Experimental and analytical justification of the asphalt concrete cutting process by road milling machines working equipment

Abstract

Introduction. The article is devoted to the results of a study of the cutting resistance of road asphalt concrete in the process of removing worn coatings by the working bodies of milling machines. The relevance of the work is due to the emergence of new grades of asphalt concrete and new types of cutting elements, for which it is difficult to predict the loads on the working body when solving the problems of designing new and justifying the operating modes of existing machines.Purpose. To calculate the parameters of the working body of the road milling machine.Materials and methods. The experimental work was carried out by determining the horizontal and vertical components of the resistance force of cutting asphalt concrete. The research was carried out on a mechanical stand with a movable plate, using recording equipment. Four different grades of asphalt concrete were destroyed. A twofactor experiment was conducted for each brand of material. The horizontal and vertical components of the cutting resistance forces were determined depending on the chip cross-sectional area, the grade of asphalt concrete and the type of cutting element.Results. As a result of the experiment, data were obtained that make it possible to reasonably determine the loads on the working body of the road milling machine. It is proved that the dependence of the cutting resistance forces on the chip cross-sectional area of the cutting element has a nonlinear character. The data obtained allow to comprehensively answer questions concerning the justification of the parameters of road milling machines.Discussion and conclusion. The obtained data allow to develop a mathematical model of the asphalt concrete milling process which will make possible to determine not only the loads on the working body and the energy intensity of the process, but also to reasonably approach the placement of cutting elements on the drum, determine the rational range of equipment operating modes and solve the problems of choosing operating modes depending on the type of asphalt concrete.