防水措施对堤坝地震液化影响的数值分析
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摘要
通过基于有效应力的完全耦合动力分析方法,研究了混凝土面板坝在地震作用下的动力响应,详细地讨论了堤坝迎水面斜坡上铺设的防水毯对堤坝地震液化的影响。计算中土体采用Cyclic mobility本构模型,该模型通过在修正剑桥模型上增加应力诱导各向异性、超固结和结构性的概念及其相关发展准则,可以很好地描述可液化土体的动力特性。计算结果表明防水毯的存在可以有效降低坝体的地下水位浸润线,增加坝基的初始有效应力,从而降低坝基地震液化发生的可能性,同时坝体的变形明显减小。
The earthquake induced liquefaction of embankment is analyzed using the effective-stress based fully coupled dynamic analysis method.Special emphasis is given to discuss the effect of waterproof carpet paved on the slope of the upstream.The behaviors of the foundation soils are described by means of a cyclic mobility constitutive model which was developed at the bases of modified Cam model by introducing concepts such as stress-induced anisotropy,over-consolidation,and structure.Results show that the phreatic line become lower due to the effect of the waterproof carpet,which increases the initial effective stress of dam foundation and reduces the possibility of liquefaction.Furthermore,the deformation is reduced effectively.
The earthquake induced liquefaction of embankment is analyzed using the effective-stress based fully coupled dynamic analysis method.Special emphasis is given to discuss the effect of waterproof carpet paved on the slope of the upstream.The behaviors of the foundation soils are described by means of a cyclic mobility constitutive model which was developed at the bases of modified Cam model by introducing concepts such as stress-induced anisotropy,over-consolidation,and structure.Results show that the phreatic line become lower due to the effect of the waterproof carpet,which increases the initial effective stress of dam foundation and reduces the possibility of liquefaction.Furthermore,the deformation is reduced effectively.
引文
[1]SEED H B,MAKDISI F I,IDISS I M,et al.The slides inthe San Fernando Dams during the earthquake ofFebruary 9,1971[J].Journal of the GeotechnicalEngineering Division,(ASCE),1975,101(7):651-688.
[2]MING H Y,LI X S.Fully coupled analysis of failure andremediation of Lower San Fernando Dam[J].Journal ofgeotechnical and geoenvironmental engineering,2003,129(4):336-349.
[3]SHARP MK,ADALIER K.Seismic response of earthdam with varying depth of liquefiable foundation layer[J].Soil Dynamics and Earthquake Engineering,2006,126:1028-1037.
[4]SICA S,PAGANO L,MODARESSI A.Influence of pastloading history on the seismic response of earth dams[J].Computers and Geotechnics,2007,35:61-85.
[5]徐长节,蔡袁强.杭州钱塘江防洪堤抗震分析[J].岩土力学,2006,27(1):67-72.XU Chang-jie,CAI Yuan-qiang.Aseismic analysis offlood protection levee of Qiangtang River in Hangzhouarea[J].Rock and Soil Mechanics,2006,27(1):67-72.
[6]ASAOKA A,NODA T,YAMADA E,et al.An elasto-plasticdescription of two distinct volume change mechanisms ofsoils[J].Soils and Foundations,2002,42(5):47-57.
[7]ZHANG F,YE B,NODA T,et al.Explanation of cyclicmobility of soils:approach by stress-induced anisotropy[J].Soils and Foundations,2007,47(4):635-648.
[8]YE B,YE G L,ZHANG F,et al.Experiment andnumerical simulation of repeated liquefaction-consolidationof sand[J].Soils and Foundations,2007,47(3):547-558.
[9]张锋.计算土力学[M].北京:人民交通出版社,2007.
[2]MING H Y,LI X S.Fully coupled analysis of failure andremediation of Lower San Fernando Dam[J].Journal ofgeotechnical and geoenvironmental engineering,2003,129(4):336-349.
[3]SHARP MK,ADALIER K.Seismic response of earthdam with varying depth of liquefiable foundation layer[J].Soil Dynamics and Earthquake Engineering,2006,126:1028-1037.
[4]SICA S,PAGANO L,MODARESSI A.Influence of pastloading history on the seismic response of earth dams[J].Computers and Geotechnics,2007,35:61-85.
[5]徐长节,蔡袁强.杭州钱塘江防洪堤抗震分析[J].岩土力学,2006,27(1):67-72.XU Chang-jie,CAI Yuan-qiang.Aseismic analysis offlood protection levee of Qiangtang River in Hangzhouarea[J].Rock and Soil Mechanics,2006,27(1):67-72.
[6]ASAOKA A,NODA T,YAMADA E,et al.An elasto-plasticdescription of two distinct volume change mechanisms ofsoils[J].Soils and Foundations,2002,42(5):47-57.
[7]ZHANG F,YE B,NODA T,et al.Explanation of cyclicmobility of soils:approach by stress-induced anisotropy[J].Soils and Foundations,2007,47(4):635-648.
[8]YE B,YE G L,ZHANG F,et al.Experiment andnumerical simulation of repeated liquefaction-consolidationof sand[J].Soils and Foundations,2007,47(3):547-558.
[9]张锋.计算土力学[M].北京:人民交通出版社,2007.
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