Based On DEM-simulation Of Asphalt Mixing Sieve Screening Efficiency Estimation And Experimental Research

Shale shaker is a core component of asphalt mixing equipment pre-treatment process. The screening efficiency and reliability directly affect the life of the asphalt pavement. The representative research on the screening efficiency was described in the paper, and the auther focused on the study of asphalt mixing equipment multi-layer linear shale shaker screening efficiency. The numerical method-discrete element method was introduced into multi-screen screening process research, and the authenticity and reliability of the numerical simulation was verified by the field experiment. The auther researched how the screening efficiency of multi-layer linear shaker varies along with the vibration frequency、amplitude、vibration direction angle and screen surface angle by controlling the variable method, which provided the reference for the design of the multi-linear vibrating screen.Firstly, the basic principles and methods of computation of discrete element method to choose the material particles and particles were studied, which were able to determine contact judgment method of particles with particles and particles with the screen. The calculation method of the contact force was explained. The three-dimensional solid model simplified was imported into discrete element simulation software EDEM, the model parameters of the shaker were set in accordance with the actual conditions. The simulation reproduced many typical motion state of the particles flow on the screen surface and the sieving motion state. Aslo, the screening results are statistics.Secondly, this paper proposed a calculation method considering the screen size fraction distribution in continuous high-volume production, which were able to obtain on each sieve composition of materials, quality, and grain size distribution of the proportion of undersize material things, reflect the real situation of the real work of the shaker, multi-layer capable of screening efficiency measured shale shaker asphalt mixing efficiency calculation methods. Meanwhile, the screening efficiency calculation method proposed in this paper was achieved on the basis of experimental data programmed automatic solution more operational than traditional methods, significantly reducing the amount of human calculation, unlimiting the number of layers, which can be used for multi-layer linear shaker screening efficiency calculations.Finally: With EDEM simulation software for multi-group sieving, screening efficiency values obtained with layers of vibration frequency, vibration direction angle, amplitude and angle of the screen surface vibration parameters trends. According to the results of simulation, it can be concluded that each screening efficiency are not the same, showing a more complex nonlinear relationship. Mapping relationship between vibration parameters and screening efficiency by building the BP neural network, then predicting screening efficiency under the vibration parameters within the specified range by BP neural network completed, which provided a reference for the design of multilayer linear shale shaker.