The Evaluation Of Intersection's Driving Safety Based On Driving Speed

With the accelerating urbanization, the city's scale has been expanding quickly. However it subsequently also caused many contradictions and problems, such as the urban traffic congestion, traffic order confusion, frequent traffic accidents,especially more seriously in the city's intersection. How to evaluate the city's road intersection safety plays an important role in improving the intersection safety. The safety evaluation method of urban intersection is mainly based on the accident rate evaluation method, such as probability statistics method and strength analysis method,which needs a lot of time to collect and counts up traffic accidents while non-accident rate evaluation method doesn't need a lot of time,such as using traffic conflict technology evaluation method. So on the one hand, based on the research's current situation at home and abroad and speed change,the paper introduces "risk coefficient method", which evaluates the city's road intersection safety from the partial angle. This method evaluates driving safety which is based on the acceleration in the rate of change of position relatively, that means the greater the risk coefficient, the worse the driving safety at this point. In the meanwhile, based on the discreteness of driving speed increases, the traffic accident rate appears an increasing and quickly trend, comparing with patch vehicle speed discreteness' s conclusion, which in order to verify the rationality of this method. On the other hand, This paper selects three indicators named the speed, continuity and speed's difference,which in order to set up the intersection's speed safety judgment model based on Vague complex matter-element. This method evaluates the city's road intersection driving safety from the whole angle and through example analysis. The paper's content includes the following several parts:(1)Briefly describes the research's current situation about the intersection driving safety in the city and analysis the driving speed's important influence on the driving safety. Therefore, the paper considers the road intersection driving safety in the city from the angle of the speed change.(2)The method evaluates the city's road intersection driving safety based on the speed change, on the one hand, introduces "risk coefficient method" and deduces the calculation formula, which identifies the risk part in the different driving directions of the city's road intersection from the partial angle. So it confirms the different driving directions of the city's road intersection. On the other hand, based on the current research about the driving speed and security's relationship, the paper selects three indicators named the speed, continuity and speed's difference and he intersection's speed safety judgment model based on Vague complex matter-element,which judges the city's road intersection driving safety from the whole angle.(3)The paper choose the road intersection at Guangzhou Zhengjia Mall as the example. Firstly, according the research purpose, The paper determines the minimum sample size for the data collect and collect data. Secondly,it arranges and analysis the data in order to provide the data base for the road intersection's evaluation method,which based on the speed change.Thirdly, the paper not only fits the relationship with the driving speed and the distance of the patch after using "risk coefficient method",but also puts forward the risk coefficient formula. In addition, it calculates the risk coefficient of each patch in turn. So it ensures the risk part in difference driving direction and compares with the calculation conclusion through the patch discreteness' s driving speed, which on this account proves the feasibility, reliability and rationality of using "risk coefficient method". Finally, based on the intersection's speed safety judgment model from the whole angle, the paper judges the city's road intersection driving safety.