青藏工程走廊多年冻土场地地震动加速度峰值特征研究

doi:10.7522/j.issn.1000-0240.2016.0127

摘要/Abstract

摘要： 根据青藏工程走廊北麓河及楚玛尔河场地地震危险性分析结果，合成年超越概率为1.97%、1.00%、0.21%、0.10%、0.04%、0.02%的人造基岩地震波作为输入地震动，结合场地钻孔剖面及波速资料，和已有的冻土动力学研究成果，建立一维模型，通过等效线性化方法进行场地地震反应分析计算，研究了青藏工程走廊多年冻土场地地震动加速度峰值特征及影响因素.研究结果表明，北麓河场地与楚玛尔河场地的人造基岩地震波峰值及持时均存在显著差异，北麓河场地峰值大、持时短，以近震影响为主，楚玛尔河场地峰值小、持时长，以中远震影响为主；多年冻土区场地，夏季场地地震动加速度峰值显著大于冬季，活动层融化对场地地震动加速度峰值有明显的放大效应；冬季场地冻结后，场地地震动加速度峰值随冻土波速增大而减小，最大减小幅度为6.1%，随动剪切模量比减小、阻尼比增大而减小，最大减小幅度为8.9%.活动层的融化有利于放大场地地震动加速度峰值，重大冻土工程抗震设防应予以重视.

关键词: 青藏工程走廊, 多年冻土, 场地地震动加速度峰值, 场地地震反应

Abstract: Based on the results of the seismic hazard analysis of the Beiluhe site and Chumaerhe site along Qinghai-Tibet engineering corridor, artificial bedrock seismic waves with the exceedance probabilities of 1.97%, 1.00%, 0.21%, 0.10%, 0.04%, 0.02% in 1 year were synthesized to use as input waves. One-dimensional model was established by integrating borehole profiles, wave velocities and the existing research results of frozen soil dynamic parameters. Used an equivalent linearity seismic response analysis method, characteristics of site seismic peak ground acceleration(SSPGA) and its influential factors at permafrost sites along Qinghai-Tibet Engineering Corridor (QTEC) were studied. The results show that, (1) peak values and durations of artificial bedrock seismic waves of the Beiluhe site are significantly different from Chumaerhe site, (2) in permafrost site, SSPGA in summer significantly greater than in winter; because the thawed active layer has amplified SSPGA, (3) after frozen in winter, SSPGA decreases with the increase of the frozen soil wave velocity, maximum decrease amplitude is 6.1%, SSPGA decreases with the decrease of G_d/G_dmax and increase of λ, maximum decrease amplitude is 8.9%. The thawing of the active layer has the effect to enlarge SSPGA, so seismic fortification of the major permafrost project should be attached more importance.

Key words: Qinghai-Tibet Engineering Corridor (QTEC), permafrost site, site seismic peak ground acceleration (SSPGA), site seismic response

中图分类号:

P642.14/P315

苏永奇, 马巍, 吴志坚, 马尔曼. 青藏工程走廊多年冻土场地地震动加速度峰值特征研究[J]. 冰川冻土, 2016, 38(4): 1090-1098.

SU Yongqi, MA Wei, WU Zhijian, MA Erman. Study on characteristics of seismic peak ground acceleration at permafrost sites along Qinghai-Tibet Engineering Corridor[J]. JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY, 2016, 38(4): 1090-1098.

