Study On The Evaluation Method Of Expressway Alignment Based On Operating Speed

The expressway is a three-dimensional alignment entity which is entire seal for automobile.The operating speed of the automobiles is reflected to people at first on expressway, it is the comprehensive result of the alignment indexes, so it is high practical value to study operating speed to the evaluation method of alignment.The target of the alignment design is consistency, steady, security, comfortably.The alignment indexes are generally great of plain expreeway, and the design method of specification is based on design speed at present, this kind of design method itself has certain flaw.In this article, the characteristic is summarized and the operating speed model is set up of horizontal, vertical, and the combination based on investigated operating speed, the V85's scope is also given about each kind of alignment ( linear section, curve section ).This article has set up the evaluation criterion, and done the statistical analysis about the investigated data, so the suitable horizontal curve radius is computed through the functional relationship of the operating speed model.Finally, adopting the operating speed model and evaluation criterion and method set up in the article, this text has given the evaluation conclushion about the project instance—Beijing-Shanghai expressway.Practice has proved that it is helpful to the expressway alignment design of plain district of our country that the models and conclusion set up in the article.