Overtaking Violations in Left-Turn Lanes of Rural Roads
Total Page:16
File Type:pdf, Size:1020Kb
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Repository of the Academy's Library Journal of Society for Transportation and Traffic Studies (JSTS) OVERTAKING VIOLATIONS IN LEFT-TURN LANES OF RURAL ROADS Dániel MILETICS Csaba KOREN Junior lecturer, PhD student Professor Department of Transport Infrastructure and Department of Transport Infrastructure and Municipal Engineering Municipal Engineering Szechenyi Istvan University Szechenyi Istvan University Egyetem ter 1 Egyetem ter 1 9026 Gyoer, Hungary 9026 Gyoer, Hungary Fax: +36-96-503-451 Fax: +36-96-503-451 E-mail: [email protected] E-mail: [email protected] Abstract: Overtaking is a high risk manoeuvre for road users, still driver often accept this risk, moreover often commit irregular overtaking manoeuvres. The paper gives some overview on traffic violations and irregular overtaking manoeuvres. Left-turn lanes are usual elements of at-grade junctions on two-lane rural roads. In several cases the left-turn lane, built for safety reasons, has the unintended negative effect, it becomes a dangerous spot. The paper analyses overtaking manoeuvres at left-turn lanes on Hungarian rural roads. Typical sites outside built-up area have been identified and selected. Site surveys were completed at the selected intersections and its area. The frequency of irregular overtaking manoeuvres, geometric design, traffic volume, traffic mix and speed characteristics were registered at the intersections. Accident statistics have been collected. Relationships between the frequency of irregular manoeuvres, accident statistics, geometric parameters and traffic data are analysed. Key words: driver behaviour, left-turn lane, irregular overtaking, site survey, violation 1. VIOLATIONS ON THE ROAD the varieties of aberrant driving behaviours has been conducted by Reason et al. (1990). Self- In considering the human contribution to reports of driver errors were collected through accidents, psychologists make a distinction the driver behaviour questionnaire from a between errors and violations; two forms of sample of 520 British drivers. Several other aberration which may have different studies followed this in other countries (e.g. psychological origins and demand different Kontogiannis et al. 2002, Gras et al 2006). The modes of remediation (Reason et al., 1990). most common criticism of self-reported data is Three fairly robust factors can be identified: the possibility that it suffers from social violations, dangerous errors, and relatively desirability bias. However, research using the harmless lapses, respectively. Violations require DBQ found that socially desirable responding explanation in terms of social and motivational had a very minimal effect on participants factors, whereas errors (slips, lapses, and responses (Lajunen & Summala, 2003). mistakes) may be accounted for by reference to Another common criticism of self-report is that the information-processing characteristics of there is great variance between what drivers the individual. report and their actual behaviour. However, there are also a number of studies that have As a large portion of the violations remains found self-reported driving behaviour to be hidden, it is a common method to investigate significantly related to actual driving behaviour. them by driver behaviour questionnaires The most often reported violations in France (DBQ). One of the most influential studies of are shown in Table 1 (Nallet et al 2010). Dániel Miletics, Csaba Koren Table 1. Violations reported to be committed often or fairly often in 2005 in France (Nallet et al. 2010). Men Women (n = 655) % (n = 506) % Exceeding the speed limit by 10 km/h on a motorway 55.8 48.7 Daytime excess speeding on a road 44.5 34.1 Night-time excess speeding on a road 38.0 22.5 Exceeding the speed limit in a built up area 27.1 21.4 Driving through an amber traffic light 21.6 22.0 … … … Not wearing a seat belt 9.6 5.4 Risky overtaking 8.5 5.3 Drink driving 5.7 0.9 … … … Driving the wrong way down a one-way street 2.8 0.7 Ignoring a stop sign 2.6 0.8 Among the 21 violations, risky overtaking is at perception of the risk of punishment for a rank 15, drivers report to commit this quite violation, risky overtaking stands at rank 15 rarely. This is probably because they feel this again, indicating that the risk of punishment for manoeuvre highly dangerous (see Table 2). It is this violation is quite low(see Table 3). remarkable however that considering the Table 2. Perception of the danger associated with the violations in 2005 in France (Nallet et al. 2010). Men (%) Women (%) Drink driving 87.8 90.4 Ignoring a stop sign 87.6 89.6 Risky overtaking 