Influence of technological parameters on the behaviour in operation of the asphalt milling equipment

Abstract

Within the work will be studied, in particular, the aspects related to the mechanical stresses that manifest themselves at the level of the cutter teeth used to strip the worn asphalt clothing. Studies in the field have focused on the interaction between the teeth of the milling drum and the asphalt clothing. The literature provides information and results focused, especially, on the aspects related to the way in which the dislocation of the asphalt concrete components occurs (the mixture of aggregates and filler / bitumen in solid state) under the action of the milling tooth. The authors present a method of simulating (using the combination of FEM-DEM numerical methods) of the cutting process by which it is ensured the highlighting of the developed tensions at the level of the active part of the tooth. In this way, it is attempted to bring to the fore the operating conditions specific to the milling equipment and to identify how they influence the interaction between the asphalt and the active part of the cutter teeth.

Multi-Response Optimization Analysis of the Milling Process of Asphalt Layer Based on the Numerical Evaluation of Cutting Regime Parameters

“…The technological parameters involved in the numerical analysis are presented in Table 1. Table 2 presents the elasto-mechanical characteristics of the materials used in DEM analysis [3]. The interaction between the aggregates (particles), filler/bitumen, and the milling drum is quantified using different coefficients (see Table 3), such as static friction coefficient and dynamic friction coefficient (for particle-particle and particle-tooth interactions), rolling coefficient (specific to particles), and restitution coefficient (specific to particles) [3,29,30].…”

“…The contact plane is typically perpendicular to the line connecting the centers of the particles in contact, assuming the particles have a spherical shape. The normal contact forces primarily act as repulsive forces, facilitating the dissipation of a substantial amount of energy [3].…”

“…Milling equipment for asphalt pavement is highly loaded, with the main issues being affected by the very hard-working regime determining the wear of the cutter teeth. These conditions are influenced by factors such as the mechanical properties of the material being processed (asphalt), its non-uniformity, the use of water as a working fluid to clear the work area, and the considerable cutting depth involved [3][4][5][6].…”

“…The interaction between the asphalt clothing and the milling cutter teeth during the milling process (Figure 1) is a very complex phenomenon that has been studied using numerical approaches [3,[7][8][9][10][11][12][13][14] or experimental investigations [1, [15][16][17][18]. Discrete Element Method (DEM) is a widely utilized method for studying dynamic processes, finding numerous applications in the field of asphalt pavement or soil engineering [19][20][21].…”

“…Dumitru et al [3] used a calculation method that integrated both the finite element method (FEM) and the discrete element method (DEM) to achieve precise simulation of the cutting process, enabling them to accurately determine the stresses generated within the active part of the milling tooth.…”