristics of vehicles, 70 –74 Kinematic GPS surveys, 706 Kinematic viscosity test for asphalt consistency, 956 –957 Kruskal-Wallis H test for crash analysis, 165, 170 –173 L Land use analysis, 584 Lane groups, 344 –345, 458, 466 – 468, 492 – 493 critical, 492 – 493 intersection control and, 344 –345 right-turn-on-red (RTOR), 466 – 468 shared (de facto), 466 signalized intersection LOS, 458, 466 – 468 Lane utilization adjustment factor (fLu), 470, 538 Lane width, 196 –198, 390, 408 – 409, 440, 453, 469, 746 adjustment factor (fLS), 390, 440, 453, 469 cross sections for geometric design, 749 freeways, 408 – 409, 453 level of service (LOS), effects of on, 408 – 409 safety design for, 196 –198 signalized intersections, 469 travel lanes, 746 two-lane highways, 390, 440 Lanes, number of, 419, 422 – 424, 454 Lateral clearance of highways, 408 – 409, 419, 454, 456 League of American Bicyclists, 14 Least-squares network adjustment for GPS surveys, 708 Left-turn adjustment factor (fLT), 470 – 483, 538 Left-turn treatment for signal timing, 360 –361 Level of service (LOS), 34, 36 –37, 381–547, 1191–1200 adjustment factors (f ) for, 434 – 456 average travel speed (ATS), 383, 389 –392, 397– 400, 402 – 406 capacity and, 36 –37, 381–547 criteria for, 383 –387, 411– 412, 436, 451, 455, 461– 462, 535 density (D) and, 418 – 424 determination of using Highway Capacity Software (HCS), 1191–1200 directional segments, 287, 392 – 406, 438 – 439 downgrade effects on, 392, 398 – 400, 414 – 415 driver population effects on, 408, 410 free-flow speed (FFS) and, 418 – 424 freeways, 406 – 412, 418 – 424 interchange spacing, effects on, 410 – 411, 420 intersections, 457–547 lane width effects on, 408 – 409, 419 lateral clearance effects on, 408 – 409, 419, 454, 456 multilane highways, 424 – 430, 455 – 456 operation level analysis for, 382, 460 –516 passenger car equivalents (PCE) and, 408, 410, 413 – 418 percent time-spent-following (PTSF), 383, 387–389, 393 – 402 planning level analysis for, 383, 516 –527 public transportation, 36 –37 transportation value of, 34 two-lane highways, 382 – 406, 436 – 451 two-way highway segments, 387–392, 437– 439 upgrade effects on, 392, 397– 400, 414 – 415 Level terrain, 387, 743 –744 Level used for ground surveys, 703 –704 License-plate observations for travel time and delay studies, 138 Light Detection and Ranging (LiDAR) technology, 719 –721 airborne, 719 computer graphics using, 719 –721 scanner advantages of, 719 –721 software for, 721 terrestrial, 719 Lime, soil stabilization using, 1027, 1031–1032 Linear regression analysis, 223, 228 Linings for channels, 812, 828 – 829, 838 – 843 determination of, 838 – 843 erosion control and, 812, 828 types of, 829 Links, highway systems, 576 –577 Liquid limit (LL), 904 –905 Liquidity index (LI), 905 –906 Load-related cracking, 1066 Load safety factor (LSF), 1110 Load transfer efficiency (LTE), 1126 Local streets, 698, 740 –741 Log arc elasticity, 634 – 635 Long chord, 773 Long Term Pavement Performance (LTPP), 1162 Longitudinal channels, 808 – 809, 812 Longitudinal collectors, 886 – 889 Index backfill material for, 889 locations of pipes, 886 – 888 pipe diameters for, 888 subsurface systems, design of for, 886 – 889 Longitudinal (top-down) cracking, 1066 –1067, 1146 Longitudinal drains, 872 – 873 Loop closure for GPS surveys, 708 Loss coefficients for culvert outlets, 855 – 857 Loss of support (LS), 1096, 1098 Loss-on-heating test for asphalt, 966 M Macroscopic approach to traffic flow, 220 –228 application of models, 222 –223 calibration of models for, 223 –227 Greenberg model for, 222, 226 –227 Greenshields model for, 220 –222, 224 –225 regression analysis for, 223 –227 Manning’s formula for open channel flow, 829 – 834 Manual method for volume counts, 116 –117 Manual on Uniform Traffic Control Devices (MUTCD), 329 –330, 336, 371–372 Markovian model for pavement condition, 1158 –1160 Marshall methods, 974 –981 analysis