Transportation Stability Of The Sacking Material Package System

The main forms of bulk solid materials are powder,granular,lump,etc.Bulk commodities such as grain,feed,cement,and chemical raw materials can be regarded as bulk solid materials.These materials are widely used in agricultural production,civil engineering and construction,chemical processes and national defense.As one of the most common ways to transport bulk solid materials,bagging method has the advantages of simple packaging form,easy storage and wide range of applicable materials.During the transportation of bulk material packages,companies often use stacking to improve vehicle transfer efficiency and reduce business costs.However,the stacking system is prone to problems such as extrusion breakage and sliding falls under continuous and complex transportation conditions.These can threaten the safety and reliability of the bales during transportation.This paper takes cement bale stacking system as the research object,firstly,the mechanical characteristics of cement bales are theoretically modeled and experimentally studied,and the dynamics of the bale stacking system is analyzed,based on which the transport stability of the stacking system is studied.The main research work and results are as follows:(1)The mechanical intrinsic model of the cement bale was established.The uniaxial static compression experiments of the cement bale were designed under the guidance of the similarity criterion of the model test,and the mechanical properties of the model cement bale were obtained through the analysis of the experimental results.Based on the viscoelastic properties of cement bales,three mechanical models,namely,the linear elastic model,Maxwell model and Kelvin model,were analyzed to reflect these properties,and the Kelvin model with the best fit to the experimental results was finally adopted to describe the actual force conditions of the bales during transportation.Finally,based on the three-dimensional force analysis of cement bales,a bale simulation model was established to verify the feasibility of using this analysis method to simulate the force conditions of cement bales.(2)The dynamics model of the stacked bale system is established and the simulation model is constructed and solved.Solution of double-layer transverse stacked beams with friction by fourth-order run-cut method,in addition,for the double-layer vertical stacking bale system,the response expression is obtained by theoretical derivation.The kinetic equations of the multi-layer bale stacking system were derived on the basis of the double-layer bale stacking system,and the simulation model of the double-layer bale stacking system was prepared by Simulink,which laid the foundation for the subsequent study of the bale stacking and transportation system.(3)Modeling of stacked bale transportation system.Introducing the virtual prototype technology in the engineering field,the longitudinal main beam,body and tire subsystem models of the lorry were constructed with the help of ADAMS/CAR,and the flexible coupling modeling of the whole vehicle model in the hybrid coordinated system method,and the digital models of random roads and bump roads were established,and the vehicle-road coupling model was obtained on this basis.(4)Simulation and results analysis of the stacked bale transportation system model were carried out.Considering that the road conditions for transporting cement bales are rugged and changeable,in order to obtain the operation status of the vehicle under different road conditions,ADASM/CAR simulation was used to obtain the acceleration variation in each direction when the vehicle was driving on the rugged road and the bumpy road,and on this basis,joint simulation was conducted with Simulink.By comparing the differences of the root mean square values of the vibration acceleration in each direction of the cement bales under different test conditions,it is concluded that a lower speed should be chosen when the road condition is poor,and the vertical acceleration has the greatest influence on the stability of the bale transportation system.