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

2003 ◽  
Vol 1852 (1) ◽  
pp. 96-104 ◽  
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.

scholarly journals The effect of the traffic composition on the urban traffic capacity. Passenger car equivalent coefficients

2021 ◽  
Author(s):  
Dmitri Nemchinov ◽  
Dmitri Martiakhin ◽  
Pavel Pospelov ◽  
Tatiana Komarova ◽  
Alexandr Mikhailov
Keyword(s):  
Traffic Flow ◽  
Russian Federation ◽  
Urban Traffic ◽  
Heavy Vehicles ◽  
Passenger Cars ◽  
Passenger Car ◽  
Traffic Capacity ◽  
Equivalent Number ◽  
Passenger Car Equivalent ◽  
Traffic Composition

Predicting the traffic capacity and its elements requires bringing the traffic flow represented by various vehicles to uniformity expressed in the equivalent number of passenger cars, through the use of the passenger car equivalent coefficients (PCE). The currently used in Russian Federation passenger car equivalent coefficients are taken on the basis of studies of the capacity of the Russian Federation, carried out in the 70s - 80s of the last century on rural roads, where most of the vehicles were heavy vehicles. Currently, the traffic flow is mostly represented by passenger cars. The riding qualities of cars, especially trucks, have changed significantly. This situation is especially common to Moscow. In this regard, the question of clarifying the traffic flow composition and revising the passenger car equivalent coefficients becomes relevant. The article presents the methodology and results of studies carried out on the route sections between road crossings to determine the passenger car equivalent coefficients and the traffic composition in Moscow.

scholarly journals Passenger Car Equivalent Estimation Methods of Trucks in Traffic Stream

2020 ◽  
Vol 8 (5) ◽  
pp. 710-716
Keyword(s):  
Performance Measures ◽  
Heterogeneous Traffic ◽  
Estimation Methods ◽  
Tabular Form ◽  
Static Characteristics ◽  
Passenger Car ◽  
Flow Rates ◽  
Passenger Car Unit ◽  
Traffic Stream ◽  
Passenger Car Equivalent

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.

Developing Mixed Traffic Equivalency Factors to Estimate Saturation Flow at Urban Signalized Intersections

2021 ◽  
pp. 036119812110186
Author(s):  
Pinakin N. Patel ◽  
Ashish Dhamaniya
Keyword(s):  
Signalized Intersections ◽  
Mixed Traffic ◽  
Heavy Vehicles ◽  
Commercial Vehicles ◽  
Passenger Car ◽  
Flow Rates ◽  
Geometric Conditions ◽  
Metropolitan Cities ◽  
Equivalency Factors ◽  
Saturation Flow

This study proposes a time occupancy approach to estimate passenger car units (PCUs) at urban signalized intersections with different interaction levels between vehicles under saturated green time conditions. The study shows a variation in PCUs with varied traffic and geometric conditions. Traffic data have been collected through videography techniques at signalized intersections in three metropolitan cities in India. Traffic flow discharge and clearance time of different vehicular categories have been extracted from the video during the saturated green time. The observed ranges of dynamic PCU values for two-wheelers, three-wheelers, big cars, light commercial vehicles, and heavy vehicles are 0.12 to 0.32, 0.45 to 0.80, 1.40 to 1.80, 1.60 to 2.20, and 3.50 to 6.50, respectively. Regression-based PCU models have been developed for each vehicle category to address the variation of individual vehicle PCUs with traffic compositions and flow rates. The model analysis shows that traffic compositions and flow rates are significantly affecting the PCU values. The PCU is a complex parameter requiring several field attributes. Therefore, to overcome the complexity of estimating PCUs, a concept of flow equivalency factor (FEF) has been proposed based on the estimated PCUs. The FEF can directly convert the mixed motorized vehicular flow into an equivalent standard passenger car flow without actually making use of different vehicles’ PCU factors. All the developed models have been validated for field conditions and results are found promising with field data. The developed approach can be used effectively for developing countries with a mixed traffic stream.

scholarly journals EVALUATING THE EFFECT OF HEAVY VEHICLES ON TRAFFIC PARAMETERS BY USING HEAVY VEHICLE FACTOR

2018 ◽  
Vol 6 (4) ◽  
pp. 95-104
Author(s):  
Parthkumar Patel ◽  
H.R. Varia
Keyword(s):  
Travel Time ◽  
Traffic Flow ◽  
Road Traffic ◽  
Freight Transport ◽  
Heavy Vehicle ◽  
Mixed Traffic ◽  
Heavy Vehicles ◽  
Highway Traffic ◽  
Ideal Situation ◽  
The Impact

Safe, convenient and timely transportation of goods and passengers is necessary for development of nation. After independence road traffic is increased manifold in India. Modal share of freight transport is shifted from Railway to roadways in India. Road infrastructures continuously increased from past few decades but there is still need for new roads to be build and more than three forth of the roads having mixed traffic plying on it. The impact of freight vehicles on highway traffic is enormous as they are moving with slow speeds. Nature of traffic flow is dependent on various traffic parameters such as speed, density, volume and travel time etc. As per ideal situation these traffic parameters should remain intact, but it is greatly affected by presence of heavy vehicle in mixed traffic due to Svehicles plying on two lane roads. Heavy vehicles affect the traffic flow because of their length and size and acceleration/deceleration characteristics.  This study is aimed to analyse the impact of heavy vehicles on traffic parameters.

