Shaking table test on liquefaction characteristics of foundation around a complicated subway station with diaphragm walls
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摘要: 地下结构的外部轮廓及其对整体抗侧刚度产生明显改变的附属构筑物都将对主体的抗震性能、变形性态和破坏特征等产生显著影响。通过开展可液化地基土-地下连续墙-异跨地铁车站结构动力相互作用的大型振动台模型试验,对比分析了不同强度地震动作用下模型地基的孔隙水压力发展、加速度响应和地表震陷等动力响应规律。试验结果表明：地连墙和地下结构的存在明显减小了其周围地基的加速度和动孔压比反应,且地基液化程度不同时的影响规律存在明显差异；模型地基对地震动的低频段反应更为强烈,反应谱随地震动强度的增大逐渐向长周期移动；当输入地震动强度较小时,模型结构和场地均出现少许沉降,强地震动作用下的地基土沉陷明显,地下结构呈整体水平上浮状态；模型地基动孔压发展及其分布沿结构纵向变化较小,根据试验结果给出了具体的影响规律及其影响机理。Abstract: The external profile of the underground structures and the annexes which greatly change the lateral stiffness of the whole structures have significant influences on the seismic performance, deformation behavior and failure characteristics of the main structures. Large-scale shaking table model tests on the dynamic interaction system of liquefied site-diaphragm wall-complicated subway station are carried out. The test results of the development of pore water pressure, acceleration of model system, earthquake-induced ground settlement and structure uplifting are compared and analyzed. It is shown that the underground structures and the diaphragm walls have great effects on the earthquake responses of soil foundation around the structures, which are also affected greatly by the liquefaction condition of soil foundation. The model system is more responsive to the low frequency of ground motion, and the acceleration response spectrum moves towards the long period with the increase of the seismic excitation intensity. Although the station and model site suffer from subsidence when subjected to small seismic vibration, the underground structure system appears to rise obviously under the action of strong seismic loading. In addition, the distribution of pore water pressure and its development process of the model foundation are roughly the same along the longitudinal structure. As a result, the effects on the dynamic pore water pressure are also analyzed.
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图 1 异跨地铁车站模型结构横截面尺寸及模型结构体系
Figure 1. Cross-sectional dimensions of unequal-span subway station and preparation of model structure system
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图 4 Taft波加速度时程及傅里叶谱
Figure 4. Acceleration time-histories and Fourier spectra of Taft motion
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图 6 地表震陷与结构上浮位移反应
Figure 6. Vertical displacements of ground surface and subway station
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图 11 模型地基竖直向路径动孔压比反应时程
Figure 11. Responses of dynamic pore pressure ratio of model foundation on vertical path
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图 12 模型地基水平向路径Path-4动孔压比反应时程
Figure 12. Responses of dynamic pore pressure ratio of model foundation on Path-4
表 1 振动台试验体系相似比设计
Table 1 Similarity ratios of shaking table test system
类型 物理量 相似关系 相似比 模型结构 模型地基 几何特征 长度l Sl 1/30 1/4 惯性矩I SI = Sl4 1.23×10-6 — 位移u Su = Sl 1/30 1/4 材料特征 等效密度ρ Sρ = SE/(SaSl) 7.5 1 质量m Sm = SESl2/Sa 2.77×10-4 — 弹性模量E SE 1/4 — 应力σ Sσ = SεSE 1/4 — 应变ε Sε 1 — 剪切波速Vs Sv — 1/2 剪切模量G SG — 1/4 有效覆土压力σz Sσ = SlSgSρ — 1/4 动力特征 输入振动持时t St = (Sl/Sa)1/2 1/5.4794 1 输入振动加速度a Sa 1 1 频率ω Sω = 1/St 5.4794 2 孔隙水压力u Su = SlSaSρ — 1/4 
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表 2 振动台试验加载工况
Table 2 Loading programs of shaking table tests
序号 地震动 输入基岩峰值加速度/g 持时/s 1 白噪声 0.05 60 2 Taft波 0.05 54.4 3 Taft波 0.15 54.4 4 Taft波 0.30 54.4 5 白噪声 0.05 60
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[1] 杜修力, 李洋, 许成顺, 等. 1995年日本阪神地震大开地铁车站震害原因及成灾机理分析研究进展[J]. 岩土工程学报, 2018, 40(2): 223-236. https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC201802003.htm DU Xiu-li, LI Yang, XU Cheng-shun, et al. Review on damage causes and disaster mechanism of Daikai subway station during 1995 Osaka-Kobe Earthquake[J]. Chinese Journal of Geotechnical Engineering, 2018, 40(2): 223-236. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC201802003.htm
[2] 庄海洋, 付继赛, 陈苏, 等. 微倾斜场地中地铁地下结构周围地基液化与变形特性振动台模型试验研究[J]. 岩土力学, 2019, 40(4): 1263-1262. https://www.cnki.com.cn/Article/CJFDTOTAL-YTLX201904004.htm ZHUAGN Haiyang, FU Jisai, CHEN Su, et al. Liquefaction and deformation of the soil foundation around a subway underground structure with a slight inclined ground surface by the shaking table test[J]. Rock and Soil Mechanics, 2019, 40(4): 1263-1262. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTLX201904004.htm
