traffic microsimulation & 3-d visualization presenters: fadi emil nassar, p.e. veronica a. boza,...
TRANSCRIPT
TRAFFIC MICROSIMULATION & 3-D VISUALIZATION
Presenters: Fadi Emil Nassar, P.E.Veronica A. Boza, E.I.
FDOT – MAY 4, 2007
MACRO / MICRO TRAFFIC MODELS
MACRO MODEL: TRAFFIC FORECASTMICRO MODEL: OPERATIONAL ANALYSIS NO LONGER SEPARATE FILEDS:
– DISTRIBUTION IMPACTED BY OPERATIONS– CAPACITY CONSTRAINT AT INTERSECTIONS– TRANSIT/MODAL SPLIT IMPACTED BY CONGESTION
GAP CLOSING BTW MACRO & MICRO ANALYSESCONVERGENCE OF SOFTWARE INTEGRATED MODELS:
– CUBE / DYNAMISM– VISUM / VISSIM
TRAFFIC MICROSIMULATION MODELS
ANALYZE THE PERFORMANCE OF TRANSPORTATION SYSTEMS BY SIMULATING THE MOVEMENTS OF INDIVIDUAL VEHICLES ON A SPLIT-SECOND BASIS
ACCOUNT FOR ROADWAY, DRIVER AND VEHICLE CHARACTERISTICS
OPERATIONAL RESULTS (SPEED, QUEUES, DELAYS, ETC) ARE BASED ON TRAFFIC INTERACTION INSTEAD OF EQUATIONS
3D-VISUALIZATION
COMPLEX ROADWAY SYSTEMSBRIDGESOVERPASSES INTERCHANGESAIRPORT TERMINAL RAMPSVIEW FROM CAR
SR 112 - MIAMI
WHEN TO USE MICROSIMULATION
LIMITATION OF HCM / HCSSYSTEM ANALYSIS (COORDINATION)CONGESTION / SPILLBACK / BOTTLENECKQUEUING / STORAGECLOSELY SPACED RAMPSBUS / MULTIMODAL / ITS / RAMP METERINGSIGNAL PRE-EMPTIONCOMPLEX OR UNIQUE GEOMETRY
SIMULATION PROCESS
STUDY OBJECTIVESMODEL SELECTIONDATA COLLECTIONBASE MODEL DEVELOPMENT CALIBRATION / VALIDATIONALTERNATIVE ANALYSISMOE SUMMARY / PREFERRED ALTERNATIVEPRESENTATION OF RESULTS
STUDY OBJECTIVES
GOALS OF MODELING PROCESSESTABLISH NEED FOR MICROSIMULATIONPROJECT SCOPING
– LIMITS OF ANALYSIS / INFLUENCE AREA– BOUNDARY CONDITIONS – TIME PERIOD– PEAK HOUR FACTOR
LEVEL OF DETAIL / EFFORT / BUDGETUNDERSTAND MODEL STRUCTURE
– DELAY, QUEUE, DRIVER BEHAVIOR
MOE DIFFERENT FROM HCM EQUATIONS
MODEL SELECTION
BASIC MODELSCORSIMSYNCHRO/SIMTRAFFIC
ADVANCED MODELSVISSIM / AISUM / CUBE DYNAMISMPARAMICS & OTHERSCOMBINATION OF MODELS
CORSIM
LINK-NODE NETWORK (DEVELOPED BY FHWA)ADVANTAGES:
– WIDELY USED & ACCEPTED– EXTENSIVE VALIDATION IN USA– FREEWAY/RAMP OPERATION– BUS ROUTES – ITS ANALYSIS – RAMP METERING– TIME PERIOD ANALYSIS– LINK AGGREGATION– SHORT/LONG INCIDENT SIMULATION– HEADWAY DISTRIBUTION TYPES
CORSIM (CONTINUE)
DISADVANTAGES:– 2-D ONLY (NO ELEVATIONS)– SIMPLIFIED SIGNAL OPERATION– PROBLEMS WITH SHORT LINKS– RESULTS GROUPED PER LINKS– NO SIGNAL OPTIMIZATION– NO INTERSECTION LOS– IMPROVED BUT LIMITED GRAPHICAL INTERFACE
CORSIM-CYPRESS
Alternative 1
Alternative 2
Partial Cloverleaf Interchange:
•Limited Spacing of Interchange
•Stacks queue in one or more quadrants
•Requires Extensive ROW
•Complex Design
Diamond Interchange•Sufficient Spacing•Simple Design•Narrow ROW•Stopped Condition
CORSIM – INTERCHANGE ALTERNATIVES
SYNCHRO/SIMTRAFFIC
LINK-NODE NETWORK (TRAFFICWARE)ADVANTAGES:
