HCM 6 th Edition: Paul Ryus, P.E. Principal Engineer, Kittelson - PDF document

Instructors HCM 6 th Edition:  Paul Ryus, P.E. • Principal Engineer, Kittelson & Associates, Inc. A Guide for Multimodal • Reston, VA / Svendborg, Denmark Mobility Analysis  Radu Nan, P.E. • Senior Engineer, Kittelson & Associates, Inc. • Boston, MA December 4, 2017 Warwick, Rhode Island 1 2 Workshop Overview Attendee Introductions  Introductions, need for the HCM 6th Edition  Name  Travel time reliability analysis  Organization  Break  Experience with/common uses of the HCM  New freeway analysis methods, freeway case studies  Alternative intersection and interchange analysis  Key questions for today  Lunch  Updated urban street analysis methods  HCM Volume 4  Break  Planning & Preliminary Engineering Applications Guide  Wrap‐up, discussion, additional questions, evaluation 3 4 A Brief History of the HCM The Need for New Research  1950: focus on capacity  Changes in driver behavior  1965: LOS concept, bus transit chapter  Changes in vehicle fleet mix & capabilities  1985: new research, pedestrians, bicycles  Increasing use of certain roadway features in the U.S. • 1994 & 1997 updates • Roundabouts, alternative intersections, managed lanes  2000: new research, multiple parts  Greater methodological sensitivity to factors  2010: new research, multimodal focus, four volumes influencing roadway performance  Broader range of performance measures (e.g., reliability) 5 6 1

HCM 6 th Edition: A Guide for Multimodal Mobility Analysis National Research Since HCM 2010  Published in  NCFRP 41: truck analysis October 2016  NCHRP 03‐96: managed lanes  NCHRP 03‐100: roundabouts in corridors  NCHRP 03‐107: work zone capacity  NCHRP 03‐115: HCM production  NCHRP 07‐22: planning guide to HCM  SHRP 2 L08: travel time reliability  FHWA: ATDM, roundabouts, alternative intersections 8 7 8 Highway Capacity Manual: HCM 6th Edition A Guide for Multimodal Mobility Analysis  Providing mobility for people and goods is  Previous HCM editions have had a year attached transportation’s most essential function. It consists  Looking forward, it is likely that chapters will of four dimensions: continue to be released or updated as new research • Quantity of travel is completed, rather than waiting for a critical mass • Quality of travel to accumulate • Accessibility • Two‐lane highway update • Capacity • Advances in ATDM  Users of the roadway system include motorists, • Connected and autonomous vehicles freight shippers, pedestrians, bicyclists, and  Each chapter has its own version number, allowing passengers in transit vehicles chapters to be updated independently • HCM methods address all these modes 9 10 Growth in HCM Content HCM 6: Not Much Different on the Outside… Printed HCM Online Number of Pages 960 466 Volume 2: Volume 3: Volume 4: Volume 1: 1224 1188 1238 Interrupted Applications Uninterrupted Concepts 512 432 Flow Flow Guide 160 1 9 5 0 1 9 6 5 1 9 8 5 2 0 0 0 2 0 1 0 HCM 6 11 12 2

