高铁路基振动压实机-土耦合系统动力学分析

DYNAMIC ANALYSIS OF VIBRATION COMPACTOR-SOIL COUPLING SYSTEM FOR HIGH RAILWAY FOUNDATION

  • 摘要: 压路机连续压实系统根据振动压实过程中振动轮响应评价压实质量,并根据土体压实质量反馈调节压路机工作参数。基于集中参数模型引入塑性弹簧,将压实过程分为弹性、弹塑性、分离三阶段;分别建立三阶段动力学控制方程,依据轮-土相对位移与作用力确定各阶段切换条件;采用现场实测数据验证模型可靠性;揭示激振力特性(激振力幅值、激振频率)和土体参数的振动响应规律。结果表明:激振力幅值不变时,振动轮振幅和分离周期随激振频率的增大而减小。激振频率不变时,振动轮振幅和分离周期随着激振频率的增大而增大。当激振力幅值与激振频率不变,振动轮振幅随着土体动剪切模量的提升而降低,土体动剪切模量较小时,土体以塑性变形为主。土体动剪切模量较大时,土体以弹性变形为主,振幅缓慢下降,直至趋于平缓。

     

    Abstract: The continuous compaction system is used to evaluate the compaction quality according to the response of the vibration wheel in the process of vibration compaction, and the working parameters of the roller are adjusted according to the feedback of the soil compaction quality. Based on the lumped parameter model, a plastic spring was introduced into the compaction process, which was divided into three stages: elastic stage, elastic-plastic stage, and separation stage. The dynamic control equations of three stages were established, and the switching conditions of each stage were determined according to the relative displacement and force of wheel-soil. The reliability of the model was verified by field-measured data. The characteristics of excitation force (amplitude of excitation force, frequency of excitation) and the vibration response of soil parameters are revealed. When the amplitude of excitation force is constant, the amplitude and separation period of vibration wheel decrease with the increase of excitation frequency. When the excitation frequency is constant, the amplitude and separation period of vibration wheel increase with the increase of excitation frequency. When the amplitude of the excitation force and frequency remain unchanged, the amplitude of the vibration wheel decreases with the increase of the dynamic shear modulus of soil. When the dynamic shear modulus of soil is small, the soil experiences mainly plastic deformation. When the dynamic shear modulus of soil is large, the elastic deformation of soil is dominant, and the amplitude decreases slowly until it becomes gentle.

     

/

返回文章
返回