– WIDELY USED– EASY DATA ENTRY / BEST GRAPHIC INTERFACE – EXPORT TO CORSIM / T7F / HCS / VISSIM – DATABASE INTERFACE (VOLUME/SIGNAL/LAYOUT)– INTEGRATED SIGNAL OPTIMIZATION– ROUNDABOUT MODELING (NOT YET VALIDATED)– INTERSECTION LOS (HCM / ICU)– DIAMOND INTERCHANGE / RING & BARRIER– QUEUE LENGTH (PERCENTILE)– EASY TO CREATE SUB NETWORKS
SYNCHRO/SIMTRAFFIC (CONTINUE)
DISADVANTAGES:– NO TRANSIT MODELING– LIMITED FREEWAY CAPABILITY– SIMTRAFFIC RESULTS DIFFER FROM SYNCHRO & NOT
WIDELY ACCEPTED – LINK-BASED MOEs– LIMITED FLEXIBILITY OUTSIDE BASIC INTERSECTIONS
(TOLL PLAZA, AIRPORT, SIGNAL PREEMPTION, ITS, ETC)
SYNCHRO - UNIVERSITY OF MIAMI
SAMPLE SYNCHRO/SIMTRAFFIC NETWORK
Becker Road
I-95
CORSIM Network
PORT ST. LUCIE
ADVANCED - VISSIMLINK-CONNECTORDEVELOPED BY PTV IN GERMANYADVANTAGES:
– INCREASING ACCEPTABILITY IN US– EXTENSIVE TRANSIT MODELING CAPABILITY
• LIGHT RAIL• BUS TRANSIT WITH BUS STATIONS• ROUTE ASSIGNMENT BASED ON SCHEDULE
– EXPLICIT PEDESTRIAN & CYCLIST MODELING– 3D GRAPHIC OUTPUT / IMPACT OF GRADES– ADVANCED SIGNAL CONTROL LOGIC
• IMPORTANT FOR DEMAND RESPONSIVE OPERATION• IMPORTANT FOR SIGNAL PREEMPTION
VISSIM (CONTINUE)
ADVANTAGES:– ADVANCED ORIGIN-DESTINATION– ROUTING FOR ALL VEHICLE TYPES– DYNAMIC ASSIGNMENT (VISUM)– ROUNDABOUT SIMULATION– UNLIMITED VEHICLE TYPE
• IMPORTANT FOR TOLL PLAZA• AIRPORT CURB SIDE OPERATION
– FLEXIBLE DATA COLLECTION– INTERFACE WITH 3-D MODELER– DYNAMIC VISUALIZATION OF RESULTS
VISSIM (CONTINUE)
DISADVANTAGES:– NOT AS WIDELY USED IN FLORIDA– EXPENSIVE (WITH TRANSIT OPTION)– CODING OF DESIRED OUTPUT PARAMETERS– FLEXIBILITY REQUIRES GREATER KNOWLEDGE AND
CODING EFFORTS – NO STANDARD SUMMARIES WHICH COMPLICATE
REVIEW PROCESS– NO SIGNAL OPTIMIZATION (INTERFACES WITH
SYNCHRO)
MIAMI - PROPOSED ROUNDABOUT
DATA COLLECTION
GEOMETRY & LAYOUTTRAFFIC CONTROL: SIGNAL & SIGNVOLUMES (RECONCILE COUNTS)DATA FOR CALIBRATION
– TRAVEL TIME– AVG & FREEFLOW SPEED– QUEUE LENGTH– OBSERVATIONS / WARNING SIGNS
BASE MODEL DEVELOPMENT
DEVELOP LINK-NODE DIAGRAMNODE NUMBERING / PROPER CODINGBASE MAPPINGDATA COLLECTION / FIELD REVIEWCHECK INPUT DATABALANCE VOLUMESDEVELOP O-D MATRIX (RAMPS)SIGNAL TIMINGQA/QC – CHECK SIMULATION RUNSVERIFIABLE / REPRODUCIBLE / ACCURATE
VOLUME CALIBRATIONCONGESTED CONDITIONS
(EX: SR112)
DATA COLLECTION INITIAL CALIBRATION RESULTSADDITIONAL INVESTIGATIONDEMAND PEAK HOUR VOLUMESTRAVEL TIMES
DATA COLLECTION
Legend:Signalized IntersectionUnsignalized IntersectionRoadway Split AreasTurn Lane Storage Length
Posted Speed Limit
1
100'
Ockeechobee Rd/N. River Drive
From SR 112Ramp
1?
130'
110'110'
ToFlyover
250'
Flyover
75'
325'
ToAirport
FlyoverFrom NB
Le Jeune Road
23
4
5
7
EBL used to re-direct traff ic to NBLe Jeune fromOckeechobee &Le Jeune Int.
