Papers by Author: Li Li Xin

Abstract: Materials present elastic-plastic deformation under cyclical loading because of the influence of vibration friction, and restoring force and the displacement show hysteretic characteristics in compacting mechanism and materials system. To further study nonlinear dynamics of the vibrating compacting system, system model with symmetric hysteretic curve was established in this paper, and was verified by experiment. Bifurcation and chaos motion were studied in nonlinear vibrating compacting system by the combination of qualitative theory and numerical solution, and analysis results show that vibration have piecewise and singular characteristics in vibrating compacting system, and hysteretic loop parameters show significant influence on system and large effect on nonlinear dynamics of system.

Abstract: Soil has elastic-plastic deformation under vibrating working condition. And the acting force between the soil and the vibrating subsoiler parts is of complication. In order to study the effect of the material acting force to the vibrating subsoiler system kinetics features, this paper establishes the vibrating subsoiler system mechanics model considering material acting force. It adopts numerical integral to answer and analyze this model and verify the correctness of the model through comparison of the simulation data and experimental data. The analysis shows that when the amplitude is between 0.01m-0.02m and the vibrating frequency is between 14Hz-16Hz, the vibrating subsoiler can have a comparatively good performance.

Abstract: It uses ADAMS software to establish the double wishbone suspension kinematics analysis model to analyze the rules of front wheel alignment parameter changing with wheel run-out and evaluate the rationality of the suspension system data. For the problem of too much side slippage and serious abrasion of front wheel of suspension, it carries out optimization computing for the suspension based on the target of minimizing the front wheel side slippage during wheel run-out. And the optimization result improves the suspension system performance in a certain extent.

Abstract: For the vibrating subsoiler, considering the material acting force, the system is simplified as a single degree of freedom weight-spring-damp model which will simulate the vibrating subsoiler system based on Automatic Dynamic Analysis of Mechanical System (ADAMS). The analysis result shows that the vibrating subsoiler can not perform well under conditions of high vibration frequency and advance speed.

Abstract: In this work, the numerical equation has been established to simulate the vibratory compaction system based on the hysteresis loop of Davidenkov and with the gap ignored between the piston and the materials, and the dynamical characteristics and influence of parameters on the vibration compaction effect were analyzed with different stiffness, damping, amplitude and mass with different water saturation. The two types of experiments were carried out to study the dynamical characteristics and validate the numerical analysis and simulation. The first type of experiments was done with the different exciting vibration amplitude. A second type of experiments was done with the different water saturation (3%, 8% and 17%) instead of the stiffness and damping. The numerical and experimental results show that the equivalent natural frequency and vibration amplitude of the system increased with the stiffness, exciting amplitude increased and damping decreased. The experimental results agree well with results from a theoretical model in general. The research results will be used in intelligent soil compaction in the future.