WIB在动力机器荷载激励下的远场被动隔振分析

Far-field passive vibration isolation of WIB under dynamic machine loads

为研究波阻板在动力机器荷载作用下的被动隔振效果,通过数值模拟的方法,建立了动力机器基础-WIB-土体的三维有限元模型,计算分析动力机器激振作用下埋置波阻板对远场地表振动传递阻隔的效果,研究不同参数条件对波阻板隔振效果的影响。结果表明:竖向动力机器荷载作用下,在被保护体下方地基中设置波阻板对地表竖向和水平向振动具有一定的阻隔作用,整体隔振效果竖向优于水平向;调整波阻板厚度、宽度及埋深均对被动隔振效果有影响,随波阻板厚度增加,波阻板上方地表的隔振效果基本呈增加趋势;波阻板宽度增大对上方地表振动的阻隔区域有扩张趋势,达到4倍瑞利波长则会明显放大波阻板区域的地表振动;波阻板浅埋时能够有效阻隔振动波,波阻板后方地表的隔振效果明显优于波阻板上方。

In order to study the passive vibration isolation effects of wave impeding block(WIB)under dynamic machine load,a 3D finite element model for power machine foundation-WIB-soil is established by using the numerical simulation method.The effects of the buried WIB used for dynamic machine excitation on far field surface vibration transmission barrier are calculated and analyzed,and the influences of different parameters on the vibration isolation effects of the WIB are studied.The results show that under the vertical dynamic machine loads,the WIB installed in the foundation under the protected body has certain barrier effects on the vertical and horizontal vibrations of the surface,and the overall vibration isolation effects is better in the vertical than in the horizontal.Adjusting the thickness,width and buried depth of the WIB has effects on the passive vibration isolation effects.With the increase of the thickness of the WIB,the vibration isolation effects of the surface above the WIB basically increase.When the width of the WIB increases,the barrier region of the surface vibration above the WIB expands.When the depth of the WIB up to 4 times the Rayleigh wavelength,the surface vibration in the region of the WIB will be amplified obviously.When it is shallowly buried,the WIB can effectively block the vibration waves,and the vibration isolation effects behind the WIB are obviously better than those above the WIB.