T he characteristics of the surrounding soil vibration induced by trains running on the Shanghai‐Nan‐jing intercity high‐speed railway(SNHSR) ,the ground vibration attenuation law and the vibration impact on the foundation settlement of Beijing‐Shanghai railway(BSR) ,are studied in this paper .Through the establishment of the numerical analysis model ,the influence of pile‐geogrid structure composite foundation and soil conditions on the ground vibration is analyzed ,and the cumulative deformation of BSR foundation soil is predicted .The conclusions are as follows :the composite foundation of pile‐geogrid structure can reduce the ground vibration , and the closer to the foundation reinforcement area the more obvious the vibration damping effects are .Ten me‐ters away from the center line of railway ,the ground vibration acceleration peak value declines about 33.8% . The influence of foundation soil characteristics on vibration attenuation is obvious .As the vibration attenuation is fast and the near field ground vibration is intense under soft soil condition ,the influence of vibration on oper‐ating safety of train should be addressed .While under hard soil condition ,the vibration attenuation is slow ,the impact of vibration on ambient environment should be focused on .The vibration attenuation is extremely slow when the surface and underlying soil of the foundation is hard and when there are soft soil layers sandwiched in‐between ,therefore ,attention should be paid to the vibration influence scope under this condition .When the dis‐tance between the slope toes of BSR and SNHSR is 20 m ,cumulative plastic deformation of BSR foundation soil ,induced by the operating vibration of SNHSR ,increases about 3.44% and 7.07% respectively under the current track irregularity and deteriorating track irregularity condition of SNHSR .However ,when the distance between the slope toes of the two railway lines is 5 m ,cumulative plastic deformation of BSR foundation soil in‐duced by the operating vibration of SNHSR increases about 18.36% under the current track irregularity condi‐tion ,which indicates little influence imposed by the track regularity and the distance between the railway lines on the cumulative plastic deformation of foundation soil under the action of cyclic train loads .%本文对沪宁城际高速铁路列车运行引起的周围环境振动特性和振动传播规律，以及振动对京沪铁路地基沉降的影响进行研究。通过建立数值模型，分析桩网结构地基加固方式和土质条件对振动的影响，并对振动引起的京沪铁路地基土体累积变形进行了预测。结果表明：采用桩网结构进行地基加固后，地面振动减弱，且距离地基加固区越近，减振效果越明显，距线路中心线10 m处地面振动加速度峰值下降约33.8％；土质条件对振动传播有较明显的影响，软土条件下，振动衰减较快，近场地面处的振动较大，应重点关注振动对行车安全的影响；较硬土质条件下，振动衰减较慢，应重点关注振动对周围环境的影响；当地基表层和底层土体硬度较大，且中间夹有软土层时，振动衰减速度缓慢，应注意振动的影响范围。两线路基坡脚间距为20 m时，在沪宁城际铁路当前轨道平顺性和平顺性恶化条件下，列车运行导致京沪铁路地基土体累积变形量分别增加3.44％和7.07％；坡脚间距为5 m时，列车运行导致京沪铁路地基土体累积变形量增加18.36％，这反映出轨道平顺性和线间距（沪宁城际与京沪铁路间距离）对列车荷载循环作用下的地基土体累积变形影响较小。
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