89.4 86.3 Cutting in front of another driver 85.0 85.9 Driving the wrong way down a one-way street 84.1 88.2 Telephoning while driving 82.7 88.2 … … … Illegal parking 35.4 36.3 Exceeding the speed limit by 10 km/h on a motorway 31.9 42.1 Table 3. Perception of the risk of punishment for a violation in 2005 in France (Nallet et al. 2010). Men (%) Women (%) Not wearing a seat belt 79.3 73.7 Drink driving 60.0 71.9 Exceeding the speed limit by 30 km/h on a motorway 57.4 66.5 Ignoring a stop sign 55.7 60.9 Exceeding the speed limit in a built up area 52.4 65.8 … … … Risky overtaking 19.5 25.5 … … … Failing to indicate 10.6 11.7 Journal of Society for Transportation and Traffic Studies (JSTS) 2. OVERTAKING STUDIES 3. DESIGN OF LEFT-TURN LANES Overtaking is a high risk manoeuvres for road 3.1. Hungary users. In the case of a head-on collision, the summarized speed of two vehicles can result a According to the Hungarian design guidelines much more severe impact. (HRS 2008), left-turn lanes have to be provided in junctions on rural roads depending on the As a type of violations irregular overtaking has expected traffic volumes of the two roads. been observed and analyzed in Saudi Arabia More exactly, left-turn lanes are required, if the through the actual behaviour of drivers (Ratrout product of average annual daily traffic of the 2004). Irregular overtaking was a frequent two roads is higher than 4.5 million cause of accidents with 10 % proportion of all (AADTmajor*AADTminor>=4 500 000). accidents. The goal of Ratrout’s study was to quantify the extent of irregular overtakings and Left-turn lanes can be implemented various to find relationships between different ways according to the traffic volume, class of geometric and traffic conditions and the major road and design speed. The usual number of irregular overtaking manoeuvres. geometric design (Figure 1) consists of three sections. First is the lane changing section (L Z), Two types of sites were selected for the which is usually implemented by pavement observations: curves and tangent sections. markings only. Second is the deceleration Overtaking was prohibited in both cases. The section (L V), third is the queuing section (L A). prohibition was communicated to the drivers In case of four leg intersection and high left only by road markings, there were no traffic turning traffic, left-turn lanes should be signs posted at any sites. While in case of implemented in both directions (HRS 2004). curves the reason is the restricted visibility, prohibition of overtaking at tangent sections Following the rules of the guideline, the length (where anyway the visibility conditions are of the left-turn lanes can be calculated as a good) is reasonable by e.g. the desirable function of the design speed (Table 4). In case avoidance of more risky traffic situations in an of left-turn lanes in both directions, the total intersection area. length of the two lanes will be between 200 and 400 m. Moreover, if the design speed is 70 It was found, that average percentage of km/h or more, this length is more than the half irregular vehicles was higher on straight of the minimal overtaking sight distance. These sections (2.3%), than at curves (1.8%). It seems lengths provide opportunity for drivers to that there is no correlation between neither the overtake in the left-turn lanes even with some alignment nor the time period and ratio of feeling of “safety”, as the vehicle in the irregular overtakings. According to the linear opposite direction is far away enough. regression model given by the study, the However, this is actually a false feeling of number of overtaking vehicles can be predicted safety. by traffic volume, namely the number of irregular overtakings is more affected by the traffic volume in the same direction, than by the traffic volume in the other direction. This model was valid between 650 and 1000 ADT in both directions. Dániel Miletics, Csaba Koren Figure 1. Usual geometric design of left-turn lanes Table 4. At design speed 70 km/h and more the total length of the two left-turn lanes is higher than the design overtaking length (see bald figures) Design speed (km/h) Design parameters 50 60 70 80 90 100 110 Minimal overtaking sight distance, Le_min, 1 360 400 440 500 560 640 700 m 2 Length of lane changing section, L A, m 35 42 49 57 64 71 78 Length of deceleration section (if AADT to 3 0 20 30 40 55 70 85 left>400 PCU), L V, m 4 Length of queuing section, L A, m 20 20 20 20 20 20 20 5 Length of left-turn lane, m 2+3+4 rows 55 82 99 117 139 161 183 Total length of two left-turn lanes and 6 136 190 224 258 302 346 391 intersection core, m Half of the the minimal overtaking sight 7 180 200 220 250 280 320 350 distance = design overtaking length , m 3.1.