Knoxville Regional Travel Demand Model Upgrade Program. May 6, 2004

Transkript

1 Knoxville Regional Travel Demand Model Upgrade Program May 6, 2004

2 Agenda TAZ Database External Trips Roadway Network Network Editing Tools Speed Capacity Estimation Signal Impedance Model Interface Trip Generation Trip Distribution Vehicle Occupancy & Time of Day Traffic Assignment Resolution of Calibration Issues & Final Validation Statistics Post-Processing

3 Expanded Study Area

4 Traffic Analysis Zones Total of 747 TAZ 717 Internal zones 30 External zones 45 Data Attributes Demographic data from Census 2000 Employment by 10 major industry classes University student enrollment & residence K-12 th grade enrollments

5 External Trips 30 External Stations 34,000 daily trips Five Interstates Average 25.2% through 21 Other Stations Average 1.2% through

6 External Trips (Cont d) , , ,842 3,827 3,827 2, ,

7 Roadway Network Multi-scenario Network Master input network Over 140 attributes fields containing reference data Eighteen scenario-specific modeling fields to simplify the development and testing of different network assumptions Network editing tools Tools for developing and managing network scenarios Tools to simplify the coding of traffic signal attributes Output network Over 170 attribute fields with detailed outputs from the travel model and post-processors

8 Roadway Network Master Network Wealth of reference data All MINUTP model attributes Geographic & operational characteristics from TRIMS Observed speeds from congestion management studies Scenario-specific assumptions Number of lanes by direction Lane and shoulder widths Presence of median Posted speed Access control Area type Traffic signalization, priority, and synchronization

9 Roadway Network Output Networks Scenario geometric and operational assumptions Estimated free-flow speeds and capacities Loaded traffic volumes by direction and time-of-day Segment VMT & VHT by mode Average congested speeds by timeof-day Level of Service Peak 15 minute speeds and flow densities VOC, CO, NOx Emissions

10 Network Editing Tools Scenario Tools List Scenarios Add Scenario Delete Scenario Copy Projects

11 Network Editing Tools Signal Tools Update Signal Fields Add Signals Delete Signals Import Signals from GIS Layer

12 Speed & Capacity Estimation Free-flow speeds developed from extensive speed survey data Capacity estimation based on the Highway Capacity Manual 2000 methodologies Facility type = f (number of lanes, access control, presence of median, directionality, area type) Free-flow speed = f (facility type, posted speed) Capacity = f (facility type, number of signals, approach priority, signal synchronization, lane width, shoulder width, % heavy vehicle, directional distribution)

13 Speed & Capacity Estimation 1.00 Capacity Reduction Factor for Lateral Clearance adjustment factor free-flow speed 6 ft 3 ft 0 ft lateral clearance

14 Signal Impedance HCM 2000 procedure Delay/veh = uniform delay * PF + incremental delay + initial queue delay where, PF = progression factor = f (arrival type, g/c) 2 0.5C( 1 g C) uniform delay = 1 [ min( 1, v c) g C] Varying g/c s based on approach priority (higher, equal to, or lower than cross street 0.60, 0.50, 0.40 g/c) Varying arrival types based on signal synchronization (isolated signal vs. series of signals) Default cycle lengths = 90 sec.

15 Model Interface

16 Trip Generation Six internal auto trip purposes: HBW, HBS, HBU, HBO, NHBW & NHBO Trip production and attraction rates for auto mode developed from 2000 Knoxville Household Travel Behavior Study Trip production: Predictive variables determined by non-parametric correlation analysis Cross-classification table dimension developed by ANOVA Trip attraction: Multivariate regression techniques Special university trip generation components for UT based on 1999 IU travel behavior study (both dorm based and commuter) Special tourist trip generation for southern Sevier County

17 Trip Generation (Cont d) Trip Production Model Trip Purpose 1 st Predictor 2 nd Predictor Trip Rate HBW Workers/H.H. Vehicles/H.H HBS Students/H.H. None 0.61 HBU University Student/TAZ None 0.15 HBO Household Size Vehicles/H.H NHBW Workers/H.H. Household Income 0.80 NHBO Household Size Vehicles/H.H Total 7.42

18 Trip Generation (Cont d) Trip Attraction Model Trip Purpose Independent Variable Parameter HBW Total Employment Trip Purpose Independent Variable Households Parameter HBS K-12 Enrollment Retail Employment NHBO HBU University Enrollment Office Employment Population Gov t. Employment Retail Employment Labor Employment HBO Office Employment Industrial Employment Trucks Gov t. Employment Retail Employment Population Office Employment Retail Employment Auto Total Employment^ NHBW Office Employment Ex/In Households (Other) Gov t. Employment NHBW Total Employment Other Employment (Work)

