Study On The Compaction Mechanism Of The Hydraulic Single Steel Wheel Vibratory Roller

With the continuous development of vibration compaction technology,higher requirements of the compaction effect, comfort and reliability are put forward.The key factors affecting the performance lie in the proper values of the vibration parameters.The compaction work is mutual coupling process of machinery and working medium,and also is a complex physical and mechanical process. In order to further research the essence of compacting, the topic,with the machine-soil system as the research object, with their interaction as the basic starting point, adapts the method of combining theoretical analysis,simulation analysis and experimental research to probe into the change law of dynamic of vibration parameters and compaction effect.The characteristics of soil compaction are analized, and the deformation process of soil in the lag stage, the elastic-plastic stage and elastic stage is different.Density of soil mainly lies in the plastic deformation, thus the energy point of view is put forward from the consideration on the soil structure and the vibration transfer rate and absorption power are considered as a indicator measuring the compaction effect of soil in the thesis.Sensitive characteristics of vibration parameters on the working medium are discussed:roller working amplitude is affected by crushed materials and presents certain regularity.According to the established mathematical model, relationship between the amplitude and the working medium, the phase difference between wheel and rack, the vibration frequency and load of walking system are quantitatively analized.Numerical relationship between the working amplitude and nominal amplitude and amplitude frequency characteristics of the nominal amplitude are analized,and compared with the field test results,to validate the rationality of the mathematical model.Through the establishment of six degrees of freedom of the machine-soil dynamics model, combining with the state space method,simulation analysis are carried out with MATLAB/Simulink.Pendulum vibration and jump vibration characteristics are analyzed. The pendulum vibration affected not only by the structure of the machine, also changes of the working medium and frequency and present some regularity. The causes of jump vibrationfrom two aspects:static displacement and the effective force are analyzed,and the measures to reduce the jump vibration are put forward.With vibration transmissibility and soil absorption power as the double objective function, non-linear optimization model is established.Using MATLAB to conpile M file, the key technical parameters of roller the amplitude, frequency and mass ratio of hop and off roller are simulated and optimized.The optimization results are analized and the results show that the optimization result is reasonable,which provides a certain theoretical significance and practical value for single drum roller parameter design, and the influence laws of the vibration parameters(frequency, mass ratio of hop on and off) and soil parameters on the vibration transmissibility and soil absorbed power are contrasted and analized.