摘要
基于Biot流体饱和多孔介质理论,采用波函数展开法并结合Graf加法定理,解析求解了饱和土中周期排列管桩对平面SV波的隔振问题。该方法利用饱和土中不同周期单元的散射波场在频域内仅相位不同的特性,将饱和土中无限周期排列管桩对SV波的散射问题转换为仅针对一个周期单元的求解,因而在精确求解的同时显著降低了计算量,并在一定程度上弥补了现有方法在管桩数较多时难以求解的局限。在验证方法正确性的基础上,重点讨论了桩体个数、饱和土参数、管壁厚度、桩排数和排列方式等因素对隔振能力的影响。研究结果表明:周期排列管桩在饱和土中的隔振能力整体上优于弹性土,且在渗透性越差的饱和土中隔振能力越强;管桩的管壁厚度不宜过薄,内外径之比取为0.6左右,周期排列管桩在大多数频率下隔振能力稳定;增加桩排数能够显著提高隔振能力,在无量纲频率为0~0.6的较低频段,隔振能力提高幅度为20%左右,在无量纲频率为0.6~3.0的中高频段,隔振能力提高幅度可达60%,采用三排管桩屏障可屏蔽饱和土中大多数频率下的入射SV波;管桩矩形排列的隔振效果在无量纲频率为0~1.0的较低频段优于梅花形排列,其他频段两种排列方式均具有良好的屏蔽SV波效果。
Based on Biot’s porous media theory of saturated fluid,the wave function expansion method and Graf addition theorem are used to solve the vibration isolation problem of plane SV wave by periodically arranged pipe piles in saturated soil.In this method,the scattering problem of SV wave by infinite periodic piles in saturated soil is transformed into solving only one periodic element by using the characteristic that the scattering wave field of different periodic elements in saturated soil is only different in frequency domain.Therefore,it can solve the problem of SV wave scattering by infinitely periodic pipe piles in saturated soil into solving only one periodic element limit.On the basis of verifying the correctness of the method,the influence of the number of piles,the parameters of saturated soil,the thickness of pipe wall,the number of piles and the arrangement mode on the vibration isolation capacity are discussed.The results show that:(1)the vibration isolation capacity of periodically arranged pipe piles in saturated soil is better than that in elastic soil,and the vibration isolation ability is stronger in saturated soil with poor permeability;(2)the thickness of pipe wall should not be too thin,and when the ratio of inner diameter to outer diameter is about 0.6,the vibration isolation capacity of periodically arranged piles can be stable at most frequencies;(3)increasing the number of piles can significantly improve the vibration isolation capacity,which can be increased by about 20%in the low frequency range of dimensionless frequency 0-0.6,and 60%in the medium and high frequency range of dimensionless frequency 0.6-3.0;(4)the vibration isolation effect of rectangular arrangement of piles is better than that of plum shaped arrangement in the low frequency range of dimensionless frequency 0-1.0,and the other two arrangements have good shielding effect.
作者
巴振宁
刘世朋
吴孟桃
梁建文
BA Zhen-ning;LIU Shi-peng;WU Meng-tao;LIANG Jian-wen(Key Laboratory of Coast Civil Structure Safety,Ministry of Education,Tianjin University,Tianjin 300350,China;Laboratory of Earthquake Engineering Simulation and Seismic Resilience of China Earthquake Administration,Tianjin University,Tianjin 300350,China;Department of Civil Engineering,Tianjin University,Tianjin 300350,China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2021年第3期627-637,共11页
Rock and Soil Mechanics
基金
国家自然科学基金资助项目(No.51778413,No.51578373)
天津市研究生科研创新项目(No.2019YJSB176)。
关键词
饱和土体
管桩隔振
周期排列
波函数展开法
平面SV波
saturated soil
vibration isolation of pipe piles
periodic arrangement
wave function expansion method
plane SV waves
作者简介
第一作者:巴振宁,男,1980年生,博士,教授,主要从事地震工程与工程波动方面的研究。E-mail:bazhenning_001@163.com。
