Research On High-speed Technology Of Two-lane Highway In Western Sichuan Plateau

This paper relies on the science and technology project of Sichuan Provincial Department of Transportation—Technical standards for high-speed highways in plateau and mountainous areas.The western plateau of Sichuan has the characteristics of sparsely populated land,small traffic volume,fragile environment,and high investment pressure.If highways are constructed in accordance with existing standards,they will inevitably result in high construction investment,low rate of return,and serious ecological damage.Therefore,from the perspective of improving road alignment geometry,reducing lateral interference,and increasing overtaking opportunities,this paper studies the high-speed technology of two-lane highway in the Western Sichuan Plateau,and achieves the goal of rapid and safe operation on the basis of regional road construction conditions.Based on the characteristics of highway construction on the western plateau of Sichuan,this paper puts forward the goal of high-speed;from the perspective of operating speed and safety,the factors affecting high-speed are analyzed,and technical measures for high-speed of two-lane highway are proposed.By analyzing the influence of plateau environment on people,vehicles and roads,based on automobile theory and dynamic principles,a calculation model of route geometric indicators is established,and recommended values of key geometric indicators for high-speed of two-lane highway at different altitudes are proposed.Through the analysis of the factors influencing the distance between access points,a calculation model for the distance between access points is established based on traffic engineering,and the recommended value of the minimum distance between two-lane highway access is proposed;through the research on the safety sight distance of intersections and the way of traffic organization,it is constructed to meet the requirements.A intersection distance model for overtaking sight distance,proposed the minimum distance between intersections;according to the operating characteristics of twolane highway vehicles,the minimum distance between access and intersections was determined;roadside interference control technology was proposed from the perspective of controlling the distance between roadside openings.According to the high-speed overtaking demand of the two-lane highway,combined with the traffic flow theory,the proportion of overtaking sections under different traffic volumes is determined.From the perspective of overtaking safety,the road alignment and traffic volume conditions for overtaking in the opposite lane in the Western Sichuan Plateau are put forward.Based on traffic simulation and theoretical analysis,the setting conditions,setting forms and geometric parameters of climbing lane,overtaking lane and 2+1 highway are studied respectively.From the aspects of safety design of two-lane roads,traffic safety measures and service facility configuration standards,the high-speed safety assurance technology of two-lane roads on the Western Sichuan Plateau has been studied.The research results of this paper provide theoretical support and technical reference for the high-speed of two-lane highway in Western Sichuan Plateau,effectively promote the planning and construction of high-speed highway in Sichuan plateau mountainous area,and also provide reference for the construction of high-speed highway in other plateau areas with sparse land,small traffic volume and difficult terrain.