边坡主震响应方向性及余震效应的离心模型试验

李超; 管龙华; 何健健; 汪玉冰

doi:10.11779/CJGE20220328

边坡主震响应方向性及余震效应的离心模型试验 English Version

李超^{1, 2,},
管龙华^{1, 2},
何健健^{1, 2},
汪玉冰^{1, 2, ,}

1.
浙江大学超重力研究中心, 浙江杭州 310058
2.
浙江大学软弱土与环境土工教育部重点实验室, 浙江杭州 310058

基金项目:

国家自然科学基金青年科学基金项目 51808490

详细信息

作者简介:
李超(1992—)，男，博士研究生，主要从事地震边坡稳定分析与物理模拟等方面的研究。E-mail: zjuchaoli@zju.edu.cn

通讯作者:
汪玉冰, E-mail: wangyubing@zju.edu.cn

中图分类号: TU411
计量
- 文章访问数: 307
- HTML全文浏览量: 42
- PDF下载量: 75
出版历程
- 收稿日期: 2022-03-22
- 网络出版日期: 2023-02-19
- 刊出日期: 2023-05-31

Centrifugal model tests on mainshock response directionality and aftershock effect of slopes

LI Chao^{1, 2,},
GUAN Longhua^{1, 2},
HE Jianjian^{1, 2},
WANG Yubing^{1, 2, ,}

1.
Center for Hypergravity Experiment and Interdisciplinary Research, Zhejiang University, Hangzhou 310058, China
2.
MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering, Zhejiang University, Hangzhou 310058, China

摘要

摘要: 对含倾斜基岩面的砂土边坡开展50倍重力的离心模型振动台试验，探究主余震序列作用下边坡响应与变形的变化特征。首先通过响应的时程分析和谱分析讨论主震边坡加速度的放大效应，接着借助刚性楔形滑体模型解释主震响应方向性与放大系数的关系和截断效应产生的机理，最后通过累积变形探讨余震效应及其影响状况。研究表明，放大效应是一个与频率有关的量，随着高程的增加低频部分得到了不同程度的放大。而按照PGA定义的放大系数需要结合考虑边坡顺-逆坡向不同所导致的响应方向性问题，截断效应及其与响应方向性的关系则体现了边坡变形与响应的耦合作用。余震效应的分析指出某些部位因余震导致的总位移增量可以与主震引起的变形量相当，在工程设计中应当考虑余震的附加影响。
- 主余震序列 /
- 离心模型试验 /
- 砂土边坡 /
- 放大效应 /
- 截断效应
Abstract: A centrifugal model shaking table test with gravity of 50 times is carried out on a sandy slope containing an inclined bedrock interface to investigate the characteristics of changes in slope response and deformation under the action of the main shock-aftershock sequence. Firstly, the acceleration amplification effect of the mainshock is discussed through the time and spectral analysis, then the relationship between the mainshock response directionality and the amplification coefficient together with the mechanism of the truncation effect is explained using a model for rigid wedge-shaped sliding body. Finally, the aftershock effect and its influence are explored through the cumulative deformation. The results show that the amplification effect is frequency-dependent. The low-frequency part of the response is amplified to different degrees with the increase of elevation, while the amplification coefficient defined by PGA needs to be combined with the consideration of the response directionality due to the difference between downslope and upslope. The truncation effect and its relations with the response directionality reflect the coupling effect of deformation and response of the slope. The analysis of the aftershock effect points out that the total displacement increment of certain parts caused by aftershock can be comparable to that caused by the mainshock. This additional influence of aftershocks should be considered in engineering design.
- mainshock-aftershock sequence /
- centrifugal model test /
- sandy slope /
- amplification effect /
- truncation effect

