平原水库土石坝饱和砂土地基地震液化分析
|
摘要
本文运用FLAC3D有限差分软件对某水库大坝地基可液化土层在不同库水位作用下的液化特性进行动力反应分析,探讨了饱和砂土地基在地震作用下的孔隙水压力变化过程以及土石坝各典型节点的加速度和位移响应.结果表明:在设防烈度为Ⅶ度的情况下,距离坝体较远的可液化土层易发生液化,库水位处于高水位时上游坝脚附近的可液化土体发生液化的可能性较低水位时小,但下游坝脚处可液化土层发生液化的可能性较低水位高,坝体下方可液化土体最难液化.坝顶的加速度峰值放大倍数最大,坝基液化土体过滤了地震波的高频成分,减缓了地面节点的加速度.坝体周围出现了不同程度的隆起现象,坝体整体的水平位移大于竖向位移.
FLAC3 Dis used to analyze the characteristics of liquefaction of saturated sandy soil foundation in a reservoir dam foundation with liquefaction soil under different water levels.How the pore water pressure changes under seismic loading is discussed and the displacement responses of earth-rock dam in various typical nodes are analyzed.The results show that under the condition of the fortification intensity of seven degrees,the liquefaction soil approaching the toe of the dam in a low upstream water level is more likely to liquefy than it is in a high water level;but the liquefaction soil approaching the foot of the dam in a low water level is less likely to liquefy than it is in a high water level.The liquefaction soil beneath the body of the dam is the most difficult to liquefy.The horizontal displacement of the dam body is greater than that of vertical displacement.
FLAC3 Dis used to analyze the characteristics of liquefaction of saturated sandy soil foundation in a reservoir dam foundation with liquefaction soil under different water levels.How the pore water pressure changes under seismic loading is discussed and the displacement responses of earth-rock dam in various typical nodes are analyzed.The results show that under the condition of the fortification intensity of seven degrees,the liquefaction soil approaching the toe of the dam in a low upstream water level is more likely to liquefy than it is in a high water level;but the liquefaction soil approaching the foot of the dam in a low water level is less likely to liquefy than it is in a high water level.The liquefaction soil beneath the body of the dam is the most difficult to liquefy.The horizontal displacement of the dam body is greater than that of vertical displacement.
引文
[1]李红军.高土石坝地震变形分析与抗震安全评价[D].大连:大连理工大学,2008.
[2]邓益兵,周健,刘文白,等.水库围堤地基液化有效应力动力分析[J].岩土力学,2010,32(s2):292-296.
[3]李飒,刘松良,要明伦,等.地震作用下渗流对平原水库土石坝稳定的影响[J].岩石力学与工程学报,2008,27(4):858-864.
[4]严祖文,李敬梅.水库大坝地基地震液化特性及动力有限元分析[J].水力发电学报,2006,25(6):45-49.
[5]陈育民,仉文岗,刘汉龙.堤防地震液化数值模拟及动力反应分析[J].解放军理工大学(自然科学版),2011,12(3):239-244.
[6]钱家欢,殷宗泽.土工原理与计算[M].北京:中国水利水电出版社,1996.
[7]陈育民.FLAC/FLAC3D基础与工程实例[M].北京:中国水利水电出版社,2008.
[8]顾宝和,石兆吉.地震液化效应的综合评价[J].工程地质学报,1995,3(3):1-10.
[9]韩石,贡金鑫,张艳青.地震作用下重力式码头地基液化及变形[J].水利水运工程学报,2013,35(4):45-54.
[10]李培振,任红梅,吕西林,等.液化地基自由场振动台模型试验研究[J].地震工程与工程振动,2008,28(2):171-178.
[2]邓益兵,周健,刘文白,等.水库围堤地基液化有效应力动力分析[J].岩土力学,2010,32(s2):292-296.
[3]李飒,刘松良,要明伦,等.地震作用下渗流对平原水库土石坝稳定的影响[J].岩石力学与工程学报,2008,27(4):858-864.
[4]严祖文,李敬梅.水库大坝地基地震液化特性及动力有限元分析[J].水力发电学报,2006,25(6):45-49.
[5]陈育民,仉文岗,刘汉龙.堤防地震液化数值模拟及动力反应分析[J].解放军理工大学(自然科学版),2011,12(3):239-244.
[6]钱家欢,殷宗泽.土工原理与计算[M].北京:中国水利水电出版社,1996.
[7]陈育民.FLAC/FLAC3D基础与工程实例[M].北京:中国水利水电出版社,2008.
[8]顾宝和,石兆吉.地震液化效应的综合评价[J].工程地质学报,1995,3(3):1-10.
[9]韩石,贡金鑫,张艳青.地震作用下重力式码头地基液化及变形[J].水利水运工程学报,2013,35(4):45-54.
[10]李培振,任红梅,吕西林,等.液化地基自由场振动台模型试验研究[J].地震工程与工程振动,2008,28(2):171-178.