Passenger Car Equivalent Estimation Methods of Trucks in Traffic Stream

In Most Of Developing Countries, The Traffic Is Heterogeneous In Nature Consisting Of Wide Variety Of Vehicles Having Different Dynamic And Static Characteristics. Passenger Car Unit (PCU) / Passenger Car Equivalent (PCE) Values Show A Vital Job In Changing Over Heterogeneous Traffic Stream Into Comparable Homogeneous Traffic, Which Comprises Of Traveller Vehicles As It Were. PCE Values Are Vital In Rush Hour Gridlock Stream Investigations. This Paper Reviews The Previous Researches Carried Out About The Estimation Of Passenger Car Equivalents With Different Performance Measures At Mid-Block Sections And Summarizes PCE Variation With Percentage Of Trucks And Flow Rates In The Tabular Form.

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Limitations of Passenger-Car Equivalent Derivation for Traffic Streams with More Than One Truck Type

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/1852-13 ◽

2003 ◽

Vol 1852 (1) ◽

pp. 96-104 ◽

Cited By ~ 25

Author(s):

Sergio Henrique Demarchi ◽

José Reynaldo Setti

Keyword(s):

Quantitative Analysis ◽

Mixed Traffic ◽

Heavy Vehicles ◽

Passenger Car ◽

Flow Rates ◽

Traffic Stream ◽

Passenger Car Equivalent ◽

Traffic Composition ◽

The One ◽

The Impact

Heavy vehicles can have a major impact on traffic streams, particularly on grades. Traditionally, these impacts have been expressed in terms of a passenger-car equivalent (PCE), which is used to convert a mixed traffic stream into a hypothetical passenger-car stream. When the stream contains more than one truck type and truck characteristics differ significantly, it would be desirable to derive PCEs for each truck type. Limitations of current methods of PCE derivation are discussed, and it is demonstrated that PCEs derived individually for each truck type account for only part of the impact caused by trucks on traffic. As a result, distortions are created in the estimation of equivalent flow rates when the traffic composition is different from the one used in the derivation of PCEs. A work-around solution based on the estimation of an aggregate PCE is discussed, and a quantitative analysis of the errors associated with the use of each type of PCE is presented. The results indicate that the errors in the estimation of equivalent flow rates are negligible for densities less than 10 veh/(km-lane) but increase significantly with the increase in density. Equivalent flow rates calculated with aggregate PCEs are not exempt from errors, especially if the traffic mix is different from the one used for the base stream, but these errors were found to be smaller than those caused by the use of PCEs derived individually for each truck type.

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Estimation of passenger car unit for heterogeneous traffic stream of urban arterials: case study of Kolkata

Transportation Letters ◽

10.1080/19427867.2017.1293313 ◽

2017 ◽

pp. 1-13 ◽

Cited By ~ 6

Author(s):

Satyajit Mondal ◽

Sandip Chakraborty ◽

Sudip Kumar Roy ◽

Ankit Gupta

Keyword(s):

Heterogeneous Traffic ◽

Passenger Car ◽

Passenger Car Unit ◽

Traffic Stream ◽

Urban Arterials

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Novel Area Occupancy–Based Method for Passenger Car Unit Estimation on Multilane Urban Roads Under Heterogeneous Traffic Scenario

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/2615-10 ◽

2017 ◽

Vol 2615 (1) ◽

pp. 82-94 ◽

Cited By ~ 4

Author(s):

Raunak Mishra ◽

Pallav Kumar ◽

Shriniwas S. Arkatkar ◽

Ashoke Kumar Sarkar ◽

Gaurang J. Joshi

Keyword(s):

Traffic Flow ◽

Performance Measure ◽

Area Ratio ◽

Heterogeneous Traffic ◽

Passenger Car ◽

Traffic Conditions ◽

Passenger Car Unit ◽

Wide Range ◽

Traffic Volumes ◽

Measure Of Performance

This research was aimed at developing an area occupancy–based method for estimating passenger car unit (PCU) values for vehicle categories under heterogeneous traffic conditions on multilane urban roads for a wide range of traffic flow levels. First, PCU values of vehicle categories were determined according to the Transport and Road Research Laboratory definition and replaced the commonly considered measure of performance speed with area occupancy using simulation. The PCU values obtained were found to be significantly different for different volume-to-capacity ratios; this result shows that the PCU value is dynamic in nature. While the dynamic nature of PCU values is well appreciated, practitioners may prefer a single set of optimized PCU values (unique for each vehicle category). Hence, a new method with a matrix solution was proposed to estimate the optimized or unique set of PCU values with area occupancy as the performance measure. To check the credibility of the proposed method, the estimated PCU values were compared from existing guidelines regulated by the Indian Roads Congress (IRC) and values estimated with the widely accepted dynamic PCU concept of speed–area ratio. Results show that the PCU values suggested by IRC and the dynamic PCU concept using the speed–area ratio underestimate and overestimate the flows, respectively, at different traffic volumes. However, the values obtained with the area-occupancy concept were found to be consistent with the traffic flow in a cars-only traffic situation at different flow conditions. The derived set of optimized PCU values proposed can be useful for traffic engineers, researchers, and practitioners for capacity and level-of-service analysis under heterogeneous traffic conditions.