of results from, 976 asphalt content in mixtures, determination of, 974 –976 property comparison computations for, 976 –981 property curves, 977 stability testing, 975 –976 Mass diagrams, 726 –729 computing ordinates of, 726 –727 interpretation of, 727–729 net accumulation from, 726 –727 Mass transit, see Public transportation Mean free speed (uf), 219 –220 Mean speed, see Average speed Mean transverse joint faulting, 1125 –1128 Measures of effectiveness, 655 – 657 Measuring tapes used for ground surveys, 704 Mechanical soil weathering, 896 Mechanistic-Empirical Pavement Design (MEPD), 1056 –1070, 1121–1128 alligator (bottom-up) cracking, 1059, 1066 criteria for, 1058 –1059 Cumulative Damage Index (DI) for, 1067–1068 energy of subgrade deformation (DE) for, 1126 evaluation of, 1060 –1070 flexible pavement, 1056 –1070 hot-mix asphalt (HMA) and, 1058 –1061, 1064 –1070 input levels for trial pavement structure, 1058 –1061 International Roughness Index (IRI) for, 1058 –1059, 1069 –1070, 1127–1129 Jointed Plain Concrete Pavement (JPCP), 1121–1128 load-related cracking, 1066 load transfer efficiency (LTE) for, 1126 longitudinal (top-down) cracking, 1066 –1067 mean transverse joint faulting, 1125 –1128 non-load-related cracking, 1068 procedure for, 1056 –1058 rigid pavement, 1121–1128 rut depth, 1059, 1061, 1064 –1066 soil characteristics for, 1062 –1063 1219 threshold values for, 1058 –1059, 1122 transverse cracking lengths, 1059 transverse slab cracking, 1122 –1125 weight-in-motion (WIM) data for, 1059 –1060 Median speed, 101 Median type adjustment factor (fM), 456 Medians, 747–748 Medium-curing (MC) asphalts, 947, 955 Merging traffic, 243 Meters, 375 –377 local (isolated), 375, 377 pretimed, 375 –376 ramp closure using, 375 –377 system-wide (coordinated), 375, 377 traffic-response, 376 –377 Metric conversion factors, 1201–1205 Metropolitan planning organization, 563 –564 MicroPAVER software model for pavement condition, 1153 Microscopic approach to traffic flow, 228 –230 Midpoint arc elasticity, 634 – 636 Minimum pedestrian volume (warrant 4), 340 Minimum radius of a curve, 85 – 88, 1203 Modal speed, 101 Mode choice, 584, 613 – 624 direct generation models for, 613 – 614 logit models for, 617– 624 modal split, 584 travel forecasting, 584, 613 – 624 trip end models for, 614 utility functions and, 617– 624 Moisture content (w) of soil, 900, 924 –926 Moisture sensitivity of superpave systems, 1019 Monthly expansion factors (MEF), 131–132 Motor Carrier Management Information System (MCMIS), 160 Mountable curbs, 286 Mountain terrain, 743 –744 Moving-vehicle technique for travel time and delay studies, 135 –138 Multilane highways, 424 – 430, 455 – 456, 746 adjustment factors (f) for, 427– 428, 456 capacity of, 424 – 430 criteria of level of service (LOS) for, 426 – 427, 455 cross section for, 746 density (D) of, 428 – 430 flow rate for, 427– 428 free-flow speed (FFS) of, 428 – 430 grade adjustments for, 427– 428 level of service (LOS) of, 424 – 430 Multileg intersections, 271, 273 Multiple regression analysis, 223 Multiple-regression prediction models for pavement condition, 1157–1158 Multiway stop signs, 334 –335 N National Cooperative Highway Research Program (NCHP), 1162 National Electronic Injury Surveillance System (NEISS), 159 National Highway System (NHS), 43 – 45 National Highway Traffic Safety Administration (NHTSA), 189 National road, 10 –11 Natural Environmental Policy Act (NEPA), 683 1220 Index Near-optimization methods for pavement rehabilitation, 1167–1170 Neighborhood traffic circles, 272 –273 Net inflow (qn) for drainage, 883 – 884 Net present worth (NPW), 663 – 664 No passing zone adjustment factor (fnp), 389, 395, 439, 441– 444 Nodes of highway systems, 576 –577 Noise, environmental impact of, 573 Non-home-based work (NHB), 595, 602 – 603 Non-load-related cracking, 1068 Nondestructive method for soil compaction, 929 O Office studies for highway