参考文献

[1] Zhou Youwu, Guo Dongxin, Qiu Guoqing, et al. Frozen ground in China[M]. Beijing: Science Press, 2000: 42-45. [周幼吾, 郭东信, 邱庆, 等. 中国冻土[M]. 北京: 科学出版社, 2000: 42-45.]
[2] Ma Wei, Niu Fujun, Mu Yanhu. Basic research on the major permafrost projects in the Qinghai-Tibet plateau[J]. Advances in Earth Science, 2012, 27(11): 1185-1191. [马巍, 牛富俊, 穆彦虎. 青藏高原重大冻土工程的基础研究[J]. 地球科学进展, 2012, 27(11): 1185-1191.]
[3] Yin Guo'an, Niu Fujun, Lin Zhanju, et al. The distribution characteristics of permafrost along the Qinghai-Tibet Railway and their response to environmental change[J]. Journal of Glaciology and Geocryology, 2014, 36(4): 772-781. [尹国安, 牛富俊, 林战举, 等. 青藏铁路沿线多年冻土分布特征及其对环境变化的响应[J]. 冰川冻土, 2014, 36(4): 772-781.]
[4] Ruan Guofeng, Zhang Jianming, Chai Mingtang. Risk division of thaw settlement hazard along Qinghai-Tibet Engineering Corridor under climate change[J]. Journal of Glaciology and Geocryology, 2014, 36(4): 811-817. [阮国锋, 张建明, 柴明堂. 气候变化情景下青藏工程走廊融沉灾害风险性区划研究[J]. 冰川冻土, 2014, 36(4): 811-817.]
[5] Liu Minghao, Sun Zhizhong, Niu Fujun, et al. Variation characteristics of the permafrost along the Qinghai-Tibet Railway under the background of climate change[J]. Journal of Glaciology and Geocryology, 2014, 36(5): 1122-1130. [刘明浩, 孙志忠, 牛富俊, 等. 气候变化背景下青藏铁路沿线多年冻土变化特征研究[J]. 冰川冻土, 2014, 36(5): 1122-1130.]
[6] Lin Aiming, Fu Bihong, Guo Jianming, et al. Co-seismic strike-slip and rupture length produced by the 2001 M_s 8.1 Central Kunlun earthquake[J]. Science, 2002, 296(5575): 2015-2017.
[7] Deng Qidong, Cheng Shaoping, Ma Ji, et al. Seismic activities and earthquake potential in the Tibetan Plateau[J]. Chinese Journal of Geophysics, 2014, 57(7): 2025-2042. [邓起东, 程绍平, 马冀, 等. 青藏高原地震活动特征及当前地震活动形势[J]. 地球物理学报, 2014, 57(7): 2025-2042.]
[8] Xu Xiwei, Chen Wenbin, Yu Guihua, et al. Characteristic features of the surface ruptures of the Hoh Sai Hu Kunlunshan Earthquake (M_s8.1), Northern Tibetan Plateau, China[J]. Seismology and Geology, 2002, 24(1): 1-13. [徐锡伟, 陈文彬, 于贵华, 等. 2001年11月14日昆仑山库赛湖地震(M_s8.1)地表破裂带的基本特征[J]. 地震地质, 2002, 24(1): 1-13.]
[9] Xu Xueyan, Xu Chunhua, Li Xiaozhi. Research on earthquake acceleration response spectrum of frozen soil ground[J]. Chinese Journal of Geotechnical Engineering, 2003, 25(6): 680-683. [徐学燕, 徐春华, 李晓稚. 冻土场地地震加速度反应谱研究[J]. 岩土工程学报, 2003, 25(6): 680-683.]
[10] Wang Lixia, Ling Xianzhang, Xu Xueyan, et al. Study on response spectrum characteristics of earthquake acceleration for roadbed on permafrost site[J]. Chinese Journal of Rock Mechanics and Engineering, 2004, 23(8): 1330-1335. [王丽霞, 凌贤长, 徐学燕, 等. 多年冻土场地路基地震加速度反应谱特性研究[J]. 岩石力学与工程学报, 2004, 23(8): 1330-1335.]
[11] Gao Feng, Chen Xingchong, Yan Songhong. Influence of permafrost and seasonally frozen soil on seismic responses of sites[J]. Chinese Journal of Rock Mechanics and Engineering, 2006, 25(8): 1639-1644. [高峰, 陈兴冲, 严松宏. 季节性冻土和多年冻土对场地地震反应的影响[J]. 岩石力学与工程学报, 2006, 25(8): 1639-1644.]
