00778929

Component

https://doi.org/10.3141/1678-06

http://scholar.google.com...AMDI&publication_year=1999

When vehicles in a queue start crossing a stop line (or any other reference line) at a signalized intersection after the signal turns green, the entering headway (discharge headway) is the time that elapses between consecutive vehicles. This headway is a factor in determining intersection capacity. The current study aims at analyzing the entering headway at selected signalized intersections in Riyadh (the capital of Saudi Arabia). It is unlikely that driver behavior is similar in different countries, and therefore it is unwise to use the values for headway times from other countries to fit traffic conditions in Saudi Arabia. To date, no research of this type has been conducted in Saudi Arabia. This study attempts to investigate the entering headway at intersections in Riyadh and to compare the results with corresponding results from international research. Eight signalized intersections (with two-lane and three-lane approaches) along eight major streets in Riyadh were selected for study. A total of 720 single-lane traffic platoons entering the intersections were observed. It was found that the average entering headways for Vehicles 1 through 15 at two-lane intersections in Riyadh after the light turned green were 3.23, 2.41, 2.29, 2.1, 2.02, 1.84, 1.72, 1.64, 1.53, 1.68, 1.58, 1.31, 1.13, 1.19, and 1.01 s. For the three-lane sites the headways for Vehicles 1 through 13 were as follows: 3.37, 2.23, 2.03, 1.92, 1.81, 1.81, 1.72, 1.69, 1.6, 1.48, 1.37, 1.33, and 1.46 s. The study found that the saturation flow rates were 2,293 and 2,195 vehicles/hour of green per lane for two-lane and three-lane sites, respectively. These intersection approaches appear to have higher saturation flow rates than those in previous studies from other countries.

This paper appears in Transportation Research Record No. 1678, Highway Capacity, Quality of Service, and Traffic Flow and Characteristics.

English

p. 42-47

1999

Transportation Research Record

0309071046

Figures (4) ; References (12) ; Tables (10)

Field studies; Headways; Saturation flow; Signalized intersections; Through traffic; Urban areas

Intersection capacity

Riyadh (Saudi Arabia)

Highways; Operations and Traffic Management; I73: Traffic Control

TRIS, TRB, ATRI

Nov 24 1999 12:00AM

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• APPLICATION OF SUBSET AUTOREGRESSIVE INTEGRATED MOVING AVERAGE MODEL FOR SHORT-TERM FREEWAY TRAFFIC VOLUME FORECASTING
• ARTERIAL PLANNING METHODOLOGY: CONCEPT, IMPLEMENTATION, AND EXPERIENCE
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• CAPACITY STUDY FOR PROTECTED-PERMITTED PHASING FROM SHARED LANES
• CELLULAR AUTOMATA MICROSIMULATION OF BIDIRECTIONAL PEDESTRIAN FLOWS
• COMPARISON OF CAR-FOLLOWING MODELS FOR SIMULATION
• CONGESTED TRAFFIC FLOW: OBSERVATIONS AND THEORY
• ESTIMATING FREE-FLOW SPEEDS FOR RURAL MULTILANE HIGHWAYS
• FREEWAY AND ARTERIAL TRAFFIC FLOW SIMULATION ANALYTICALLY EMBEDDED IN DYNAMIC ASSIGNMENT
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• INVESTIGATION OF SOME CHARACTERISTICS OF CONGESTED FLOW
• INVESTIGATION OF SPEED-FLOW RELATIONSHIP UNDER CONGESTED CONDITIONS ON A FREEWAY
• METHOD FOR ESTIMATING CAPACITY REDUCTION IN HIGH-OCCUPANCY-VEHICLE LANE INGRESS AND EGRESS SECTIONS
• MODELING HETEROGENEOUS TRAFFIC FLOW
• MULTILAYER ARTIFICIAL NEURAL NETWORKS FOR LEVEL-OF-SERVICE ANALYSIS OF SIGNALIZED INTERSECTIONS
• NUMERICAL SIMULATION AND ANALYSIS OF TRAFFIC FLOW
• ON-LINE MONITORING SYSTEM FOR REAL-TIME TRAFFIC MANAGEMENT APPLICATIONS
• PASSING ACTIVITY ON TWO-LANE HIGHWAYS IN SPAIN
• PREPROCESSOR FEATURE EXTRACTOR AND POST PROCESSOR PROBABILISTIC OUTPUT INTERPRETER FOR IMPROVED FREEWAY INCIDENT DETECTION
• PROGRESSION ADJUSTMENT FACTORS FOR UNIFORM DELAY AT SIGNALIZED INTERSECTIONS
• PROPERTIES OF COWAN'S M3 HEADWAY DISTRIBUTION
• QUALITY OF SERVICE FOR INTERRUPTED-FLOW PEDESTRIAN FACILITIES IN "HIGHWAY CAPACITY MANUAL" 2000
• QUALITY OF SERVICE FOR UNINTERRUPTED-FLOW PEDESTRIAN FACILITIES IN "HIGHWAY CAPACITY MANUAL" 2000
• QUEUEING MODEL TO DETERMINE VARIABILITY OF RECURRENT CONGESTION AT FREEWAY LINK OVER A YEAR
• REAL-TIME PREDICTION OF TRAFFIC FLOWS USING DYNAMIC GENERALIZED LINEAR MODELS
• SIMULATION OF LARGE FREEWAY AND ARTERIAL NETWORK WITH CORSIM, INTEGRATION, AND WATSIM
• SOME OBSERVATIONS OF HIGHWAY TRAFFIC IN LONG QUEUES