1
Bridge overMiami River From SR 112
Ramp
NW 36 Street
5
WB - NW 36 Street
2
6
3
FromSR 112 500'
4
7
EB -NW 36 Street
To EB SR 112Ramp
ToNW 42 Ave
6
100'
Driveway
65'
WB SR 112 Ramp toOckeechobee Road:
Fourth lane starts west ofNW 32nd Ave and ramp
separat ion starts atNW 35th Ct
30MPH
30MPH
1
11
6
5
4
2
1
9
108
3
Intersection Count Location
Machine Count Location
Ramp Count Location
1
1
5
4
6
9
1
3
7
8
2
7
6
5
4
3
2
1
8
7
12
INITIAL CALIBRATION RESULTS
VISSIM not replicating observed queues with measured volumes:– Traffic backups on ramps and intersections
– Tri-Rail and Freight Train Impact on traffic
Significant difference is travel times
Need for additional investigation
ADDITIONAL INVESTIGATION Intersections Peak Hour Factors (PHF) greater than 0.95
suggests constrained conditions.
Intersection AM Peak Hour PM Peak Hour
Le Jeune Rd/SE 8 St 0.98 0.97
Le Jeune Rd/Okeechobee Rd: 0.98 0.99
Le Jeune Rd/NW 36 St 0.97 1.00
Le Jeune Rd/NW 31 St 0.95 0.95
NW 36 Street/Lee Dr 0.98 0.98
NW 36 St/S. River Dr 0.97 0.95
NW 36 St/N. River Dr 0.97 0.97
ADDITIONAL INVESTIGATION
Location TO/FROMQuality Counts
FDOT Stations
AM PM AM PM
WB SR-112 Off Ramps
To Okeechobee RdTo NW 36 StreetTo AirportTo SB Le Jeune Rd
5.2%8.0%6.7%6.7%
3.5%6.3%7.5%8.9%
4.2%8.7%n/a6.3%
11.1%5.8%n/a7.2%
EB SR-112 On Ramps
From Okeechobee RdFrom NW 36 StreetFrom AirportFrom NB Le Jeune Rd
12.3%9.7%4.2%5.7%
4.7%8.1%9.5%7.6%
10.9%n/an/a4.2%
5.3%n/an/a8.4%
Peak to daily factors (K-factor) less than 8.5% on freeways and 9.0% for arterials suggest constrained conditions.
Ramps:
ADDITIONAL INVESTIGATION
Location AM PM
Le Jeune Rd, South of NE 8 St 5.8% 7.1%
Le Jeune Rd, South of NW 31 St 5.8% 4.4%
N. River Dr, West of Flyover merge
8.6% 6.6%
N. River Dr, North of NW 36 St 6.6% 5.8%
N. River Dr, South of NW 36 St 6.9% 7.5%
S. River Dr, East of Le Jeune Rd 6.5% 6.2%
S. River Dr, West of NW 36 St 6.5% 9.4%
NW 36 St, West of N. River Dr 6.5% 6.4%
NW 36 St, East of N. River Dr 5.1% 6.1%
Arterials
VOLUME ADJUSTMENT
Adjustment to achieve demand volumes based on FDOT Quality/Level of Service Handbook:– Ramps:
•Minimum K100 is 8.5%; and
•Average Peak to daily ratio percent difference is 28% and 26% for the AM and PM Peak Hours respectively.
– Arterial Road:•Minimum K100 is 9.0%; and
•Average Peak to daily ratio percent difference is 27% for both the AM and PM Peak Hours.
VOLUME BALANCING (SEASONAL FACTOR / TRUCKS / ETC)
CALIBRATION / VALIDATIONDRIVER BEHAVIOR
– STARTUP DELAY & REACTION TIME– MINIMUM HEADWAY/GAP ACCEPTANCE– LANE CHANGE PARAMETERS– CAR FOLLOWING SENSITIVITY
VEHICLE CHARACTERISTIC– TRAFFIC COMPOSITION– MAXIMUM ACCELERATION / DECELERATION
ROADWAY CHARACTERISTICS– FREE FLOW SPEED– CHANNELIZATION– PARKING ACTIVITY
TRAVEL TIMES AM Peak Hour
SegmentCollected Travel
Time Range (Sec)
VISSIM Travel Time
(Sec)
SR-112 Off ramp
232 - 291 235
EB NW 36 St 178 - 295 195
WB NW 36 St 273 242 PM Peak Hour
SegmentCollected Travel
Time Range (Sec)
VISSIM Travel Time (Sec)
SR-112 Off ramp
430 - 580 394
EB NW 36 St 180 - 655 204
WB NW 36 St 229 - 380 368
NB Le Jeune Rd
248 - 303 266
SB Le Jeune Rd 281 - 445 285
ALTERNATIVE ANALYSIS / MOE
SIMULATION GREAT FOR ALT ANALYSIS SIMPLIFIED REALITY / LIMITATIONS ESTABLISH MOE & MATRIX EVALUATION
– SPEED– DENSITY– TRAVEL TIME– QUEUE– DELAY
PERFORM MULTIPLE RUNS (SEED #) SENSITIVITY ANALYSIS PRESENTATION OF RESULTS
– GRAPHIC SIMULATION– OPERATIONAL RESULTS