19 Trip Distribution Six internal trip purposes (HBW, HBS, HBU, HBO, NHBW & NHBO) & E-I trips Friction Factors from 2000 Knoxville Household Travel Behavior Study (network skims of geocoded trip ends) Attractions balanced to productions Doubly-constrained gravity model Socioeconomic (or K) factors to help balance county-tocounty flows and other important interactions

20 Trip Distribution (Cont d) Friction Factor Calibration for Home-Based Work Trip Length Frequency Distribution Time BTLFD TLFD#5 TLFD#10 TLFD#15

21 Trip Distribution (Cont d) Feedback Loop for the Knoxville Model

22 Time of Day AM peak (7:00~9:00), PM peak (3:00~6:00), and Off-peak Factors for internal auto purposes from the 2000 Knoxville Household Travel Behavior Study Factors for other purposes from various sources TOD factors to split the 24-hr trip table into tables by TOD TOD factors by trip purpose Directional factors to convert trip tables in a productionattraction format to origin-destination tables Directional factors by trip purpose and by TOD

23 Time of Day (Cont d) Trips by Purpose by Hour HBW HBK12 HBU HBO NHBW NHBO EI EE TRK

24 Time of Day (Cont d) Time of Day & Directional Factors AM PM OFF DAILY AM PM OFF DAILY HBW 27.5% 29.1% 43.4% 100.0% NHO 8.7% 24.8% 66.6% 100.0% p-a 26.6% 2.9% 23.1% 52.6% p-a 4.3% 12.4% 33.3% 50.0% a-p 0.9% 26.2% 20.3% 47.4% a-p 4.3% 12.4% 33.3% 50.0% HBS 49.2% 30.0% 20.8% 100.0% EI 7.8% 20.8% 71.4% 100.0% p-a 49.2% 0.6% 4.7% 54.5% p-a 1.8% 12.9% 35.0% 49.8% a-p 0.0% 29.4% 16.1% 45.5% a-p 6.0% 7.8% 36.4% 50.2% HBU 29.8% 19.6% 50.5% 100.0% EE 7.8% 20.8% 71.4% 100.0% p-a 29.8% 2.5% 22.5% 54.9% p-a 3.9% 10.4% 35.7% 50.0% a-p 0.0% 17.1% 28.0% 45.1% a-p 3.9% 10.4% 35.7% 50.0% HBO 14.7% 25.4% 60.0% 100.0% TRK 11.0% 15.0% 74.0% 100.0% p-a 11.8% 9.6% 26.7% 48.2% p-a 5.5% 7.5% 37.0% 50.0% a-p 2.8% 15.8% 33.2% 51.8% a-p 5.5% 7.5% 37.0% 50.0% NHW 16.0% 25.7% 58.3% 100.0% p-a 2.2% 21.5% 31.3% 55.0% ALL 15.9% 25.3% 58.8% 100.0% a-p 13.9% 4.2% 26.9% 45.0%

25 Mode Share Private Auto Mode Share by Purpose (from HH Survey) Mode Share HBW 98% HBS 73% HBU 78% HBO 98% NHBW 98% NHBO 96%

26 Vehicle Occupancy Vehicle Occupancy by Purpose by Time of Day (from HH Survey) AM PM OFF HBW HBS HBU HBO NHBW NHBO

27 Traffic Assignment Time-of-day assignments (i.e., separate AM-peak, PM-peak & Offpeak assignments) Directional flows by time-of-day User equilibrium assignment by mode with trucks preloaded Calibrated volume-delay functions by functional class and signalization Roadway Class Volume Delay Parameters Alpha Beta Rural Interstate Urban Interstate Other Freeways Signalized Unsignalized Alpha Beta Alpha Beta Rural Principal Arterials Urban Minor Arterials Rural Collectors Other

28 Traffic Assignment (Cont d) Final Validated Assignment

29 Resolution of Calibration Issues Issue: Global Under-Loading Solution: ODOT Factors for Trip Under-reporting - from GPS validation of household travel surveys Trip Purpose Under-reporting Factor Home-Based Work 1.22 Home-Based School 1.41 Home-Based University 1.41 Home-Based Other 1.60 Non-Home Based Work 2.32 Non-Home Based Other 2.18

30 Resolution of Calibration Issues Issue: Southern Sevier County Under-Loading Solution: Special Tourist Trip Generation Data on Tourism from National Park Service & Sevier County Economic Development Council ITE Trip Generation Rates for Occupied Hotel Rooms (8.17/day)

31 Resolution of Calibration Issues Issue: I-40 East Over-Loading Solution: Special Morristown External Attractions Data on inter-county flows from CTPP journey to work data Convert externalinternal trip productions to HBW & HBO attractions

