00802597

Component

https://doi.org/10.3141/1710-21

http://scholar.google.com...hias&publication_year=2000

Control delay for left-turning vehicles at unsignalized intersections was observed in the field and compared with average control delay calculated from the methodologies presented in the 1997 update of the "Highway Capacity Manual" (HCM). Unsignalized intersections with two-way left-turn lanes on the major street were observed in the peak and off-peak hours, and control delays were recorded for the one-state and two-state left-turn processes. Next, the methodologies presented in the HCM were used to calculate the control delay for both processes and compared with the observed data. These comparisons were used as the basis for validation of the HCM methodologies regarding left-turn control delay at unsignalized intersections. From the comparisons, the calculated delay closely corresponds with the observed data, with a total approach volume at the intersection of approximately 2,500 vehicles per hour or less. Once the total approach volume increases above this level, the calculated values rapidly increase and the actual observed control delays gradually increase at a much lower rate. As a result, the observed and calculated delays are different when the intersection handles more than 2,500 approach vehicles in an hour. Statistical analyses were performed on the data to determine if the average observed control delay was related to the calculated control delay. Statistically, the observed control delay and the calculated control delay at the 95% confidence level show that the two data sets yield similar results for off-peak conditions. However, during the peak hour, when the total approach volumes are higher, the 95% confidence interval yields different results. Hence, the HCM procedures produce, on average, greater control delay estimates than the field observations when the total approach volumes are high.

This paper appears in Transportation Research Record No. 1710, Traffic Flow Theory and Highway Capacity 2000.

English

p. 181-188

2000

Transportation Research Record

0309066891

Figures (4) ; References (3) ; Tables (3)

Left turns; Off peak periods; Peak periods; Statistical analysis; Traffic data; Traffic delays; Traffic volume; Two way left turn lanes; Unsignalized intersections; Validation

Highway Capacity Manual

Data and Information Technology; Highways; Operations and Traffic Management; I71: Traffic Theory

TRIS, TRB

Nov 29 2000 12:00AM

• ANALYTICAL EXPRESSIONS OF INCIDENT-INDUCED FLOW DYNAMICS PERTURBATIONS: USING MACROSCOPIC THEORY AND EXTENSION OF LIGHTHILL-WHITHAM THEORY
• ANALYZING ARTERIAL STREETS IN NEAR-CAPACITY OR OVERFLOW CONDITIONS
• CAR-FOLLOWING AND COLLISION CONSTRAINT MODELS FOR UNINTERRUPTED TRAFFIC: REEXAMINATION USING HIGH-PRECISION GLOBAL POSITIONING SYSTEM DATA
• CHARACTERIZING AND MODELING OBSERVED LANE-CHANGING BEHAVIOR: LANE-VEHICLE-BASED MICROSCOPIC SIMULATION ON URBAN STREET NETWORK
• COMPARISON OF QUEUE-LENGTH MODELS AT SIGNALIZED INTERSECTIONS
• DELAY VARIABILITY AT SIGNALIZED INTERSECTIONS
• DETERMINATION OF CAPACITY AT ALL-WAY STOP-CONTROLLED INTERSECTIONS
• DEVELOPMENT OF DRIVER POPULATION FACTORS FOR CAPACITY ANALYSIS OF SIGNALIZED INTERSECTIONS
• EFFECTS OF RELAXATION AND ANTICIPATION ON RIEMANN SOLUTIONS OF PAYNE-WHITHAM MODEL
• ESTIMATION AND APPLICATION OF DYNAMIC SPEED-DENSITY RELATIONS BY USING TRANSFER FUNCTION MODELS
• EVALUATION OF CORSIM CAR-FOLLOWING MODEL BY USING GLOBAL POSITIONING SYSTEM FIELD DATA
• EXPERIMENTAL VERIFICATION OF TIME-DEPENDENT ACCUMULATION PREDICTIONS IN CONGESTED TRAFFIC
• FREEWAY FACILITY METHODOLOGY IN "HIGHWAY CAPACITY MANUAL" 2000
• GAS-KINETIC MODELING AND SIMULATION OF PEDESTRIAN FLOWS
• MODELING FOUR-DIRECTIONAL PEDESTRIAN FLOWS
• NEW INSIGHTS INTO FREEWAY CAPACITY AT WORK ZONES: EMPIRICAL CASE STUDY
• NEW MODEL FOR EVALUATION OF TRAFFIC OPERATIONS AT ELECTRONIC TOLL COLLECTION PLAZAS
• OBSERVATION-BASED LANE-VEHICLE ASSIGNMENT HIERARCHY: MICROSCOPIC SIMULATION ON URBAN STREET NETWORK
• PREDICTIVE TIME-BASED FEEDBACK CONTROL APPROACH FOR MANAGING FREEWAY INCIDENTS
• QUASI-VARIATIONAL INEQUALITY APPROACH TO MULTI-USER-CLASS DYNAMIC TRAFFIC ASSIGNMENT
• SIMULATION LABORATORY FOR EVALUATING DYNAMIC TRAFFIC MANAGEMENT SYSTEMS
• THEORY OF BREAKDOWN PHENOMENON AT HIGHWAY BOTTLENECKS
• USER ASSESSMENT OF INTERSECTION CHAPTER PROCEDURES IN "HIGHWAY CAPACITY MANUAL" 1997 UPDATE
• VALIDATION OF HIGH-FIDELITY TRAFFIC SIMULATION MODELS
• VALIDATION RESULTS FOR FOUR MODELS OF OVERSATURATED FREEWAY FACILITIES
• VARIATIONS IN CAPACITY AT SIGNALIZED INTERSECTIONS WITH DIFFERENT AREA TYPES
• WEAVING AREA ANALYSIS IN YEAR 2000 "HIGHWAY CAPACITY MANUAL"