Study On Assessment Technology Of Expreesway Alignment Based On Principle Of Entropy

Alignment level of design plays a deterministic roll in the safety traffic, through thesafety evaluate of alignment, we will find the insufficient of the alignment design, and reducethe potential safety hazard.Thus,It’s of great theoretical value to study on the safety evaluationsystem of highway alignment.And to evaluate the interaction between safety indicatorsquantitatively.The text tries to applies the entropy thought to the safety evaluate of alignment,take various factors into consideration and make the evaluation results more objective andcomprehensive.The main content of this paper is described as follows.At first, this text has analyzed a great deal of methods to study the line shape and trafficsafety both at home and abroad systematically, analyzed the deficiency of the existing designtheory and method, lay the foundation for the establishment of the evaluation model.Secondly, the evaluation indicators of linear comfort, linear safety and speed continuityare raised through studying the relationship berween operating speed and traffic safety. Andby analyzing the relationship among traffic safety and road alighment, the operating speedprediction model which is applicable to highway is created with the operating speedprediction model in theory and existing.Thirdly, the comprehensive effects of each indicators towards road alignment safety isdiscussed using entropy analysis model. And the grading standards of road alignment safetyevaluation is built by introducing the fuzzy mathematics, therefore, a complete comprehensiveevaluation model of road alignment safety can be drew.At last, applying the comprehensive evaluation model of road alignment into engineeringpractice, and forecasting the operating speed using route designation data. Above all, thesafety indicators of each evaluating road section are calculated, and the indicators are alsoanalyzed in quantitative using comprehensive evaluation model. According to the evaluationstandard, obtained the poor sections, the model is proved the feasibility of application,provided a certain theoretical basis for the improvement of expressway alignment.