Passenger Car Equivalents for Heavy Vehicles at Roundabouts. a Synthesis Review

Abstract

Passenger Car Equivalents (PCEs in the following) are used to transform a mixed fleet of vehicles into a fleet of equivalent passenger cars and to analyze capacity and levelof-service of roads and intersections. Most roundabouts guidelines propose constant values for PCEs but a single PCE value can result improper under heterogeneous traffic conditions. PCEs should be vary with traffic and road conditions and consequently PCEs applied to undersaturated traffic conditions can overestimate the heavy vehicle effect or be not sensitive to the traffic level or characteristics of heavy vehicles. Compared to other at-grade intersections, the interaction between the operational performances of the heavy vehicles and the geometric features at roundabouts can produce significant impacts on the heavy vehicle paths and traffic operations due to the curvilinear nature of the roundabout design. Literature presents various methods of estimation to obtain PCE values for heavy vehicles. The focus of this paper is to review statistical methods and traffic simulation studies based on microscopic approaches used to calculate PCEs for heavy vehicles driving roundabouts. Effects on capacity and estimates of PCEs based on models currently employed in roundabout analysis are also compared. The results obtained in this study aim at providing an overview of the existing knowledge concerning the estimation of PCEs at roundabouts and can represent a guideline for transportation engineers in planning, design and capacity analysis of roundabouts that operate under conditions of mixed traffic.

Kinerja Lalu Lintas Berdasarkan Okupansi, Komposisi Kendaraan pada Bundaran Tirosa Kota Kupang

“…EMP harus bervariasi disesuaikan dengan kondisi lalu lintas dan jalan sehingga emp dapat diterapkan pada kondisi lalu lintas yang tidak jenuh. Dibandingkan dengan persimpangan sebidang lainnya, interaksi antara kinerja operasional lalu lintas campuran dan fitur geometrik di bundaran dapat menghasilkan dampak yang signifikan pada jalur kendaraan berat dan operasi lalu lintas karena sifat desain bundaran yang melengkung [4]. Bukti empiris menunjukkan bahwa struktur pola lalu lintas membuat kondisi operasional di jalan raya, jalan raya dan persimpangan jauh dari kondisi ideal seperti yang dijelaskan oleh Manual Kapasitas Jalan Raya [5] [6].…”

Estimation of Passenger Car Equivalents for Two-Lane and Turbo Roundabouts Using AIMSUN

“…With specific reference to roundabouts it should be noted that little information from specialized sources and published studies is still available on calculation of PCEs; see e.g., Giuffrè et al (2019), Pajecki et al (2019), Macioszek (2012), (Fortuijn, 2009a), Brilon (2005). The Highway Capacity Manual 2000, Highway Capacity Manual (2010), and Highway Capacity Manual 2016propose PCE values for heavy vehicles equal to two for all types of roundabouts.…”