基于速度特征指标的高速公路线形一致性综合评价

为量化评价已建和拟建高速公路交通安全性,以实测运行车速数据和事故率数据为基础,根据公路空间属性的变化,采用不定长法进行路段划分。考虑不同路段车速协调性和连续性的需求,引入客货差极差比、车速降低系数、路段车速离散度等车速特征指标。通过对运行车速特征指标与事故率的相关性分析,采用多元回归的方法建立了高速公路线形设计一致性综合评价模型,同时结合事故多发点改善效果的显著性,确定我国高速公路安全性服务水平,在此基础上提出线形设计一致性评价标准和评价方法。太旧高速公路的实例应用结果表明,该方法可准确有效地评价线形设计一致性。

Comprehensive evaluation of the highway alignment consistency based on the driving speed index characteristic features

The paper is intended to present a comprehensive method for evaluating the traffic and transportation safety for highway construction.For the said purpose,we have done experiments with the different highway-aligning joint sections of 4 lanes,6 lanes and 8 lanes at home in China.At the same time,we have also collected and analyzed the operating speed data of the passenger cars and trucks via laser velocimeters and radar meters.In accordance with the various road spatial geometric features for the horizontal and vertical alignment manners,the road segments can be divided with the so-called un-limited length method.In doing so,first of all,we have introduced the range ratio of the driving speeds between the passenger cars and cargo trucks for evaluating the speed dispersion from the point of view of the traffic flow embodiment through a comparison of the difference of the various speed characteristic indexes.At the same time,the speed reduction coefficient and the degree of the speed dispersion on the road sections have also been worked out based on the impact of the speed coordination and speed continuisness on the traffic safety.Secondly,we have chosen to take the operating speed characteristic indexes as the consistency evaluation variables of road-aligning system design,so as to make the crash rate as the quantitative indexes of the road safety.The relationship of such indexes can then be analyzed with the related statistical method,whereas the aligning-design consistency comprehensive evaluation models of highways can be brought into by using the multiple regression method.And,thirdly,the 3 safety service levels of the highway system can be determined based on the crash rate along with the improvement effect of the accident black spots.Thus,it has been made successful for us to propose the corresponding design-aligning consistency evaluation standards and methods based on the speed-operating characteristic indexes.And,last of all,it has been made possible to bring the results achieved into an actual Taijiu Highway operation system.Furthermore,we have recommended to bring some sets of deceleration facilities and guiding signs to amelioration of the traffic safety control levels.The actual application tests demonstrate that the evaluation results are consistent with the actual crash rate,and in turn favorable to heighten the efficiency and effetiveness of the aforementioned method in the actual application.