The Rationality Analysis Of Mountainous Expressway Flat Vertical Alignment Design

With the rapid development of mountainous expressway, the restrictive effect of the natural conditions along the road results in a more difficult mountainous expressway alignment design and the location of the improper road alignment design can easily lead to traffic accidents. Mountainous Expressway Alignment Design is mostly conditioned by the surrounding terrain and geological conditions, so it would appear improper combination of plane and vertical design, which seriously jeopardizes the safety of car driving. China's current technical standards stipulated in road plane, vertical and combination of both design, is now expertly used in plain hill area expressway, while the mountainous expressway construction has just started, a lot of technical criteria is based on plain hill area highway design standards. At the highway alignment design, the designer with no rules can not control plane and Vertical Alignment combination of road horizontal and vertical alignment design. Therefore, the study of combination of plane and vertical alignment design, the reasonable control of the plane and vertical alignment design standards in the combination of sections and ensuring road safety is essential, and at the same time is the urgent practical problems which need to solve.The paper by collecting a large number of relevant data, and based on home and abroad research theory study and analyze statistically the combination of plane and vertical alignment design in mountainous expressway and the values of it within the combination road sections. By collecting The design information of the test section, based on the principles of plane and vertical combinations, select the corresponding test sections; Through the analysis of the accident data and the combination of acceleration in the combination road sections, determine principle that the study of he combination of plane and vertical alignment design in mountainous expressway should make acceleration as controlling factors.This paper analyzes the force state of vehicles in the combination road sections, and partly study concretely driving force situation when the vehicles is running on the plane and vertical road. Car plane and vertical stress state synthesis appeared in the plane and vertical road design, therefore, the model of traffic synthesis of linear acceleration in the combination road sections is proposed. Using the methods of mathematical statistics, do discrete processing for the value of synthetic acceleration by the model, establish the relationship between road traffic accident data and discrete values of synthesis of synthetic acceleration in the combination road sections. Combine design information and traffic data in the test road section, verify the correlation between discrete values of acceleration and the number of traffic accidents in the combination road sections, can realize the value of synthetic linear combination of road designed to carry out a qualitative assessment.