locations, 694 Off-street parking, 140, 798 – 801 Offset of signal cycle, 343 On-line positioning under service (OPUS) GPS surveys, 706 On-street parking, 140, 797–798 Open channels, see Channels Operation level analysis, 382, 460 –516 capacity and, 490 – 495 critical flow (v/c) analysis module and, 490 – 495 delays and, 494 –500 input parameters for, 462 – 466 level of service (LOS) determined from, 382, 460 –516 performance measures module for, 494 –500 saturation flow rate (s) for, 468 – 490 signalized intersections, 460 –516 Operational delay, 133 Optimization techniques for pavement rehabilitation, 1171–1172 Organic (O) soil, 911–912 Origin-destination (O-D) surveys, 581–583 Outlets, 845, 853 – 864 culvert design and, 845, 853 – 864 energy grade lines for, 858 headwater elevations of, 863 – 864 loss coefficients for, 855 – 857 types of, 853 Overhaul payments for earthmoving, 729 –730 Oversaturated queues, 254 Oversaturation, 461 Oxidation of asphalt, 950 P Pace of speed, 102 Parabolic curves, 756 –757 Parallax of aerial photographs, 714 –717 Paratransit, 36 Parking adjustment factor (fp), 469 Parking facilities, 796 – 801 angle of inclination for, 797–798 garages, 799 – 801 geometric design of, 737– 805 off-street, 798 – 801 on-street, 797–798 surface car parks, 798 –799 Parking studies, 139 –145 accumulation data for, 140 –141 analysis of data for, 144 –145 data collection for, 141–142 duration data for, 140 –142 efficiency factors for, 144 inventory method for, 141 off-street facilities, 140 on-street facilities, 140 parking demand and, 143 parking generators, identification of, 142 –143 space-hours for, 140, 144 terms for, 140 turnover data for, 140 –142 Particle sizes, 896 – 898, 1096 coarse-textured, 896, 911–912 distribution of, 896 – 898 fine-textured, 896, 911–912 organic, 911–912 peat, 911–912 rigid-pavement subbase, distribution of, 1096 soils, 896 – 898 USCS definitions for, 911–914 Particle-charge test for asphalt emulsions, 968 Passenger car equivalents (PCE), 388, 408, 410, 413 – 418, 438, 440, 446, 448 – 450, 452 – 453 freeways, 408, 410, 413 – 418, 452 – 453 RVs (ER), 388, 413 – 414, 438, 440, 446, 448 – 450 tables for, 438, 440, 446, 448 – 450 tables for, 438, 440, 446, 448 – 450, 452 – 453 trucks (ET), 388, 413 – 414, 438, 440, 446, 448 – 450 two-lane highways, 388, 438, 440, 446, 448 – 450 Passengers, 34 –36 Passing lanes, 392, 400 – 405, 450 – 451 adjustment factor (fpl), 450 – 451 two-lane highways, 392, 400 – 405 Passing sight distance, 90 –93 Passing zone combined effect adjustment factor (fd /np), 387, 437 Pavement, 294 –301, 871, 893 –1176 AASHTO design method for, 1033 –1052, 1093 –1108 asphalt, 943 –1023 bituminous materials and, 943 –1023 cement, 946, 1027, 1029 –1031, 1076 –1077 concrete, 1103, 1109 –1121 condition, 1136 –1148, 1151–1160 flexible, 1025 –1074 management of, 1133 –1176 Mechanistic-Empirical Pavement Design (MEPD) for, 1056 –1070, 1121–1128 performance, 1034 –1035, 1094 present serviceability index (PSI), 1035 rehabilitation, 1160 –1172 reliability of, 1045 –1048, 1103 rigid, 1075 –1132 serviceability performance of, 1035 skid resistance, 1148 –1151 soil engineering for, 895 –941 subsurface drainage, performance for, 871 superpave systems, 992 –1019 tests for design of, 932 –936, 953 –968 thickness of, 1093 –1108 widths of turning roadways, 294 –301 Pavement condition, 1136 –1148, 1151–1160 See also Cracking data, importance of, 1136 deterministic models for, 1152 distress, 1141–1146 family-based models for, 1152 –1157 index (PCI), 1146, 1152 –1157 Index Markovian model for, 1158 –1160 MicroPAVER software model for, 1153 multiple-regression prediction models for, 1157–1158 prediction for, 1151–1160 probabilistic models for, 1158 –1160 roughness, 1136 –1140 structural, 1146 –1148 Pavement management, 1133 –1176 approaches to, 1134 condition, 1136 –1148, 1151–1160 data, importance of, 1136 Geographic Information Systems (GIS) used for, 1172 –1174 highway rehabilitation problems, 1133 –1136 levels of, 1134 –1136 programs for, 1162 –1172 rehabilitation, 1160 –1172 roadway conditions, 1136 –1151 Pavement rehabilitation, 1160 –1172 alternatives for, 1161–1162 condition assessment for, 1163 –1165 constraints of, 1171–1172 decision variable identification, 1171 expert systems (ES) computer models for, 1162 near-optimization methods for, 1167–1170 objective function for, 1171 optimization techniques for, 1171–1172 priority assessment models for, 1165 –1170 programs for, 1162 –1172 techniques and strategies for, 1160 –1161 trigger-point ranking, 1165 –1167 Pavement roughness, 1136 –1140, 1058 –1059, 1069 –1070 International Roughness Index (IRI) for, 1058 –1059, 1069 –1070 present service index (PSI) for, 1136 –1137 present service rating (PSR) for, 1136 –1137 profilometers for, 1139 –1140 response-type equipment (meters) for, 1137–1138 Paving mixture, 969 –971, 979 maximum specific gravity of, 979 properties of, 969 –971 Peak-flow discharge (runoff), 820, 822, 825 – 827 Peak-hour factor (PHF), 344, 346 –347, 466 demand flow rate and, 466 design hourly volume (DHV) from, 344, 346 –347 intersection control and, 344, 346 –347 signalized intersection LOS, 466 Peak hour (warrant 3) traffic volume, 338 –339 Peak hour volume (PHV), 116 Peat (Pt), 911–912 Pedestrians, 62, 123, 203 –208, 483 – 488, 699 –700 characteristics of for traffic, 62 crash types and frequency for, 204 –205 occupancy (OCCpedg), 483 – 488 provisions for in urban locations, 699 –700 safety design of facilities for, 203 –208 traffic and, 62, 123 volume counts, 123 Penetration test for asphalt consistency, 958 –959 Percent time-spent-following (PTSF), 383, 387–389, 393 – 402 437– 438, 441– 442, 445 – 448 adjustment factors (f ) for, 387–389, 437– 438, 441– 442, 445 – 448 1221 directional segments, 287, 393 – 402 downgrades, 398 – 400 passing lanes, 400 – 403 two-lane highways, 383, 387–389, 393 – 402 two-way segments, 387–389 upgrades, 397– 400 Perception-reaction (PIEV) time, 60 – 61 Performance measures module, see Delay Periodic volume counts, 123 –124, 128 –132 adjustment of, 130 –132 continuous, 123 control, 123 –124 count stations, determination of number of for, 128 –130 coverage, 124 daily expansion factors (DEF) for, 131 degrees of freedom (v) for, 128 –129 hourly expansion factors (HEF) for, 130 –131 monthly expansion factors (MEF) for, 131–132 traffic studies and, 123 –124, 128 –132 Peripheral vision, 59 Permeability (K), 906 Permitted turn movements, 458 Petroleum asphalt, 944 –946 destructive (cracking) distillation of, 946 fractional (steam) distillation of, 944 –946 Phase, see Signal phase Phase relations of soils, 899 –903 degree of saturation (S), 900 –901 density (D), 901–902 moisture content (w), 900 porosity (n), 899 specific gravity, 901 three-phase principle for, 902 –903 void ratio (e), 899 –900 Photogammetry, see Aerial photographs Physical-distribution management, 19 Pipelines, freight transportation by, 34 –35 Pipes for longitudinal collectors, 886 – 888 Planning-level estimation, 569 –570 Plant mixing, 1029, 1031 Plastic limit (PL), 904 Platoon ratio (Rp), 464 – 466, 536 Pneumatic road tubes, 105 Point of curve (PC), 772 Point of intersection (PI), 772 Point of tangent (PT), 772 Point of vertical intersection (PVI), 764 –770 Points of aerial photographs, 709 –710, 712 –714 Policy committee, 563 Population and economic analysis, 584 Porosity (n) of soil, 899 Position vector for vehicles, 70 Post facto evaluations, 654 Post-processing for GPS surveys, 708 Potential for safety improvement (PSI) method for hazardous locations, 179 –181 Power (P) requirements of vehicles, 76 –78 Preemption and/or priority of vehicles, 371–372 Preliminary highway location surveys, 695 – 696 Prepared road bed, see Subgrade Present service rating (PSR), 1136 –1137 Present serviceability index (PSI), 1035, 1136 –1137 1222 