径向振动激励对饱和砂土的扰动特征试验研究  

Experimental study on the disturbance characteristics of saturated sand under radial vibration excitation

作　　者：李晓龙[1,2] 陈永利 肖伟帆 马鹏 钟燕辉 张蓓[1,2] 王复明 LI Xiaolong;CHEN Yongli;XIAO Weifan;MA Peng;ZHONG Yanhui;ZHANG Bei;WANG Fuming(School of Water Conservancy and Transportation,Zhengzhou University,Zhengzhou,Henan 450001,China;National and Local Engineering Laboratory of Major Infrastructure Detection and Rehabilitation Technology,Zhengzhou,Henan 450001,China;Henan Luhun Reservoir Administration,Luoyang,Henan 471032,China)

机构地区：[1]郑州大学水利与交通学院,河南郑州450001 [2]重大基础设施检测修复技术国家地方联合工程实验室,河南郑州450001 [3]河南省陆浑水库管理局,河南洛阳471032

出　　处：《岩石力学与工程学报》2024年第9期2289-2300,共12页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(52178401);河南高校科技创新团队支持计划(23IRTSTHN014);河南省2021年水利科技攻关项目(2021-72)。

摘　　要：为研究径向振动激励对饱和砂土的扰动效应,研发一种具有径向激振功能、频率可调的振动试验系统,利用该系统开展振动频率10~50 Hz条件下饱和砂土扰动试验,分析径向振动激励对饱和砂土扰动效应时空演变规律和分布特征。结果表明,在试验工况范围内,受振动激励作用,各测点孔隙水压力前期逐渐上升,达到峰值后逐渐下降并趋于稳定;随着振动频率的升高,饱和砂土受扰动程度更加剧烈,各测点超静孔隙水压力、超静孔隙水压力比、液化持续时间及振动加速度逐渐增大;振动频率为30 Hz时,部分测点达到液化状态,40和50 Hz时,所有测点进入液化状态;随着深度增加,振动过程中各测点孔隙水压力越大,达到峰值时刻越早,液化持续时间越短;振动器中部附近土体受扰动程度最剧烈,该位置测点最早进入液化状态,其孔隙水压力振荡幅度、相对振荡幅度和超静孔隙水压力比峰值均高于两端土体;沿径向与振动中心距离越近,测点振动加速度、最大超静孔隙水压力比越大,进入液化状态越早,液化持续时间越长。试验结果对注浆时机选择、出浆口位置设置、振动参数选取等具有指导作用,为进一步开展径向振动注浆试验研究奠定了基础。To investigate the disturbance effect of radial vibration excitation on saturated sand,the vibration test system with radial excitation capability and adjustable frequency was developed.Disturbance tests on saturated sand were conducted using this system under vibration frequencies ranging from 10 to 50 Hz.The spatiotemporal evolution and distribution characteristics of the disturbance effect induced by radial vibration excitation were analyzed.The results indicated that,within the scope of the test conditions,the pore water pressure at each measurement point initially increased,and after reaching its peak,gradually decreased and stabilized under vibration excitation.It was observed that as the vibration frequency increased,the degree of disturbance to the saturated sand became more severe,with a gradual increase in excess pore water pressure,excess pore pressure ratio,liquefaction duration,and vibration acceleration at each measurement point.At the vibration frequency of 30 Hz,some measurement points reached liquefaction state,while at 40 Hz and 50 Hz,all measurement points entered liquefaction state.Moreover,as the depth increased,the pore pressure at each measurement point during vibration was higher,the peak was reached earlier,and the liquefaction duration was shorter.The soil near the middle of the vibrator experienced the most severe disturbance,with measurement points in this location entering liquefaction state earliest,and the amplitude of pore pressure oscillation,relative oscillation amplitude,and peak excess pore pressure ratio were all higher at these measurement points compared to those at both ends of the soil.Additionally,the closer the measurement points were to the vibration center along the radial direction,the greater the vibration acceleration,the higher the maximum excess pore pressure ratio,the earlier the entry into liquefaction state,and the longer the duration of liquefaction.These findings provide guidance for selecting grouting timing,setting grouting outlet positions,and choosing vib

关 键 词：土力学 径向振动激励 饱和砂土 试验装置 扰动效应 

分 类 号：TU43[建筑科学—岩土工程]