Simulation And Research Of Dense Element Process For Block Chaos Vibration Molding Based On Discrete Element Method

With the needs of social development,fast paced and high efficiency have become the mainstream features of modern society.For the construction industry,the process of "building industrialization" continues to improve.The preparation of concrete prefabricated parts is a feasible method to improve the building efficiency.Therefore,the application of concrete precast concrete parts is more and more widely used.However,the use of concrete prefabricated parts in our country is relatively less,mainly due to the relatively poor compaction of precast concrete parts,which leads to the deterioration of the strength and durability of precast concrete parts.The deeper reason is that the vibration frequency of concrete vibrating table is relatively single,Can not resonate with most aggregates.Concrete shakers as concrete prefabricated parts of the production equipment,its performance is a direct indicator of the concrete preform density and strength meet the requirements.Vibrator as the main component of concrete shaker,he has a great influence on the performance of concrete shaker.This article presents a chaotic exciter that has a wider frequency range than traditional exciters and resonates with most of the aggregates,so that the density and strength are greatly improved,and on this basis,the design and production Machined a chaotic concrete shaker,due to the rush of time,this article only chaotic concrete shaker vibration characteristics were analyzed.The specific research contents are as follows:(1)Present situation of research on concrete preform and vibration molding,research status of discrete element,concrete vibration compacting process,concrete vibration compact mechanism and related factors affecting vibration compactness are introduced.At the same time,the quantitative and qualitative methods of chaos vibration identification and chaos identification are also introduced in detail.The specific process of chaos identification is discussed.(2)The vibration mode of the traditional shaker is briefly described.At the same time,the main component of chaotic shaker-chaotic exciter is proposed and established.The chaotic vibration exciter is modeled by solid works software,then the chaotic vibration exciter is simulated by Matlab software to get its vibration characteristics.By using the chaotic vibration exciter phase diagram,Poincaré graph,self-power spectrum The density map and the calculated Lyapunov exponent verify that the exciter is a chaotic exciter.(3)Based on the established chaos exciter,a chaotic concrete shaking table is established.Using solidworks software to model the concrete shaking table,using the Matlab software to simulate the vibration table of the chaotic concrete to get its vibration characteristics.By using the chaotic concrete shaker table,the Poincaré chart,the self-power spectral density chart And the calculated concrete shale shaper established by Lyapunov exponent verification is a chaotic concrete shale shaker.(4)According to the principle of discrete element method,the compact process of concrete is verified by PFC2 D software.The comparison shows that the chaos vibration table has a greater increase in the compaction degree than ordinary single frequency vibration table,In fact,compact concrete provides the theoretical basis.At the same time,we use the signal acquisition instrument to produce the 1000x1000 chaos concrete vibrating table for signal acquisition and analysis,in order to verify our designed vibration table for the chaotic concrete vibrating table.