...But Significant Changes on the Inside The Need for Understanding Hasn’t Changed  New Chapters 11 and 17 on travel time reliability  Using software to implement HCM methods doesn’t diminish the analyst’s responsibility to understand  Basic freeway segment and multilane highway how a method works and to interpret its results methods combined  Furthermore, a subset of HCM users still requires  Many new and updated methods step‐by‐step instructions • Managed lanes, work zones, alternative intersections and • Researchers, software developers, students interchanges, urban street queue spillback, truck effects on freeway operations, and more  Changes to how the HCM presents  Greater focus on providing the information users information were required need to apply HCM methods in software and to interpret analysis results 13 14 Presentation Changes in the HCM 2010 Presentation Changes in the HCM Sixth Edition  Significant changes were made in the HCM 2010  Additional changes have been made for the Sixth Edition • Core information provided in printed chapters • Supplemental, detailed information provided in online • Standardized chapter outlines in Volumes 2 and 3 chapters • Summary tables listing data requirements, • New material on using the HCM in conjunction with potential data sources, suggested default values, and sensitivity of results to inputs alternative tools such as simulation • Research basis for methods provided • Example results in many chapters in Volume 4’s Technical Reference Library • Example problems moved to Volume 4 and expanded to demonstrate new methods 15 16 Standardized Methodological Chapter Outline Example Summary Data Table Suggested Default  Introduction Required Data and Units Potential Data Source(s) Value Geometric Data Determine from functional class, land Highway class (I, II, III) Must be provided  Concepts use, motorist expectation Lane width (ft) Road inventory, aerial photo 12 ft Shoulder width (ft) Road inventory, aerial photo 6 ft  Core Motorized Vehicle Methodology Access-point density (both sides) Class I and II: 8/mi Field data, aerial photo (access points/mi) Class III: 16/mi Terrain type  Extensions to the Methodology* Design plans, analyst judgment Must be provided (level, rolling, specific grade) Level: 20% Percent no-passing zone a (%) Road inventory, aerial photo Rolling: 40%  Mode‐specific Methodologies* More extreme: 80% Base free-flow speed: Direct speed measurements, estimate  Applications Free-flow speed (mi/h) Speed limit + 10 mi/h from design speed or speed limit (see discussion in text) Passing lane length (mi) Field data, road inventory, aerial photo Must be provided Demand Data Hourly demand volume (veh/h) Field data, modeling Must be provided Directional volume split (%) Field data, modeling Must be provided *if provided Analysis period length (min) Set by analyst 15 min (0.25 h) Peak hour factor b (decimal) Field data 0.88 Heavy vehicle percentage (%) Field data 6% c 17 18 3

Example Results Companion Documents  Many methodological chapters now provide example  Highway Safety Manual results  AASHTO Green Book • Demonstrate sensitivity of results to important inputs  Transit Capacity and • Demonstrate potential range of results Quality of Service Manual • Intended to answer many  Manual on Uniform Traffic questions about whether a given result makes sense Control Devices  Not intended to  Traffic Analysis Toolbox substitute for an actual analysis 20 19 20 Why Measure Travel Time Reliability?  Traditional HCM analyses report average conditions during the analysis hour  Actual conditions may vary considerably from day to day—why? TRAVEL TIME RELIABILITY ANALYSIS Crashes/incidents Demand variation/ Severe weather Work zones Special events 21 22 Why Measure Travel Time Reliability? Why Measure Travel Time Reliability?  Traditional HCM performance measures may not fully  As it becomes more impractical to add capacity, capture what travelers experience and remember operations techniques are becoming more widely used • Ramp metering, road patrols, variable speed limits, etc. FHWA FHWA 23 24 4

Why Measure Travel Time Reliability? Travel Time Distribution  Improvements in computing power  A collection of travel time Time Day01 Day02 Day03 Day04 Day05 Day06 0:00 408 434 425 452 437 442 0:05 446 424 449 429 414 436 and automated data collection now observations on a facility over 0:10 480 410 424 419 422 411 0:15 438 418 419 436 416 413 0:20 409 433 476 408 416 419 make it feasible to measure and an extended period of time 0:25 427 455 447 439 451 419 0:30 528 413 424 436 410 439 0:35 433 411 454 411 416 404 0:40 426 429 481 430 411 413 forecast reliability (e.g., a month, a year) 0:45 477 473 440 404 412 413 0:50 442 427 434 401 424 404 0:55 456 422 407 419 424 404 1:00 442 467 437 441 406 447 1:05 432 495 441 416 454 452 1:10 435 424 454 434 422 422 1:15 421 419 471 416 429 432  Measuring reliability addresses the  Once a travel time distribution LOS F problem: Quantifying how has been developed, a variety travelers perceive operations after of useful performance measures a facility breaks down can be developed 25 26 Example Travel Time Distribution: Example Travel Time Distribution: All of February February Weekdays, 6‐9 a.m. Would you say this facility operates reliably? Same facility, shorter time period... Would you say it operates reliably? 27 28 Reliability Reporting Periods Reliability Reporting Periods  The HCM uses the concept of reliability reporting  Different reliability reporting periods have different periods to define the period of time that reliability uses performance measures are being reported for  Examples:  Examples: • All of February or all of the year • All of February  Determining the free‐flow speed (e.g., 5th‐percentile speed)  Freight movement reliability on a rural freeway • All weekday AM peak periods in the year • All weekday AM peak periods in the year • All summer weekends and holidays  Commute trip reliability • All summer weekends and holidays  Reliability on a recreational route during the time of greatest use 29 30 5