Study of the economical longitudinal slope of a hill bypass when tracing roads

Анотація

Problem. Taking into account the relief during tracing is mainly reduced to the longitudinal profile vertical geometry and the prevention of high embankments and deep excavations, but there are a number of other factors that must be taken into account in the design process. First of all, it is the fuel consumption as an economic factor and as an environmental factor. The designer can only control a longitudinal slope when going around a hill. Goal. The goal of the study is to confirm the hypothesis that there is an interval of the value of the source data when there is an extremum of the total fuel consumption. The source data include the depth of the excavation, the distance between the starting points, the height of the hill and the steepness of the slopes. The total cost of fuel refers to the amount of fuel that a certain group of cars will spend when driving on a specific section of the road from the starting point to the final point. Methodology. To solve the above problem, 10 variants of the highway route between point A and B have been designed with a bypass of the hill under different longitudinal slopes. Total fuel consumption has been calculated in CAD CREDO. Results. The most important result of the study is the confirmation of the hypothesis that there is an interval of the value of the source data when there is an extremum of the total fuel consumption. Originality. With a certain minimum extremum of the total fuel consumption, an economical longitudinal slope has been found. This slope corresponds to a specific group of vehicles. The vehicle compositions are one of the initial characteristics in the design of the road, so one can always determine the average economical longitudinal slope. Practical value. This slope can serve as a tactical guide for the designer when tracing in a specific area of the terrain.