HTML全文

图 1 模型试验设计图

Figure 1. Design of model tests

下载: 全尺寸图片幻灯片

图 2 离心模型

Figure 2. Centrifuge model

下载: 全尺寸图片幻灯片

图 3 台面输入

Figure 3. Input of shaking table

下载: 全尺寸图片幻灯片

图 4 主震边坡响应

Figure 4. Slope responses under mainshock

下载: 全尺寸图片幻灯片

图 5 响应放大系数

Figure 5. Amplification coefficients of response

下载: 全尺寸图片幻灯片

图 6 局部响应时程

Figure 6. Time histories of partial response

下载: 全尺寸图片幻灯片

图 7 刚性楔形滑体模型

Figure 7. Model for rigid wedge-shaped sliding body

下载: 全尺寸图片幻灯片

图 8 强余震作用下的边坡响应时程

Figure 8. Time histories of response after a strong aftershock

下载: 全尺寸图片幻灯片

图 9 傅里叶谱比变化曲线

Figure 9. Variation of Fourier spectrum ratios

下载: 全尺寸图片幻灯片

图 10 竖向位移变化曲线

Figure 10. Variation of vertical displacements

下载: 全尺寸图片幻灯片

表 1 材料基本性质

Table 1 Properties of materials

类别	黏聚力/kPa	内摩擦角/(°)	最大孔隙比	最小孔隙比	相对质量密度
石英砂	—	37.8	0.878	0.550	2.64
混合土	0.74	35.9	0.877	0.451	2.60

下载: 导出CSV

表 2 传感器布置

类别	高程h/mm	高程比(h/H)	传感器标记
模型箱底部	0	0	A0
基岩部分	80	0.2	A1
基岩部分	300	0.76	A2
地基部分	145	0.37	A3、A4
边坡部分	215	0.55	A5
	295	0.75	A6
	365	0.92	A7

下载: 导出CSV

表 3 施振方案

Table 3 Arrangement of sensors Table 3 Vibration schemes

项目	主震	强余震	弱余震
类型	脉冲型	脉冲型	无脉冲
PGA (g)	0.55	0.36	0.18
注：无脉冲型和脉冲型区别及差异性论述具体可参照近断层地震的向前方向性和滑冲效应^[20]

下载: 导出CSV

表 4 模型边坡竖向位移

Table 4 Vertical displacements of model slope

类别	S1/mm	S2/mm	S3/mm	S4/mm
初始	0	0	0	0
主震	-128.885	-43.23	114.95	38.57
强余震	-163.08	-67.975	128.37	56.26
弱余震	-180.31	-74.831	130.38	89.25
余震占比	28.5%	42.2%	11.8%	56.8%
注：1.表中负值代表隆起，正值代表竖向下沉。2.以上的值均是离心机加速稳定以后仅由地震荷载导致。

下载: 导出CSV

参考文献(23)