Index Present worth (PW) method of evaluation, 663 – 665 Pressure for soil tests, 934 –935 exudation, 934 expansion, 934 –935 Pretimed (fixed) traffic signals, 349 –360, 362 –365 Prime coats, 991 Principal point of aerial photographs, 709 –710 Priority assessment models for pavement rehabilitation, 1165 –1170 Probabilistic models for pavement condition, 1158 –1160 Profile for highway location, 731 Profile of at-grade intersections, 277–278 Profilometers, 1139 –1140 Progression adjustment factor (PF), 539 Progressive system for arterial signal timing, 370 –371 Proportionality test for crash analysis, 165, 168 –170 Protected-plus permitted options, uniform delay with, 497– 499 Protected turns, 458 Public transportation, 7– 8, 35 –39, 46 See also Urban transportation planning capacity, 36 –37 highways and, 46 historical development of, 7– intercity buses, 46 level of service for, 36 –37 mass transit, 36 paratransit, 36 passenger traffic by, 35 –36 ridesharing, 36 role and future of, 38 –39 urban systems, 7– Pumping of rigid pavement, 1084 –1185 Q QRS model, 616 – 617 Queues (q), 235 –239, 249 –258 arrival distribution of, 253 deterministic analysis of, 235 –250 length, characteristics of, 253 –254 number of channels of, 254 oversaturated, 254 red phase of signalized intersections, at, 235 –237 service distribution for, 254 service method for, 253 shock waves and length of, 235 –239 single-channel, undersaturated, finite, 257–258 single-channel, undersaturated, infinite, 254 –257 speed reductions at highway sections, at, 237–239 stochastic approaches to problems of, 253 –258 traffic intensity of, 255 –256 undersaturated, 254 varying demand and constant service rate causing, 252 –253 varying service rate and constant demand causing, 250 –252 R Radar-based traffic sensors (RTMS), 105 –107 Rail Carload Waybill Sample, 638 Railroad crossings, 314 –320 designs for intersections at, 314 –320 horizontal alignment of, 315 sight distance requirements for, 316 –320 stop line for, 316 –317 traffic-control devices for, 315 vertical alignment of, 315 –320 Railroads, 7, 12 –14, 28 –29, 34 –36 freight traffic by, 34 –36 historical development of, 7, 12 –14 passenger traffic by, 34 –36 selection of transportation by, 28 –29 Rainfall, 813 – 816 Ramps, 82, 373 –377, 791–792 barriers, 374 closure, 374 emergency escape, 791–792 entrance control, 373 –377 exits, 82, 373 manual barricades, 374 meters, 375 –377 stopping distance, 82 Rapid-curing (RC) asphalts, 947, 954 Rate of flow (q), 214, 218 –219 Rate per million of entering vehicles (REMV), 161–163 Rating and ranking method of evaluation, 669 – 673 Rational Factor Ranking Method (FRM), 1164 Rational method for runoff, 820 – 821 Raveling of pavement, 1146 Real-time kinematic (RTK) GPS surveys, 706 Rear stationary and forward recovery shock waves, 231–233 Receivers for GPS, 706 –707 Reconnaissance surveys, 694 – 695 Recreational routes, location of, 698 Refuge traffic islands, 286, 289 –291 Regression analysis for traffic flow, 223 –227 Regression coefficients, equations for, 1181–1182 Regulatory agencies for transportation, 48 Reinforcing steel, 1080 Remote sensing, see Aerial photographs Repeat baseline analysis for GPS surveys, 708 Research and Innovative Technology Administration (RITA), 592 Residual demand delay, 496 Residual soils, 896 Resistance value (R) of soil, 935 –936 Resistivity method for soil exploration, 918 –919 Reverse curves, 781–783 Rheological tests for asphalt, 963 Ridesharing, 36 Right-of-way, 699, 753 Right-turn adjustment factor (fRT), 470 Right-turn-on-red (RTOR), 466 – 468 Rigid pavement, 1075 –1132 aggregates for, 1078 –1080 AASHTO design method for, 1093 –1108 bending stresses in, 1085 –1087 cement (Portland) for, 1076 –1077 coarse aggregates for, 1078 concrete, 1103, 1109 –1121 Continuously Reinforced Concrete (CRCP), 1084 cracking, 1122 –1128 dowel bars for, 1081 equivalent single-axle load (ESAL), 1102 –1105 