饱和砂土地基液化离心机振动台模型试验研究
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摘要
通过开展饱和砂土地基水平振动的离心机振动台试验,研究了振动液化过程中砂土地基的动力响应沿深度的变化规律,发现在液化过程中,由于剪切模量的变化,液化土层与下部未液化土层之间将形成反射界面,后续传来地震波所携带的能量将通过该界面反射至下部土层,导致其动力响应显著变大;同时发现土层在经历液化过程后,其抗液化能力会显著提高,但再次地震时,发生过液化的土层的动力响应也将明显增大。研究结果能够加深对于饱和砂土地基中地震动传播规律的认识,同时也可为验证和改进现有评估砂土液化影响的计算方法提供试验数据。
Dynamic centrifuge tests were performed on a uniform saturated sand foundation bed model;dynamic responses of different soil layers with various depths were analyzed. It is found that in the course of sand liquefaction,due to the variation of the shear modules in the liquefaction layer,a reflection interface will form between the liquefaction layer and its neighborhood sand layer,which will reflect energy carried by the subsequent shake wave to the sand layer right below the liquefaction layer,and finally make the dynamic response of the mentioned beneath layer get a notable increase;meanwhile,as for those sand layers that have experienced liquefaction,their liquefaction resistance would get notable improved,but those postliquefaction sand layer will demonstrate greater dynamic response during subsequent earthquakes. The research work will improve our understanding on the propagation law of the shake wave in the saturated sand foundation bed model,and the test data can be used to verify and improve the numerical method for evaluating the influence of liquefaction on a saturated sand foundation.
Dynamic centrifuge tests were performed on a uniform saturated sand foundation bed model;dynamic responses of different soil layers with various depths were analyzed. It is found that in the course of sand liquefaction,due to the variation of the shear modules in the liquefaction layer,a reflection interface will form between the liquefaction layer and its neighborhood sand layer,which will reflect energy carried by the subsequent shake wave to the sand layer right below the liquefaction layer,and finally make the dynamic response of the mentioned beneath layer get a notable increase;meanwhile,as for those sand layers that have experienced liquefaction,their liquefaction resistance would get notable improved,but those postliquefaction sand layer will demonstrate greater dynamic response during subsequent earthquakes. The research work will improve our understanding on the propagation law of the shake wave in the saturated sand foundation bed model,and the test data can be used to verify and improve the numerical method for evaluating the influence of liquefaction on a saturated sand foundation.
引文
[1]Finn W D L.Liquefaction potential:developments since 1976[C]//Proc.International Conference on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics.St Louis,Missouri,1981:655-681.
[2]谢定义.饱和砂土液化的若干问题[J].岩土工程学报,1992,14(3):90-98.
[3]赵成刚.饱和砂土液化与稳态强度[J].土木工程学报,2001,34(3):90-96.
[4]National Research Council.Liquefaction during earthquakes,committe on earthquake engineering[M].Washington D.C:National Academy Press,1985.
[5]陈国兴,胡庆兴,刘雪珠.关于砂土液化判别的若干意见[J].地震工程与工程振动,2002,22(1):141-151.
[6]张建民,王建华.土动力学与土工抗震[C]//第八届土力学及岩土工程学术会议论文集,北京:万国学术出版社,1999:573-576.
[7]Adalier K,Elgamal A.Liquefaction of over-consolidated sand:a centrifuge investigation[J].Journal of Earthquake Engineering,2005,9(1):127-150.
[8]苏栋,李相崧.饱和砂土场地在小震下的响应(英文)[J].深圳大学学报:理工版,2007,24(4):339-343.
[9]章为民,日下部治.砂性地层地震反应离心模型试验研究[J].岩土工程学报,2001,23(1):28-31.
[10]Hushmand B,Scott R F,Crouse.Centrifuge liquefaction tests in a laminar box[J].Geotechnique.1988,38(2):253-262.
[11]苏栋,李相崧.可液化土中单桩地震响应的离心机试验研究[J].岩土工程学报,2006,28(4):423-427.
[12]于玉贞,李荣建,李广信,等.饱和砂土地基上边坡地震动力离心模型试验研究[J].清华大学学报:自然科学版,2008,48(9):1422-1425.
[13]汪兵业,封渊惟,陈小亮.地下结构物对饱和砂土地基液化的影响[J].佳木斯大学学报:自然科学版,2012,30(4):528-531.
[14]周燕国,梁甜,李永刚,等.含黏粒砂土场地液化离心机振动台试验研究[J].岩土工程学报,2013,35(9):1651-1658.
[15]李京爽,侯瑜京,徐泽平,等.砂土自由场地基水平垂直振动离心模拟试验[J].岩土力学,2011,32(增刊2):208-214.
[16]刘晶波,刘祥庆,王宗纲,等.砂土地基自由场离心机振动台模型试验[J].清华大学学报,2009,49(9):31-34.
[2]谢定义.饱和砂土液化的若干问题[J].岩土工程学报,1992,14(3):90-98.
[3]赵成刚.饱和砂土液化与稳态强度[J].土木工程学报,2001,34(3):90-96.
[4]National Research Council.Liquefaction during earthquakes,committe on earthquake engineering[M].Washington D.C:National Academy Press,1985.
[5]陈国兴,胡庆兴,刘雪珠.关于砂土液化判别的若干意见[J].地震工程与工程振动,2002,22(1):141-151.
[6]张建民,王建华.土动力学与土工抗震[C]//第八届土力学及岩土工程学术会议论文集,北京:万国学术出版社,1999:573-576.
[7]Adalier K,Elgamal A.Liquefaction of over-consolidated sand:a centrifuge investigation[J].Journal of Earthquake Engineering,2005,9(1):127-150.
[8]苏栋,李相崧.饱和砂土场地在小震下的响应(英文)[J].深圳大学学报:理工版,2007,24(4):339-343.
[9]章为民,日下部治.砂性地层地震反应离心模型试验研究[J].岩土工程学报,2001,23(1):28-31.
[10]Hushmand B,Scott R F,Crouse.Centrifuge liquefaction tests in a laminar box[J].Geotechnique.1988,38(2):253-262.
[11]苏栋,李相崧.可液化土中单桩地震响应的离心机试验研究[J].岩土工程学报,2006,28(4):423-427.
[12]于玉贞,李荣建,李广信,等.饱和砂土地基上边坡地震动力离心模型试验研究[J].清华大学学报:自然科学版,2008,48(9):1422-1425.
[13]汪兵业,封渊惟,陈小亮.地下结构物对饱和砂土地基液化的影响[J].佳木斯大学学报:自然科学版,2012,30(4):528-531.
[14]周燕国,梁甜,李永刚,等.含黏粒砂土场地液化离心机振动台试验研究[J].岩土工程学报,2013,35(9):1651-1658.
[15]李京爽,侯瑜京,徐泽平,等.砂土自由场地基水平垂直振动离心模拟试验[J].岩土力学,2011,32(增刊2):208-214.
[16]刘晶波,刘祥庆,王宗纲,等.砂土地基自由场离心机振动台模型试验[J].清华大学学报,2009,49(9):31-34.
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