Analysis Of Traffic Factors And Modeling On Driving Reliability Evaluation In Raining Environment

Development of industry of the automobile and transportation, propels the social economy forward, meanwhile, causes traffic accidents to occur which seriously imperils social public security. Because of the serious traffic safety situation, it is important and urgent researches to analyze characteristics of the traffic accidents, control the frequency of the traffic accidents, and decrease the damage of the road traffic accidents. Factors that affect the traffic safety are various, for example, human, vehicle, road, environment and traffic management level and so on. Up to now, domestic and foreign researches on traffic accidents pay more attention to merely one or several factors, while less attention to the environmental harmony, even neglect the important role that the environmental factors play in. For instance, road factors provide guarantee for safe driving and its feature is relatively static, but because of the influence of the climate and exterior environment factors, makes it turn into a dynamic factor in the constant traffic environment. As a result, increase the complexity of the traffic research.Disastrous weather that affects the road traffic safety primarily has the wind, rain, fog, snow and high or low temperature and so on. Because that the road network has improved step by step and the bad weather conditions grow gradually, the traffic accidents caused by bad weather are increasing. Statistics show that there are fifty percent of the road traffic accidents, seventy one percent of the sever accidents and sixty five percent of the direct economical loses have been caused owing to the bad weather. So researches about the traffic accidents prevention in bad weather conditions are urgently needed.With the diversification of research field on the traffic safety, research about key technology of traffic accidents causation mechanism in bad weather conditions need to be deeply develop, The raining in many bad weathers conditions not only easily causes optical illusion of drivers about objects around the vehicles because that it has some characteristics of common, unexpected and localized, but also has important influence on vehicle and road performance, so the dissertation analyses traffic factors in raining environment, puts emphasis on modeling technology of driving reliability and presents prevention system and concrete improved measures. The researches will have high application value for effective decreasing traffic accidents occurred in bad weather and can play an important role in other relevant researches.Firstly, the dissertation elaborates and compares on the composition of the traffic system, approaches of system security analysis and analysis indicators of accidents, makes a classification about the traffic accidents in rainy days by the accident case studies. On this basis, it deeply analyzes the changes of the main factors of traffic system in raining environment and safety mechanism, and uses grey system theory to do a quantitative analysis about how factors in bad weather can influence the driving reliability and its contribution to the effect, and finally draws an appropriate conclusion.Then it elaborates the Principal Component Analysis method about calculating, sample processing and selection method of principal ingredients of sample in the details, and uses the method to analyze the factors that affect the driving reliability. The dissertation makes sure that five parameters that are the vision, consciousness, the ability of responding to the environment, concentration level and impatient as the driver reliability indicators, four parameters that are speed of the vehicle, the vehicle's braking intensity, the steering wheel's corner and acceleration as the vehicle reliability indicators, five parameters that are friction coefficient, flatness, drainage, water film thickness and the road alignment as the road reliability indicators. On the base of analyzing the characteristic of the various technology indicators in the rainfall environment, part of the key technology indicators are quantified by experiments. According to reliability factors of the driver, the vehicle and the road, the original data are obtained by investigation, then the sample data are gotten by the statistical analysis; and Principal Component Analysis method is adopted to calculate the data, which transforms many linear dependence indicators into few integrated indicators with linear independent, consequently finds the seven indicators with high contribution rate to driving reliability in raining environment and accumulated contribution rate of meeting requirement,.which is basis of driving reliability evaluation model.In the process of the diving reliability modeling, the dissertation adopts driving reliability of traffic system in the rainfall environment as research objective, on the basis of basic reliability concept, content of the researches, reliability indicators, the typical model of reliability, presents driving reliability evaluation model and elaborates modeling and calculation process in detail by analyzing intrinsic relationship, and researching reliability analysis methods and difference on research precondition, methods, content of system reliability in complex road condition. In order to explore applied value of the methods, typical roads are chosen to carry out the research (containing comparison experiments) measurement devices are used to collect data and analyze aiming to main indicator, multifarious methods are adopted to evaluate reliability of real transportation system, which provides practical scheme for establishing the early warning theoretical system of transportation system safety in bad weather based on reliability evaluation.Finally, Failure Tree Analysis Theory is adopted to establish the prevention system of traffic accidents in rainfall environment. On the basis of elaborating the relevant theory of Failure Tree analysis, the accidents occurred in running process of rainfall environment are ensured as the top event, by utilizing the inference method to find out the reasons and effects of the accidents occurrence, till the basic events, consequently failure tree of traffic safety system in rainfall environment is established. By referring to related disciplines theories, hierarchy structure model of road traffic accidents prevention in rainfall environment is established, which point out the way forward for scientifically systematically researching traffic safety measure in bad weather condition. Aiming to rainfall, specific safety measure are analyzed from several facets that is the driver's behavior tactics, the vehicle' running behavior pattern, the road deign and the plan completion respectively.The dissertation through a deeply understanding and analyzing on the road traffic causing factors in rainfall environment inheriting the domestic and foreign advance study, on this base combines the specific circumstance of the practical cases, and chooses a suitable job breakthrough and in certain extent provides a new idea and method for the research work in the scientific field. On the base of deeply and careful study work, and the use of advanced equipment to get the first hand information of research, it formulates a research scheme of flexibility or combing with a variety of theoretical knowledge to make a detailed study on the subject. It intends to do a all-round exploration about the interior regular of the road traffic system in bad weather conditions, enriches the ways of the road traffic safety theory and practice, provides a practical security guarantee for a continues healthy development of the road transportation system.The innovative research results are as followings:(1) Using grey relative technology to analyze the importance degree between driver, vehicle and road factors, it is of great significance to establish the weight between them.(2) Through a large amount of literature, field study, and survey means to obtain the factors which have a remarkable influence on the driver reliability in the rainfall environment, propose appropriate evaluation indicators and establish basis for the research work.(3) Applying the principal component analysis method to argue about the drive reliability in rainfall conditions, transforms many linear dependence indicators into few representational linearly independent indicator, find the indicators with high contribution rate to driving reliability in raining environment and accumulated contribution rate of meeting requirement.(4) Putting forward to a practical way for the study in this area by proposing the evaluation model for drive reliability in the rainfall environment and turning qualitative analysis to quantitative study.(5) On the base of the failure tree analysis, it proposes the hierarchical structure model of road traffic accidents prevention in the rainfall conditions, which is a great significant for the comprehensive study about the traffic safety measures in rainfall environment.In conclusion, a new idea and method is provided for the formation of the road traffic safety theory and further study by the way that integrates systematization, theoretical definition and practice, and carrying out the study about the analysis of traffic factors in the field of road traffic safety, driving reliability modeling, and theory, method, and practical technology of accident prevention.