地震液化对地铁地下结构影响的振动台试验研究
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摘要
研究目的:当地下结构位于地震液化地层中时,地震液化引起地下结构内力重分布,相关的实测数据罕见且不易搜集。以往相关研究主要依靠理论分析和数值模拟方式对地下结构的响应进行探讨,并不能真实地重现地震液化过程地层与结构的变化。为取得第一手数据,通过在振动台上建立相似比模型,并以不同的地震波作为地震液化的输入条件,对地震液化过程中的试验数据进行归纳总结,得出相应规律。研究结论:(1)地震液化地层中的地铁车站结构,在长度方向中部受到的液化土压力值最大;(2)横向土压力与振动台最大加速度成正比关系;(3)车站结构顶部、底部和周围地层的孔隙水压力,随着振动作用累积上升而最终趋于稳定;(4)地铁车站围护结构的围封具有一定的抗液化作用;(5)本研究成果可为地震液化地层中地铁地下结构的抗液化措施提供参考。
Research purposes: When the underground structure is located in the seismic liquefaction stratum,the internal force redistribution of the underground structure is caused by the seismic liquefaction. Relevant measured data are rare and difficult to collect. In the past,the response of underground structures was mainly studied by theoretical analysis and numerical simulation,which could not really reproduce the changes of stratum and structure in the process of seismic liquefaction. In order to obtain first-hand data,a similarity ratio model was established on the shaking table,and different seismic waves were used as input conditions for seismic liquefaction. The monitoring data in the process of seismic liquefaction are analyzed and sorted out,and the corresponding laws are obtained.Research conclusions:( 1) Earthquake liquefaction earth pressure on the middle of the station structure is the largest,and it is most vulnerable to breakage during earthquake.( 2) The lateral dynamic earth pressure is proportional to the peak acceleration of the shaking table.( 3) Pore water pressure is generated in the top,bottom and underlying strata of underground structures,and finally tends to be stable with the cumulative increase of vibration.( 4) The underground structure enclosed by the enclosure structure of subway station has a certain anti-liquefaction effect.( 5) The research results can provide design reference for underground structure of subway in seismic liquefaction stratum.
Research purposes: When the underground structure is located in the seismic liquefaction stratum,the internal force redistribution of the underground structure is caused by the seismic liquefaction. Relevant measured data are rare and difficult to collect. In the past,the response of underground structures was mainly studied by theoretical analysis and numerical simulation,which could not really reproduce the changes of stratum and structure in the process of seismic liquefaction. In order to obtain first-hand data,a similarity ratio model was established on the shaking table,and different seismic waves were used as input conditions for seismic liquefaction. The monitoring data in the process of seismic liquefaction are analyzed and sorted out,and the corresponding laws are obtained.Research conclusions:( 1) Earthquake liquefaction earth pressure on the middle of the station structure is the largest,and it is most vulnerable to breakage during earthquake.( 2) The lateral dynamic earth pressure is proportional to the peak acceleration of the shaking table.( 3) Pore water pressure is generated in the top,bottom and underlying strata of underground structures,and finally tends to be stable with the cumulative increase of vibration.( 4) The underground structure enclosed by the enclosure structure of subway station has a certain anti-liquefaction effect.( 5) The research results can provide design reference for underground structure of subway in seismic liquefaction stratum.
引文
[1]宫全美,周顺华,张婉琴,等.盾构隧道易液化地基的抗液化措施研究[J].上海铁道大学学报,2000(10):110-114.Gong Quanmei,Zhou Shunhua,Zhang Wanqin,etc.Anti-liquefaction Measure Research of Liquefied Layers of Shield Tunneling[J]. Journal of Shanghai Tiedao University,2000(10):110-114.
[2]钟小春,刘汉龙,余湘娟,等.修建地铁隧道后场地液化特征的判别[J].岩土力学,2003(4):266-272.Zhong Xiaochun, Liu Hanlong, Yu Xiangjuan,etc.Distinguishing Liquefaction Characteristics of Foundations around Subway Tunnel[J]. Rock and Soil Mechanics,2003(4):266-272.
[3]黄昌富,迟大祥,田书广,等.地铁线路穿越急倾斜煤层采空塌陷区相似模型试验[J].科学技术与工程,2018(11):58-62.Huang Changfu,Chi Daxiang,Tian Shuguang,etc.Similarity Model Test of Subway Line Passing Steeply Inclined Mined-out Subsidence Area[J]. Science Technology and Engineering,2018(11):58-62.
[4]商厚胜,岳丰田,石荣剑.浅覆土下矩形冻结加固的模型试验研究[J].岩土力学,2014(10):149-155.Shang Housheng,Yue Fengtian,Shi Rongjian. Model Test of Artificial Ground Freezing in Shallow-buried Rectangular Cemented Soil[J]. Rock and Soil Mechanics,2014(10):149-155.
[5] Siriwardane,Desai C S. Computational Procedures for Non-linear Three-dimensional Analysis with Some Advanced Constitutive Laws[J]. Int. J. Num.Analysis Method in Geomech. 1983(7):143-171.
[6]段亚刚.大范围地震液化条件下地下结构设计研究[J].铁道工程学报,2014(10):49-53.Duan Yagang. Research on the Design of Underground Structure in Large Range of Sand Seismic Liquefaction Conditions[J]. Journal of Railway Engineering Society,2014(10):49-53.
[2]钟小春,刘汉龙,余湘娟,等.修建地铁隧道后场地液化特征的判别[J].岩土力学,2003(4):266-272.Zhong Xiaochun, Liu Hanlong, Yu Xiangjuan,etc.Distinguishing Liquefaction Characteristics of Foundations around Subway Tunnel[J]. Rock and Soil Mechanics,2003(4):266-272.
[3]黄昌富,迟大祥,田书广,等.地铁线路穿越急倾斜煤层采空塌陷区相似模型试验[J].科学技术与工程,2018(11):58-62.Huang Changfu,Chi Daxiang,Tian Shuguang,etc.Similarity Model Test of Subway Line Passing Steeply Inclined Mined-out Subsidence Area[J]. Science Technology and Engineering,2018(11):58-62.
[4]商厚胜,岳丰田,石荣剑.浅覆土下矩形冻结加固的模型试验研究[J].岩土力学,2014(10):149-155.Shang Housheng,Yue Fengtian,Shi Rongjian. Model Test of Artificial Ground Freezing in Shallow-buried Rectangular Cemented Soil[J]. Rock and Soil Mechanics,2014(10):149-155.
[5] Siriwardane,Desai C S. Computational Procedures for Non-linear Three-dimensional Analysis with Some Advanced Constitutive Laws[J]. Int. J. Num.Analysis Method in Geomech. 1983(7):143-171.
[6]段亚刚.大范围地震液化条件下地下结构设计研究[J].铁道工程学报,2014(10):49-53.Duan Yagang. Research on the Design of Underground Structure in Large Range of Sand Seismic Liquefaction Conditions[J]. Journal of Railway Engineering Society,2014(10):49-53.