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研究目的:本文以佛山地铁2号线盾构区间工程为依托,现场取样砂土,通过动三轴试验获取原状土体和加固土体计算参数,运用有限元分析软件ANSYS进行计算分析,对可液化砂土地层盾构隧道在横向地震波激励下的动力响应和地层加固减震效果进行量化研究与评价.研究结论:(1)在横向地震荷载作用下,地层与结构的地震响应峰值与地震波峰值在时间上并不同步,且地层与结构的地震响应发展规律差异亦较大,衬砌第一主应力最大值1.69 MPa;(2)隧道周围地层采取加固措施后,地层强度参数越大,管片位移降幅越大,主应力增(减)幅越大,可满足隧道强度和运营要求;(3)考虑到盾构掘进过程对邻近建筑物的影响,建议砂土地层地基加固采用每立方米掺入400 kg超细水泥的加固方案;(4)本研究结果可应用于可液化砂土地层盾构隧道抗震设计和选取加固措施.“,”Research purposes:In this paper,taking Foshan Metro Line 2 shield project as an example,the undisturbed soil and calculation parameters of soil reinforcement are obtained through field sampling of sand and dynamic triaxial test,which are calculated and analyzed using finite element analysis software ANSYS,the dynamic response and the formation of liquefiable sand soil layer are quantified and evaluated in shield tunnel under horizontal seismic wave excitation the damping effect of reinforcement.Research conclusions:(1) In the transverse seismic loading,strata and structural seismic response and seismic wave peak value is not synchronized in time,and the formation and development of the seismic response of the structure are different,the first principal stress maximum value of the lining is 1.69 MPa.(2) After taking the reinforcement measures of tunnel surrounding strata,the greater the stratum strength parameters is,the greater the decline of segment displacement is,and the greater the amplitude of principal stress increase (decrease) is,which can meet the operational requirements and strength of tunnel.(3) Considering the influence of shield tunneling process on adjacent buildings,it is suggested that the reinforcement of sand soil layer be reinforced with 400 kg superfine cement per cubic meter.(4) The research results can be applied to the seismic design and selection of reinforcement measures for the shield tunnel in liquefiable sand soil.