摘要
为研究砂土地层在动荷载作用下的液化现象及地铁地下结构对动力的响应特性,以西安地铁1号线某区段为例,建立了砂土地层地铁地下结构模型并进行振动台试验。研究发现:在动力荷载下,砂层具有加速度放大效应,且峰值加速度随土层埋深的增大而减小,傅里叶主频级数均出现在1~2 Hz处;动荷载下砂土液化,砂土振动最大加速度随埋深不断衰减,孔隙水压力随时间推移先上升后趋于平稳;砂土地层中地铁地下结构在动荷载作用下出现上浮现象,孔隙水在中心处聚集并突涌,具有较大的工程危害。
In order to study the liquefaction phenomenon of sand stratum under dynamic load and the response characteristics of underground metro structure to dynamic force,a section of Xi'an metro line 1 was taken as an example to establish the underground structure model of subway in sandy soil stratum and conduct the shaking table test.The research found that:under dynamic load,the sand layer has an acceleration amplification effect,and the peak acceleration decreases with the increase of buried depth of the soil layer,and the Fourier series of main frequencies occur at 1~2 Hz;under the dynamic load,the sand liquefies,the maximum vibration acceleration of the sand decreases with the buried depth,and the pore water pressure first rises and then tends to be stable with increasing time;the underground subway structure in the sandy soil stratum appears to rise under the action of dynamic load,and the pore water accumulates and surges in the center,which has great engineering hazards.
作者
赵立刚
ZHAO Ligang(China Railway 18th Bureau Group Municipal Engineering Co.,Ltd.,Tianjin 300222,China)
出处
《建筑施工》
2019年第10期1930-1932,共3页
Building Construction
关键词
砂土地层
地铁地下工程
土体液化
动力响应特性
sandy soil stratum
underground metro project
soil liquefaction
dynamic response characteristics
