11th TRB National Transportation Planning Applications Conference CORRADINO May 9, Validation of Speeds and Volumes in a Large Regional Model Southeast Regional Planning Model – 6 Florida Department of Transportation District IV

2 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 Consultant Team SERPM 6 Corradino AECOM Consult With thanks to … FDOT Districts 4, 6 & Turnpike MPO staffs of Palm Beach, Broward 7 & Miami-Dade Counties SFRTA

3 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 SERPM 6 Palm Beach, Broward and Miami- Dade Counties 4,134 TAZs (ZONESA) 3 Time periods (AM 6:30-9:30, PM 3:30 – 6:30, Off-peak) 10 Transit modes 22 – 28 hours run time on 3.4 GHZ computer

4 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 SERPM 6 - Transit Nets #PT Mode (applicable county)TRNBUILD Mode (applicable county) 1Walk Access 2Drive Access 3Sidewalk/Transfer connector 4Bus (Palm Beach & Broward)Bus (Palm Beach) 5Bus (Miami-Dade)Bus (Dade) 6Express Bus (all)Express Bus (Broward) 7Metro-Rail 8Tri-Rail 9Metromover 10New Mode (all)New Mode (Broward) 11Project Mode (all) 12Tri-Rail Shuttle (all) 13Limited Stop Bus (all)Limited Stop Bus (Miami-Dade) 14n/aBus (Broward) 15n/aExpress Bus (Miami-Dade) 16n/aExpress Bus (Palm Beach) 17n/aNew Mode (Miami-Dade) 18n/aLimited Stop Bus (Broward) 19n/aLimited Stop Bus (Palm Beach) 20n/aNew Mode (Palm Beach)

5 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 SERPM 6 – Model Flow 1.Setup controls and file names 2.External – EE by period 3.Trip Gen – LSGEN by auto ownership and TOD 4.Highway – Including speed and capacity calculators 5.Distribution – Including equilibration of peak period highway speeds 6.Transit Nets – PT  Trnbuild and connectors, paths, skims and fares 7.Mode Choice 8.Transit Assignment by access path and TOD 9.Highway Trip Tables – Combines trip tables for assignment 10.Highway Assignment – by TOD (use most computer time) 11.Highway Evaluation – HEVAL and RMSE by TOD and county

6 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 THE ISSUE FTA/FHWA emphasis on correct speeds and travel times in models, especially for New Starts So, we must: Match traffic counts and transit ridership in the base year. Match traffic counts and transit ridership in the base year. Match observed highway travel times Match observed highway travel times Match observed transit travel times Match observed transit travel times

7 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 Old Practice Assign uncongested speeds and capacities to links from a lookup table indexed by area type (AT), facility type (FT) and number of lanes. Default lookup table developed by examining practice throughout the state. Adjust the lookup table to obtain a better match of final assigned 24-hour volumes. Most adjustments made to speeds. Care taken to ensure “logical” relationships, e.g., freeways faster than arterials, rural faster than residential. Transit speeds derived from highway using “INET” functions based on mode, AT and FT.

8 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 Well, What’s Wrong With That? Lookup table probably better than adjusting individual links to get better loads (not dead yet – what speed does a new link get?). While lookup tables are systematic, their contents can become arbitrary and skewed. Seldom checked to verify they have any relationship to reality.

9 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 New Approach Base Capacities on Florida Quality/Level of Service Manual, derived from HCM. Capacities and speeds determined from roadway characteristics, not a subjective determination of AT, FT. Speeds begin with POSTED SPEED, modified by studies of driver behavior. If signal controlled, add estimated delays at intersections, but not microsimulation (somewhat of a slippery slope). Some concessions were made to better match counts.

10 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 Initial Speed Estimation Estimates uninterrupted flow initial speed from an equation. Begin with NCHRP 387 Begin with NCHRP 387 Modify to make more consistent (remove discontinuity at 50 mph). Modify to make more consistent (remove discontinuity at 50 mph). Adds delays from traffic control devices Later, speeds are changed in the user equilibrium assignment and equilibration of travel times.

11 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 Speed Relationships FWY= *Postspd *Postspd^2 Surface= *Postspd *Postspd^2

12 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 CAPACITIES New with SERPM-6. Replaces the lookup tables. Allows an OVERIDE coded on the link. Based on the FDOT Quality/Level of Service Manual. Script calculates LOS “C” and “E”. Calculated as PCE’s.

13 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 Capacity Calculation Variables/Attributes

14 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 Time of Day FSUTMS uses auto speeds from 24-hour assignment as for HBW mode choice HBO & NHB use free-flow speeds HBO & NHB use free-flow speeds SERPM6 uses time of day Peak period trips use AM congested speeds Peak period trips use AM congested speeds Off-peak period trips use free-flow speeds Off-peak period trips use free-flow speeds Standard FSUTMS design expected for most models Standard FSUTMS Models Purpose & Period Auto Impedances HBW all Congested HBO all Free-flow NHB all Free-flow Time-of-day Models Purpose & Period Auto Impedances HBW peak HBO peak NHB peak AM congested HBW off-peak HBO off-peak NHB off-peak Free-flow

15 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 Equilibration Peak speeds and time modified from user equilibrium assignment. Run twice to conserve model running time. Speeds found to be stable. Produces distribution and mode choice travel times for highway and transit that are close to the times after the final assignment. Times are stable for UB calculations.

16 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 SERPM 6 – Mode Choice Applied for Peak and Off-peak

17 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 SERPM 6 – Highway Assignment By Time-of-Day AM Peak AM Peak Off-Peak Off-Peak PM Peak PM Peak Composite 24 Hours (add preceding) Composite 24 Hours (add preceding)

18 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 Volume-Delay Curves Southeast Regional Planning Model VI

19 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 SERPM 6 – Highway Evaluation SUMMARIES BY: SERPM 6 Region by Time-of-Day SERPM 6 Region by Time-of-Day Each County for 24 hours Each County for 24 hours Trucks alone – each County for 24 hours Trucks alone – each County for 24 hours

20 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 SERPM 6 - Validation Standard FSUTMS Plus Speed Validation Speed compromises made in favor of Volume/Count Good Volume/Count ratios Very good RMSE Good transit assignment results

21 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 Highway Sections of Observed Speed Study (from several sources)

22 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, Highway Speeds

23 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 SERPM 6 – Speed Validation Average Weighted Speed (mph) ModelObserved Facility TypeAMPM Off Peak All Periods AMPM Off Peak All Periods Freeway Surface Streets HOV Lanes Toll Facility All Facilities:

24 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 AM Period Speed Validation

25 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 PM Period Speed Validation

26 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 Off-Peak Speed Validation

27 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 SERPM 6 – Systemwide Comparison

28 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 SERPM 6 – RMSE Validation

29 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 Highway Screenline Accuracy

30 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 Screenline Locations

31 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 Volume/Count Ratios of Screenlines

32 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 Conclusions Assigning speeds to network links based on posted speeds and traffic control produces good results in terms of speeds and travel times. The Florida Quality/Level of Service Manual is useful for estimating model capacities. Speed and capacity calculators appear to work at least as well as lookup tables and are less arbitrary. It is possible to validate speeds and volumes in a time-of-day model.

33 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 Recommendations for Future Study Need consistent travel time data. Need more travel time data. Consider estimating delays at intersections dynamically using software intersection or junction modeling. Better way of estimating the impacts of freeway merge/diverge/weaves on model travel times.

34 11th TRB National Transportation Planning Applications Conference CORRADINO May 9, 2007 Questions ? Please use the Microphone.