[3] CHEN Z Y, CHEN W, LI Y Y, et al. Shaking table test of a multi-story subway station under pulse-like ground motions[J]. Soil Dynamics and Earthquake Engineering, 2016, 82: 111-122. doi: 10.1016/j.soildyn.2015.12.002
[4] KHERADI H, NAGANO K, NISHI H, et al. 1-g shaking table tests on seismic enhancement of existing box culvert with partial ground-improvement method and its 2D dynamic simulation[J]. Soils and Foundations, 2018, 58(3): 563-581. doi: 10.1016/j.sandf.2018.01.002
[5] YAN X, YUAN J Y, YU H T, et al. Multi-point shaking table test design for long tunnels under non-uniform seismic loading[J]. Tunnelling and Underground Space Technology, 2016, 59: 114-126. doi: 10.1016/j.tust.2016.07.002
[6] 陈国兴, 左熹, 王志华, 等. 可液化场地地铁车站结构地震破坏特性振动台试验研究[J]. 建筑结构学报, 2012, 33(1): 128-137. https://www.cnki.com.cn/Article/CJFDTOTAL-JZJB201201017.htm CHEN Guo-xin, ZUO Xi, WANG Zhi-hua, et al. Shaking table test on seismic failure characteristics of subway station structure at liquefiable ground[J]. Rock and Soil Mechanics, 2012, 33(1): 128-137. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-JZJB201201017.htm
[7] CHIAN S C, TOKIMATSU K, MADABHUSHI S P G. Soil liquefaction-induced uplift of underground structures: physical and numerical modeling[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2014, 140(10): 04014057. doi: 10.1061/(ASCE)GT.1943-5606.0001159
[8] TSINIDIS G, ROVITHIS E, PITILAKIS K, et al. Seismic response of box-type tunnels in soft soil: experimental and numerical investigation[J]. Tunnelling and Underground Space Technology, 2016, 59: 199-214. doi: 10.1016/j.tust.2016.07.008
[9] 许成顺, 李洋, 杜修力, 等. 上覆土竖向惯性力对浅埋地下框架结构地震损伤反应影响离心机振动台模型试验研究[J]. 土木工程学报, 2019, 52(3): 100-119. https://www.cnki.com.cn/Article/CJFDTOTAL-TMGC201903010.htm XU Cheng-shun, LI Yang, DU Xiu-li, et al. Dynamic centrifuge tests for influence of vertical inertia force of overburden soil on earthquake damage response of shallow-buried underground frame structures[J]. China Civil Engineering Journal, 2019, 52(3): 100-119. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-TMGC201903010.htm
[10] ZHAO H L, YUAN Y, YE Z M, et al. Response characteristics of an atrium subway station subjected to bidirectional ground shaking[J]. Soil Dynamics and Earthquake Engineering, 2019, 125: 105737. doi: 10.1016/j.soildyn.2019.105737
[11] TAO L J, DING P, SHI C, et al. Shaking table test on seismic response characteristics of prefabricated subway station structure[J]. Tunnelling and Underground Space Technology, 2019, 91: 102994. doi: 10.1016/j.tust.2019.102994
[12] CHEN S, TANG B Z, ZHAO K, et al. Seismic response of irregular underground structures under adverse soil conditions using shaking table tests[J]. Tunnelling and Underground Space Technology, 2020, 95: 103145. doi: 10.1016/j.tust.2019.103145
[13] 王建宁, 窦远明, 庄海洋, 等. 土-地下连续墙-复杂异跨地铁车站结构动力相互作用分析[J]. 岩土工程学报, 2019, 41(7): 1235-1243. https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC201907009.htm WANG Jian-ning, DOU Yuan-ming, ZHUANG Hai-yang, et al. Seismic responses of dynamic interaction system of soil-diaphragm wall- complicated unequal-span subway station[J]. Chinese Journal of Geotechnical Engineering, 2019, 41(7): 1235-1243. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC201907009.htm
[14] 陈国兴, 王志华, 左熹, 等. 振动台试验叠层剪切型土箱的研制[J]. 岩土工程学报, 2010, 32(1): 89-97. https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC201001017.htm CHEN Guo-xing, WANG Zhi-hua, ZUO Xi, et al. Development of laminar shear soil container for shaking table tests[J]. Chinese Journal of Geotechnical Engineering, 2010, 32(1): 89-97. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC201001017.htm
[15] 许成顺, 豆鹏飞, 高畄成, 等. 地震动持时压缩比对可液化地基地震反应影响的振动台试验[J]. 岩土力学, 2019, 40(1): 147-155. https://www.cnki.com.cn/Article/CJFDTOTAL-YTLX201901012.htm XU Cheng-shun, DOU Peng-fei, GAO Liu-cheng, et al. Shaking table test on effects of ground motion duration compression ratio on seismic response of liquefied foundation[J]. Rock and Soil Mechanics, 2019, 40(1): 147-155. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTLX201901012.htm
[16] YASUDA S, HARADA K, ISHIKAWA, K, et al. Characteristics of liquefaction in Tokyo bay area by the 2011 Great East Japan Earthquake[J]. Soils and Foundations, 2012, 52(5): 793-810.
[17] WANG J N, MA G W, ZHUANG H Y, et al. Influence of diaphragm wall on seismic responses of large unequal-span subway station in liquefiable soils[J]. Tunnelling and Underground Space Technology, 2019, 91: 102988.
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