32 Resolution of Calibration Issues Issue: Over-Loading High Class Facilities & Under-Loading Low Class Facilities Solution: Calibrated Volume-Delay Function Parameters Knoxville Regional-Volume Delay Curves Speed Decay V/C 8.0/4.5.40/2.7.83/ / / / / / /7.0 14/4.5 12/6.0

33 Resolution of Calibration Issues Issue: Unbalanced Interactions between Area Types and with External Stations Solution: Socioeconomic (K) Factors Average K Factors

34 Final Validation Results All the MDOT error criteria were met Final Global Average Loading Error: -1.68% Final Global VMT Error: -0.15% Final Root Mean Square Error: 31.96%

35 Final Validation Results Model Performance by Volume Group Volume Range Average Counts Average Loading % RMSE % Error % Threshold VMT % Error 1,001 ~ 2,000 1,476 2, ± ,001 ~ 3,000 2,461 3, ± ,001 ~ 4,000 3,448 3, ± ,001 ~ 5,000 4,483 4, ± ,001 ~ 6,000 5,461 5, ± ,001 ~ 8,000 7,033 7, ± ,001 ~ 10,000 8,910 8, ± ,001 ~ 15,000 12,107 11, ± ,001 ~ 20,000 17,349 15, ± ,001 ~ 25,000 22,361 20, ± ,001 ~ 30,000 27,633 26, ± ,001 ~ 40,000 33,890 33, ± ,001 ~ 50,000 43,730 42, ± ,001 ~ 60,000 57,730 59, ± > 60,000 66,828 70, ± ALL 11,531 11,

36 Final Validation Results Model Performance by Functional Class Functional Classification Average Counts Average Loading % RMSE % Error VMT % Error Rural Interstate 44,246 45, Rural Prin. Arterial 16,395 16, Rural Minor Arterial 9,352 9, Rural Major Collector 4,322 4, Rural Minor Collector 3,545 3, Rural Local Roads 3,075 2, Urban Interstate 39,960 41, Urban Prin. Arterial 23,240 21, Urban Minor Arterial 10,336 9, Urban Collectors 7,123 6, Urban Local Roads 4,348 3, All 11,531 11,

37 Final Validation Results Model Performance by Major Corridor Corridor Average Counts Average Loading % RMSE % Error VMT % Error I-40 48,552 51, I-75 44,374 44, I ,023 31, I ,645 25, I-81 36,804 38, I ,365 18, Chapman Hwy 24,608 24, US129 37,999 33, SR66/US321 34,303 34, Pellissippi Pkwy 16,588 18, SR62 22,616 19,

38 Final Validation Results Model Performance by Screenline, Area Type, & County Screenline Area Type County Category Avg Counts Avg Loading % RMSE % Error VMT % Error Knox County Line 15,530 15, Blount County Line 10,350 10, Knox & Blount C.L. 12,013 11, Knox-Blount Border 18,643 19, Major Employment District 13,469 12, Urban Areas 11,648 10, Suburban Areas 14,019 13, Rural Areas 10,442 11, Knox County 11,679 11, Blount County 9,597 8,

39 Post-Processing POST_ALT Average Congested Speeds Level of Service Traffic Statistics Report AQ_PLuS Emissions by Roadway Segment County Total Emissions Report CAL_REP Calibration Statistics

40 POST_ALT: Average Speeds Average congested speeds by time of day were validated against observed speed data from Congestion Management Studies 32.77% RMSE for AM Speeds 33.69% RMSE for PM Speeds 27.98% RMSE for Off Peak Speeds

41 POST_ALT: Level of Service Level of Service based on Highway Capacity Manual 2000 criteria by facility type: Flow-Density for freeways, expressways, & multilane divided highways Percent time spent following & speed decay for rural two-lane highways Speed decay for urban streets

42 POST_ALT: Traffic Statistics Traffic statistics by functional class, area type, county, and corridor - including user-defined corridors: CLASS MILES VMT AUTO_VM TRUCK_VMVHT AUTO_VH TRUCK_VHAVGSPEED DELAYPTC VC User Corridor # User Corridor # User Corridor # User Corridor # User Corridor # User Corridor # User Corridor # User Corridor # User Corridor # User Corridor #

43 AQ_PLuS: Link Emissions Link-Specific Emissions Volatile Organic Compounds Carbon Monoxide Oxides of Nitrogen in grams/day

44 AQ_PLuS: County Conformity Emissions summaries by county to facilitate conformity determinations Air Quality Conformity Analysis Report for Knoxville Region from MOBILE6 and the Knoxville Regional Travel Demand Model Mon Mar 29 02:08: Year: 2000 Scenario: TestAQ VMT in Knox County VOC CO NOx Scenario: tons/day tons/day tons/day

45 Knoxville Transit Analysis Tool Regression Model Predicts riders per service hour for a route Using Population density Mean household income Average household workers per household vehicles Retail employment density of the area within a quarter mile of the route

46 THANK YOU!