Index fine aggregates for, 1078 –1079 Jointed Plain Concrete (JPCP), 1083, 1121–1128 joints for, 1081–1083 Mechanistic-Empirical Pavement Design (MEPD) for, 1121–1128 performance, 1094 Portland Cement Association (PCA) design method for, 1109 –1121 pumping, 1084 –1185 reinforcing steel for, 1080 simply reinforced concrete, 1083 steel for, 1080 –1081 stresses in, 1085 –1093 subbase strength, 1094 subgrade strength, 1094 –1102 temperature effects on, 1090 –1093 temperature steel for, 1080 –1081 thickness design of, 1093 –1128 tie bars for, 1081 traffic effects on, 1087–1090, 1102 –1103 water requirements for, 1079 wheel load effects on, 1087–1090 Ring-and-ball softening point test for asphalts, 959 –960 Road detector methods, 105 Road mixing, 1029, 1031 Road tars, 949 Roads, 7–16, 88 –94, 153 –154, 249 –301, 689, 738 –741 See also Freeways; Highways arterial systems of, 739 –740 at-grade intersection design and, 294 –301 collector systems of, 740 –741 early building and planning of, federal support for, 11–12 geometric design of, 738 –741 local systems of, 698, 740 –741 pavement widths of turning, 294 –301 rural, 740 –741 safety-related conditions, 153 –154 sight distance for, 88 –93, 94 traffic operations, characteristics for, 88 –93 turnpikes (toll roads), –10 urban, 739 –740 Roadside barriers, 748 Roadside recovery distance, 198 –200 Roadway conditions, 1136 –1151 distress (defect) rating (DR) for, 1142, 1144 –1146 falling-load deflectometers (FWD) for, 1147–1148 pavement condition index (PCI) for, 1146 pavement distress, 1141–1146 pavement roughness, 1136 –1140 pavement structural condition, 1146 –1148 present service rating (PSR) for, 1136 –1137 present serviceability index (PSI) for, 1136 –1137 skid resistance, 1148 –1151 Roadway network (warrant 8) traffic volume, 341 Rolling resistance (Rr), 75 –76 Rolling terrain, 387, 743 –744 Rotaries, 272 Rotational viscosity test for asphalt consistency, 958 Roundabouts, 274 –275 Running time, 133 1223 Runoff, 816 – 826 antecedent moisture condition (AMC) for, 824 – 825 coefficient (C), 816 – 818 determination of for drainage, 819 – 826 flow travel time, 817– 819 peak-flow, 820, 822, 825 – 826 rational method for, 820 – 821 time of concentration for, 817 U.S Soil Conservation Service (SCS) method for, 821– 826 Rural roads, 740 –741 Rut depth, 1059, 1061, 1064 –1066 Ruts, 1146 S Safety, 151–212 accidents, 152 crashes, 152 –190 driver/operator action, 153 effectiveness of design features for, 190 –208 environmental factors, 154 highway, 151–212 Highway Safety Improvement Program (HSIP), 155 pedestrians, 203 –208 roadway condition, 153 –154 Strategic Highway Safety Plan (SHSP), 154 –190 transportation issues, 152 –154 vehicle condition, 153 Safety design features, 190 –208 access control, 193 –195 alignment of highways, 195 cross sections, 195 –200 effectiveness of, 190 –208 Guidance for Improvement of the AASHTO Strategic Highway Safety Plan, 190 –193 intersections, 200 –202 lane widening, 196 –198 objectives and strategies for, 190 –193 pedestrian facilities, 203 –208 roadside recovery distance and, 198 –200 shoulder widening, 196 –198 sight distance and, 201–202 Sag vertical curves, 756, 760 –770 Salvage value, 660 Sand (S), 911–912 Saturation (S), degree of in soil, 900 –901 Saturation flow rate (s), 344 –345, 458 – 460, 468 – 490, 537 adjustment factors (f) for, 469 – 488, 537 base equation for, 468 bicycle occupancy (OCCbicg) and, 483 – 488 conflict zones and, 483 – 484 field determination of, 488 – 490 flow ratio (v/c) for, 458 – 460 intersection control and, 344 –345 pedestrian occupancy (OCCpedg) and, 483 – 488 signalized intersection LOS, 458 – 460, 468 – 490 Saybolt Furol Viscosity test for asphalt consistency, 953 –956 Scale at points of aerial photographs, 712 –714 Scenic routes, location of, 698 School crossing (warrant 5) traffic volume, 340 Screen line (volume) counts, 122 Seals for asphalt mixtures, 990