01663988

Component

https://doi.org/10.1177/0361198118798723

https://doi.org/10.1177/0361198118798723

Traffic congestion costs drivers an average of $1,200 a year in wasted fuel and time, with most travelers becoming less tolerant of unexpected delays. Substantial efforts have been made to account for the impact of non-recurring sources of congestion on travel time reliability. The 6th edition of the Highway Capacity Manual (HCM) provides a structured guidance on a step-by-step analysis to estimate reliability performance measures on freeway facilities. However, practical implementation of these methods poses its own challenges. Performing these analyses requires assimilation of data scattered in different platforms, and this assimilation is complicated further by the fact that data and data platforms differ from state to state. This paper focuses on practical calibration and validation methods of the core and reliability analyses described in the HCM. The main objective is to provide HCM users with guidance on collecting data for freeway reliability analysis as well as validating the reliability performance measures predictions of the HCM methodology. A real-world case study on three routes on Interstate 40 in the Raleigh-Durham area in North Carolina is used to describe the steps required for conducting this analysis. The travel time index (TTI) distribution, reported by the HCM models, was found to match those from probe-based travel time data closely up to the 80th percentile values. However, because of a mismatch between the actual and HCM estimated incident allocation patterns both spatially and temporally, and the fact that traffic demands in the HCM methods are by default insensitive to the occurrence of major incidents, the HCM approach tended to generate larger travel time values in the upper regions of the travel time distribution.

18-06088

English

pp 93-104

2018

Transportation Research Record: Journal of the Transportation Research Board

Print

Figures (6) ; Maps; References (36) ; Tables (3)

Calibration; Case studies; Freeways; Methodology; Reliability; Spatial analysis; Time domain analysis; Traffic congestion; Traffic data; Traffic delays; Traffic incidents; Travel time; Validation

Highway Capacity Manual; Interstate 40

Durham (North Carolina); Raleigh (North Carolina)

Highways; Operations and Traffic Management; Planning and Forecasting

TRIS, TRB, ATRI

Jan 8 2018 11:34AM

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• Defining Freeway Design Capacity Based on Stochastic Observations
• Estimating Passenger Car Equivalents on Level Freeway Segments Experiencing High Truck Percentages and Differential Average Speeds
• Evaluation of the Roundabout Capacity Model in HCM6 Edition and HCM 2010 on a Multilane Roundabout
• Impact Assessment of Short-Term Work Zones on Intersection Capacity in New York City
• Investigating Entry Capacity Models of Roundabouts under Heterogeneous Traffic Conditions
• Modeling Free-flow Speeds on Undivided Roads in Mixed Traffic with Weak Lane Discipline
• Modeling the Impacts of Traffic Flow Arrival Profiles on Ramp Metering Queues
• Multimodal Level of Service Methodologies: Evaluation of the Multimodal Performance of Arterial Corridors
• Saturation Flow Model for Signalized Intersection under Mixed Traffic Condition
• Total Capacity of Roundabouts Analyzed by a Conflict Technique
• Traffic Operations on Rural Two-Lane Highways: A Review on Performance Measures and Indicators