Determining Passenger Car Equivalent for Motorcycle at Mid-Block of Sesetan Road

2015 ◽  
Vol 776 ◽  
pp. 95-100
Author(s):  
I. Gusti Raka Purbanto
Keyword(s):  
Motor Vehicles ◽  
Heavy Vehicles ◽  
Highway Capacity ◽  
Passenger Car ◽  
Highway Capacity Manual ◽  
The Road ◽  
Traffic Conditions ◽  
Mode Share ◽  
Passenger Car Equivalent ◽  
On The Road

Motorcycle dominates traffic in Bali, particularly in urban roads, which occupy more than 85% of mode share. The three types of vehicles, i.e. motorcycles, heavy and light vehicles share the roadways together. Under mixed traffic conditions, motorcycle may be travelling in between and alongside two consecutive motor vehicles. Considering such a situation, passenger car equivalent values should be examined thoroughly. This study aims to determine passenger car equivalent (PCEs) of motorcycle at mid-block of Sesetan Road. Three approaches are used to examine the PCEs values. This study found that the PCE of motorcycles are in a range between 0.2 and 0.4. This values are about the same to the existing PCE of the Indonesian Highway Capacity Manual (1997). This study also pointed out that motorcyclists and car drivers may behave differently to the existence of motorcycles. Car drivers are more aware than motorcyclists on the existence of motorcycle on the road. Further, more samples are required to obtain comprehensive results. In addition, the presence of heavy vehicles need to be considered for future study.

scholarly journals The impact of heavy vehicle’s composition to traffic performance of Jakarta Intra Urban Toll Road (JIUT) in macroscopic level

2019 ◽  
Vol 276 ◽  
pp. 03018
Author(s):  
Nahry Yusuf ◽  
Ismi Dilianda Wulandari
Keyword(s):  
Traffic Flow ◽  
Exponential Model ◽  
Flow Speed ◽  
Heavy Vehicles ◽  
Flow Models ◽  
Toll Road ◽  
Traffic Performance ◽  
Traffic Flow Models ◽  
The One ◽  
The Impact

Freight vehicle access restriction policy in 2011 has had an impact on the performance of Jakarta Intra Urban Toll way (JIUT) system. The statutory segment (Cawang-Tomang) of this toll road system seems to have better performance, but not for the advisory segment (Cawang -Ancol). Basically, heavy vehicles (HV) shift their routes to the advisory segment to avoid the statutory segment at which they are prohibited to access from 05.00 a.m. to 10.00 p.m.. This study aims to investigate the impact of the HV composition on the traffic performance of the advisory segment of JIUT. Data were obtained from 48 hours of traffic recording at a part of Cawang-Ancol segment. It was found that the Underwood Model (exponential model) can represent the relationship between the three main parameters of traffic flow on the advisory segment, i.e. volume, speed, and density. Based on the developed traffic flow models which are classified on the HV composition, it is shown that the free flow speed (uf) for HV composition < 6% (i.e. 144.91 km/h) is higher 35.41% than the one of HV > 6% (i.e. 107.02 km/h). The actual road capacity (qm) in HV composition < 6% (i.e. 4442 pcu/hour) also higher 12.83% than the one of HV > 6% (i.e. 3937 pcu/hour). The results will benefit to the transport authority to justify the truck access restriction implementation.

scholarly journals Estimating Passenger Car Equivalent of Heavy Vehicles at Roundabout Entry Using Micro-Traffic Simulation

2019 ◽  
Vol 5 ◽  
Author(s):  
Robert Pajecki ◽  
Faisal Ahmed ◽  
Xiaobo Qu ◽  
Xinyi Zheng ◽  
Yanqun Yang ◽  
...  
Keyword(s):  
Traffic Simulation ◽  
Heavy Vehicles ◽  
Passenger Car ◽  
Passenger Car Equivalent

scholarly journals Delay-based Passenger Car Equivalent at Signalized Intersections in Iran

2017 ◽  
Vol 29 (2) ◽  
pp. 135-142 ◽  
Author(s):  
Habibollah Nassiri ◽  
Sara Tabatabaie ◽  
Sina Sahebi
Keyword(s):  
Signalized Intersections ◽  
Simulation Software ◽  
Heavy Vehicles ◽  
Passenger Cars ◽  
Highway Capacity ◽  
Passenger Car ◽  
Highway Capacity Manual ◽  
Operational Characteristics ◽  
Passenger Car Equivalent ◽  
Traffic Operation

Due to their different sizes and operational characteristics, vehicles other than passenger cars have a different influence on traffic operations especially at intersections. The passenger car equivalent (PCE) is the parameter that shows how many passenger cars must be substituted for a specific heavy vehicle to represent its influence on traffic operation. PCE is commonly estimated using headway-based methods that consider the excess headway utilized by heavy vehicles. In this research, the PCE was estimated based on the delay parameter at three signalized intersections in Tehran, Iran. The data collected were traffic volume, travel time for each movement, signalization, and geometric design information. These data were analysed and three different models, one for each intersection, were constructed and calibrated using TRAF-NETSIM simulation software for unsaturated traffic conditions. PCE was estimated under different scenarios and the number of approach movements at each intersection. The results showed that for approaches with only one movement, PCE varies from 1.1 to 1.65. Similarly, for approaches with two and three movements, the PCE varies from 1.07 to 1.99 and from 0.76 to 3.6, respectively. In addition, a general model was developed for predicting PCE for intersections with all of the movements considered. The results obtained from this model showed that the average PCE of 1.5 is similar to the value recommended by the HCM (Highway Capacity Manual) 1985. However, the predicted PCE value of 1.9 for saturated threshold is closer to the PCE value of 2 which was recommended by the HCM 2000 and HCM 2010.

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