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Measuring the Passenger Car Equivalent of Small Cars and SUVs on Rainy and Sunny Days

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198118758638 ◽

2018 ◽

Vol 2672 (31) ◽

pp. 110-119 ◽

Cited By ~ 4

Author(s):

Majid Zahiri ◽

Xiqun (Michael) Chen

Keyword(s):

Field Investigation ◽

Urban Traffic ◽

Heterogeneous Traffic ◽

Motor Vehicles ◽

Mixed Traffic ◽

Passenger Cars ◽

Passenger Car ◽

Passenger Car Equivalent ◽

The Government ◽

Rainy Days

Traffic volume is a fundamental measurement in traffic analyses. In mixed traffic, vehicles vary in size, length, headway, spacing, and acceleration/deceleration. Therefore, if we can categorize the vehicles in mixed traffic in greater detail, the estimated passenger car equivalent (PCE) number will be more accurate. Practical and appropriate methods that convert different vehicles into the equivalent number of passenger cars need to be employed to determine PCE factors for heterogeneous traffic. Following economic growth and increased use of motor vehicles in developing countries, the purchase of sports utility vehicles (SUVs) continues to grow, though the government encourages people to buy small cars because of the limited road capacity, as well as air pollution problems. In this research, we categorize passenger cars into three subsets: small cars (hatchback cars without a trunk), SUVs, and standard cars (taxis and typical family cars). A field investigation shows that the penetration rates of these passenger cars are 12%, 23%, and 55%, respectively (10% are other vehicles) in Hangzhou, China. We also measure the PCE value for small cars and SUVs using the mean time headway method. Because different countries have different weather conditions, we continue to measure the PCE values for sunny days and moderate rainy days. The results show that PCE values for small cars and SUVs are 0.87 and 1.26 on sunny days, and 0.87 and 1.31 on rainy days, respectively. By using the PCE with high precision, urban managers can accomplish the analysis of urban traffic with greater accuracy.

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Determining passenger car equivalent (PCEs) for pretimed signalized intersections with severe motorcycle composition using Bayesian linear regression

PLoS ONE ◽

10.1371/journal.pone.0256620 ◽

2021 ◽

Vol 16 (9) ◽

pp. e0256620

Author(s):

Sugiarto Sugiarto ◽

Fadhlullah Apriandy ◽

Yusria Darma ◽

Sofyan M. Saleh ◽

Muhammad Rusdi ◽

...

Keyword(s):

Linear Regression ◽

Heterogeneous Traffic ◽

Signalized Intersection ◽

Common Source ◽

Passenger Car ◽

Traffic Characteristics ◽

Bayesian Linear Regression ◽

Passenger Car Equivalent ◽

Saturation Flow ◽

Traffic Operation

Pretimed signalized intersection is known as a common source of congestion, especially in urban heterogeneous traffic. Furthermore, the accuracy of saturation flow rate is found to cause efficient and vital capacity estimation, in order to ensure optimal design and operation of the signal timings. Presently, the traffic also consists of diverse vehicle presence, each with its own static and dynamic characteristics. The passenger car equivalent (PCE) in an essential unit is also used to measure heterogenous traffic into the PCU (Passenger Car Unit). Based on the collection of observed data at three targets in Banda Aceh City, this study aims to redetermine the PCEs by using Bayesian linear regression, through the Random-walk Metropolis-Hastings and Gibbs sampling. The result showed that the obtained PCE values were 0.24, 1.0, and 0.80 for motorcycle (MC), passenger car (PC), and motorized rickshaw (MR), respectively. It also showed that a significant deviation was found between new and IHCM PCEs, as the source of error was partially due to the vehicle compositions. The present traffic characteristics were also substantially different from the prevailing conditions of IHCM 1997. Therefore, the proposed PCEs enhanced the accuracy of base saturation flow prediction, provided support for traffic operation design, alleviated congestion, and reduced delay within the city, which in turn improved the estimation of signalized intersection capacity.

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