[1]	CLOUGH R W, PIRTZ D. Earthquake resistance of rock-fill dams[J]. Transactions of the American Society of Civil Engineers, 1958, 123(1): 792-810. doi: 10.1061/TACEAT.0007548
[2]	KUTTER B L. Recent advances in centrifuge modeling of seismic shaking[C]// 3rd International Conference on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics. St Louis, 1995.
[3]	MADABHUSHI S P G, HAIGH S K, SUBEDI B R. Seismic behaviour of steep slopes[M]// Physical Modelling in Geotechnics. London: Routledge, 2022: 489-494.
[4]	YU Y Z, DENG L J, SUN X, et al. Centrifuge modeling of a dry sandy slope response to earthquake loading[J]. Bulletin of Earthquake Engineering, 2008, 6(3): 447-461. doi: 10.1007/s10518-008-9070-9
[5]	BRENNAN A J, MADABHUSHI S P G. Amplification of seismic accelerations at slope crests[J]. Canadian Geotechnical Journal, 2009, 46(5): 585-594. doi: 10.1139/T09-006
[6]	ZHANG Z L, WANG T, WU S R, et al. Seismic performance of loess-mudstone slope by centrifuge tests[J]. Bulletin of Engineering Geology and the Environment, 2017, 76(2): 671-679. doi: 10.1007/s10064-015-0846-2
[7]	孙志亮, 孔令伟, 郭爱国. 风干堆积体边坡地震响应的动力离心模型试验[J]. 岩石力学与工程学报, 2017, 36(9): 2102-2112. doi: 10.13722/j.cnki.jrme.2017.0077 SUN Zhiliang, KONG Lingwei, GUO Aiguo. Dynamic centrifuge tests on seismic responses of air-dried deposit slopes[J]. Chinese Journal of Rock Mechanics and Engineering, 2017, 36(9): 2102-2112. (in Chinese) doi: 10.13722/j.cnki.jrme.2017.0077
[8]	涂杰文, 刘红帅, 汤爱平, 等. 堆积型滑坡地震响应的离心模型试验[J]. 东北大学学报(自然科学版), 2016, 37(5): 736-740. doi: 10.3969/j.issn.1005-3026.2016.05.027 TU Jiewen, LIU Hongshuai, TANG Aiping, et al. Centrifuge model test on the seismic response of colluvial landslide[J]. Journal of Northeastern University (Natural Science), 2016, 37(5): 736-740. (in Chinese) doi: 10.3969/j.issn.1005-3026.2016.05.027
[9]	涂杰文, 刘红帅, 汤爱平, 等. 基于离心振动台的堆积型滑坡加速度响应特征[J]. 岩石力学与工程学报, 2015, 34(7): 1361-1369. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX201507009.htm TU Jiewen, LIU Hongshuai, TANG Aiping, et al. Acceleration response of colluvial landslide based on centrifugal shaking table test[J]. Chinese Journal of Rock Mechanics and Engineering, 2015, 34(7): 1361-1369. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX201507009.htm
[10]	RATHJE E M, BRAY J D. An examination of simplified earthquake-induced displacement procedures for earth structures[J]. Canadian Geotechnical Journal, 1999, 36(1): 72-87. doi: 10.1139/t98-076
[11]	NEWMARK N M. Effects of earthquakes on dams and embankments[J]. Géotechnique, 1965, 15(2): 139-160. doi: 10.1680/geot.1965.15.2.139
[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. https://www.cnki.com.cn/Article/CJFDTOTAL-QHXB200809011.htm YU Yuzhen, LI Rongjian, LI Guangxin, et al. Experimental study on centrifuge model dynamic behavior of slopes with saturated subgrades during earthquakes[J]. Journal of Tsinghua University (Science and Technology), 2008, 48(9): 1422-1425. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-QHXB200809011.htm
[13]	ZHANG Z L, WANG T, WU S R, et al. Investigation of dormant landslides in earthquake conditions using a physical model[J]. Landslides, 2017, 14(3): 1181-1193. doi: 10.1007/s10346-017-0813-z
[14]	ZHANG Z L, WANG T, WU S R, et al. Seismic performance of loess-mudstone slope in Tianshui–Centrifuge model tests and numerical analysis[J]. Engineering Geology, 2017, 222: 225-235. doi: 10.1016/j.enggeo.2017.04.006
[15]	邵帅, 邵生俊, 李宁, 等. 地震作用下黄土边坡震陷破坏的动力离心模型试验研究[J]. 岩土工程学报, 2021, 43(2): 245-253. doi: 10.11779/CJGE202102004 SHAO Shuai, SHAO Shengjun, LI Ning, et al. Dynamic centrifugal model tests on seismic subsidence of loess slopes under earthquake action[J]. Chinese Journal of Geotechnical Engineering, 2021, 43(2): 245-253. (in Chinese) doi: 10.11779/CJGE202102004
[16]	YIN Y P, LI B, WANG W P. Dynamic analysis of the stabilized Wangjiayan landslide in the Wenchuan Ms 8.0 earthquake and aftershocks[J]. Landslides, 2015, 12(3): 537-547. doi: 10.1007/s10346-014-0497-6
[17]	WANG Y S, LUO Y H, WANG F H, et al. Slope seismic response monitoring on the aftershocks of the Wenchuan earthquake in the Mianzhu section[J]. Journal of Mountain Science, 2012, 9(4): 523-528. doi: 10.1007/s11629-012-2179-y
[18]	SHI Z M, WANG Y Q, PENG M, et al. Landslide Dam deformation analysis under aftershocks using large-scale shaking table tests measured by videogrammetric technique[J]. Engineering Geology, 2015, 186: 68-78.
[19]	土工离心模型试验技术规程: DL/T 5102—2013[S]. 北京: 中国电力出版社, 2014. Specification for Geotechnical Centrifuge Model Test Techniques: DL/T 5102—2013[S]. Beijing: China Electric Power Press, 2014. (in Chinese)
[20]	MAVROEIDIS G P. A mathematical representation of near-fault ground motions[J]. Bulletin of the Seismological Society of America, 2003, 93(3): 1099-1131. http://www.nstl.gov.cn/paper_detail.html?id=f0adacbc9f944cb57bc0136366d7e45b
[21]	RATHJE E M, BRAY J D. One- and two-dimensional seismic analysis of solid-waste landfills [J]. Canadian Geotechnical Journal, 2001, 38(4): 850-862.
[22]	KRAMER S L, LINDWALL N W. Dimensionality and directionality effects in newmark sliding block analyses[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2004, 130(3): 303-315.
[23]	GAZETAS G, UDDIN N. Permanent deformation on preexisting sliding surfaces in dams[J]. Journal of Geotechnical Engineering, 1994, 120(11): 2041-2061.