Results for "traffic accident" : Scipedia

Collection of open thesis in transport research

Heavy vehicles and safety in horizontal curves highway design.

Abstract

curvas horizontais das rodovias notoriamente colecionam acidentes de trânsito, nos quais geralmente os automóveis derrapam e escapam pela tangente, enquanto que os veículos pesados costumam tombar lateralmente. Os critérios consagrados de projeto geométrico das curvas, consideradas planas, ignoram a propensão dos veículos pesados ao tombamento lateral, confiando apenas nas forças de atrito lateral e na superelevação transversal da via para a manutenção do veículo em trajetória segura. O presente trabalho pretende desenvolver modelo de projeto que forneça margens de segurança tanto contra o escorregamento e o tombamento lateral de veículos pesados (semi-reboques) em curvas horizontais com greide descendente. O modelo proposto no presente estudo é sensível a fatores de segurança intrínsecos e extrínsecos aos veículos, incluindo características geométricas longitudinais e transversais da pista, e a variação da trajetória do veículo dentro da curva. Os resultados obtidos demonstram que os critérios de projeto atuais não garantem a segurança de semi-reboques em curvas descendentes de raio mínimo, principalmente nas curvas de menor velocidade. O critério desenvolvido permite o estabelecimento de margens de segurança para a regulamentação de velocidade em curvas horizontais descendentes já existentes, bem como possibilita a determinação da velocidade de projeto segura para curvas descendentes em novas vias. The grade effect on highway horizontal curves is notorious for traffic accidents because automobiles tend to skid and leave the road whereas commercial loaded vehicles tend to roll over. The standard criteria for the geometric design of these curves, which are considered flat, ignore the heavy vehicles propensity for rollover by relying solely on the forces of lateral friction and on the road superelevation in order to keep the vehicle in a safe trajectory. The current study has been set out in order to develop a model that will yield margins of safety to prevent skidding and rollover of heavy vehicles (semi-trailers) on horizontal descending highway curves. The model proposed in the present study is sensitive to safety variables both intrinsic and extrinsic to the vehicles, including longitudinal and transversal characteristics of the road, and vehicles trajectory variations at horizontal curves. The results of the study show that the currently adopted safety guidelines do not guarantee the safety of such articulated vehicles on grade curves with minimum radii, mostly at lower speeds curves. As a result, the proposed criteria allows the establishment of margins of safety that can be applied to regulatory speed signs on existing horizontal descending curves, and for the setting of safe design speeds for descending curves on new highways.

Abstract

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Emer Tucay Quezon's personal collection

Analysis of Road Traffic Accident Related of Geometric Design Parameters in Alamata-Mehoni- Hewane Section

Abstract

Geometric design deficiencies on existing roads would lead to a potential accident, such as an accident that happens at the sharp curves, layered pavement conditions, and slippery pavement surface. A road traffic accident has been increasing in the Southern Region of Tigray, of which this area was shown to have alarming rates. According to the Southern Tigray Regional Police, a high figure of road traffic accidents was recorded in Alamata, Mehoni, and Hewane districts. This research study focused on the analysis of traffic accidents related to geometric design parameters of the existing asphalt road. While the data for the analysis covered route data, traffic accident reports from the police station containing some injuries, crashes, and damage to properties, as well as interviews and questionnaire surveys to people who are directly involved in road travels, are considered. The primary data have mainly covered the geometry of the road which was measured during the site survey, road safety audit using the checklist, interview, and questionnaire survey. On the other hand, the secondary data collected from the traffic management office in the district offices. On this, the results presented in the form of line graphs, pie charts, figures for road traffic accidents, and sketches for the suggested improvement in the road design problem. Based on the results of the study in the year 2010 to the year 2015, it found out that there were 866 Road Traffic Accidents have been occurring in the vicinity of the survey road sections. From this figure, the road traffic accident and damage to properties expressed as an equivalent amount of about 33,565,122.00 Birr. It revealed that the primary cause of road traffic accidents in the study area emanated from the road design elements due to some geometric deficiencies in the traffic accident-prone areas. Therefore, this study concluded that the frequency of occurrence of road traffic accidents and the figure of casualties is significantly increasing. This road accident would persist if the concerned agencies do not adequately address the malady.

Abstract

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Emer Tucay Quezon's personal collection

Identification of Road Traffic Accident Blackspot locations and its countermeasures in Oromia Region, East Wollega Zone

Abstract

One of the inputs for the economic development of a country is the expansion of the road network, which is important for the transportation of people and freights from place to place. With this expansion, the occurrences of a road traffic accident is increasing in all parts of the world from time to time, killing the lives of many peoples and damage to properties. This problem is growing with the highest rate in sub-Saharan African countries like Ethiopia. The general objective of this study is to identify the hazardous locations of road traffic accidents and suggest countermeasures to mitigate the occurrence of road accidents. The study area was conducted in the East Wollega Zone of the Southwestern part of Ethiopia in the Oromia Region. Districts exposed to high traffic volume are sampled using the purposive sampling method. Those sampled districts include Digga, Sibbu Sire, Nekemte town, Wayyu Tuka, Guto Gidda, Gobbu Sayyo, Leka Dullacha, and Jimma Arjo. Road accident data are collected from all administrative districts from September 2012 to June 2015 (2005 -2007 E.C), and it was used for the analysis. In addition, a field survey was made to observe the existing geometry, an environment of the roadside, traffic flow regulators, and markings of the road sections. To rank each of the sample districts, evaluation of Priority value had been used consisting of a number of deaths, minor and major injuries that occurred for three years. Based on these parameters, each of the districts was listed from highest to lowest (i.e. Digga, Nekemte town, Sibbu Sire, Wayyu Tuka, Guto Gidda, and Gobbu Sayyo) out of the whole sample districts. This research study had found out that there was a significant increase in terms of the number of deaths occurring due to road traffic accidents as a result of the increase in the coverage of road crashes and their consequences. The major causes of road accidents include over-speeding, ignoring warning posts, road geometry, deterioration of pavement, and roadside environment. In order to minimize the frequency of road traffic accidents at the identified hazardous road locations, countermeasures are recommended, addressing to the concerned agency which includes speed breakers, installation of guardrails at curvatures, installation of hazard light to minimize night-time road accidents, removing roadside obstructions, repair, and maintenance of pavement defects to restore to as-is good condition and building additional facilities for pedestrians in an urban area.

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