轨道交通桩板结构隔振效果有限元分析研究

The Research on The Vibration Isolation Effect of Pile Plate Structure In Rail Transit Through Finite Element Analysis

为了研究轨道交通荷载作用下桩板结构主动隔振措施的隔振效果,在路基模型中设置桩板结构,为了模拟振动波传播于无穷远处,通过无限元边界与有限元边界相结合的有限元分析方法建立模型,把桩长、填充率及埋深因素考虑在内,研究各因素对隔振效果的影响.结果表明:随桩长增加,隔振效果越显著,处于45度角方向存在明显的振动加强区,随着距离振源增加,振动加强区均在减小;埋深对隔振效果影响显著,随着埋深的增加隔振效果加强,隔振效果增强趋势是由45度中线区域逐步向俩侧增强,埋深小会引起隔振板对波反射,影响隔振效果;填充率因素在主动隔振桩板结构中有隔振效果,但效果不明显,随着填充率的增加其隔振效果在缓慢增长.

In order to study the effect of active vibration isolation measures of pile plate structure under rail transit load,Pile plate structure is set in the subgrade model.In order to simulate the propagation of vibration waves at infinity,the finite element analysis method combining finite element boundary with finite element boundary is used to build the model,in which the depth of vibration source,the hollow ratio of piles and the outer cross section are considered,and the effect of various factors on vibration isolation effect is studied.The results show that the vibration isolation effect becomes more significant with the increase of pile length,there is an obvious vibration strengthening zone in the direction of 45 degree Angle,and the vibration strengthening zone decreases with the increase of distance vibration source;The buried depth has a significant impact on the vibration isolation effect.As the buried depth increases,the vibration isolation effect is strengthened,the enhancement trend of vibration isolation effect is from the mid-line region of 45 degrees to the two sides gradually.The small buried depth will cause the reflection of vibration isolation plate on the wave and affect the effect of vibration isolation;The filling rate factor has the effect of vibration isolation in the active vibration isolation pile plate structure,which is not obvious.With the increase of filling rate,the effect of vibration isolation grows slowly.