[12] Wu Zhijian, Sun Junjie, Wang Lanmin, et al. Study on characteristics of ground motion at permafrost sites along Qinghai-Tibet Railway[J]. Chinese Journal of Rock Mechanics and Engineering, 2007, 26(12): 2466-2472. [吴志坚, 孙军杰, 王兰民, 等. 青藏铁路沿线冻土场地地震动特征研究[J]. 岩石力学与工程学报, 2007, 26(12): 2466-2472.]
[13] Wang Lanmin, Wu Zhijian, Sun Junjie, et al. Characteristics of ground motion at permafrost sites along the Qinghai-Tibet Railway[J]. Soil Dynamic and Earthquake Engineering, 2009, 29(6): 974-981.
[14] Li Shuangyang, Lai Yuanmin, Zhang Mingyi, et al. Seasonal differences in seismic responses of embankment on a sloping ground in permafrost regions[J]. Soil Dynamic and Earthquake Engineering, 2015, 76(Sl): 122-135.
[15] Qi Jilin, Ma Wei, Sun Chongshao, et al. Seismic response analysis of seasonally frozen ground of Zhangye area[J]. Chinese Journal of Rock Mechanics and Engineering, 2005, 24(12): 2082-2088. [齐吉琳, 马巍, 孙崇绍, 等. 张掖地区季节冻土场地上的地震动效应[J]. 岩石力学与工程学报, 2005, 24(12): 2082-2088.]
[16] Chen Zhuoshi, Li Zhaoyan, Sun Rui. Ground response in seasonal frozen regions under moderate intensity earthquakes[J]. Chinese Journal of Geotechnical Engineering, 2013, 35(S1): 406-411. [陈卓识, 李兆焱, 孙锐. 中等强度地震下季冻区场地响应[J]. 岩土工程学报, 2013, 35(S1): 406-411.]
[17] Zhou Bengang, Chen Guoxing, Gao Zhanwu, et al. The technical highlights in identifying the potential seismic sources for the update of national seismic zoning map of China[J]. Technology for Earthquake Disaster Prevention, 2013, 8(2): 113-124. [周本刚, 陈国星, 高战武, 等. 新地震区划图潜在震源区划分的主要技术特色[J]. 震灾防御技术, 2013, 8(2): 113-124.]
[18] Ma Qinyong, Peng Wanwei, Zhu Yuanlin. Research on relationship among longitudinal and transverse wave velocities and temperature of artificially frozen clay[J]. Chinese Journal of Rock Mechanics and Engineering, 2002, 21(2): 290-293. [马芹永, 彭万巍, 朱元林. 冻结黏土纵、横波速与温度的关系[J]. 岩石力学与工程学报, 2002, 21(2): 290-293.]
[19] Pan Dianqi, Zhang Zupei, Pan Diancai, et al. A test research on longitudinal wave velocity of artificial frozen clay under different temperature and moisture conditions[J]. Journal of Jilin University: Earth Science Edition, 2006, 36(4): 588-591. [潘殿琦, 张祖培, 潘殿彩, 等. 人工冻土纵波波速与温度和含水率的关系[J]. 吉林大学学报: 地球科学版, 2006, 36(4): 588-591.]
[20] Xiao Donghui, Ma Wei, Zhao Shuping, et al. Study of the dynamic parameters of frozen soil: achievement and prospects[J]. Journal of Glaciology and Geocryology, 2015, 37(6): 1611-1626. [肖东辉, 马巍, 赵淑萍, 等. 冻土动力学参数研究的成果综述与展望[J]. 冰川冻土, 2015, 37(6): 1611-1626.]
[21] Wu Zhijian, Wang Lanmin, Ma Wei, et al. Laboratory study on dynamics parameters of frozen soil under seismic dynamic loading[J]. Northwestern Seismological Journal, 2003, 25(3): 210-214. [吴志坚, 王兰民, 马巍, 等. 地震荷载作用下冻土的动力学参数试验研究[J]. 西北地震学报, 2003, 25(3): 210-214.]
[22] Wang Lixia, Hu Qingli, Ling Xianzhang, et al. Experimental study on dynamic shear modulus of remolded frozen silty clay for Qinghai-Xizang Railway[J]. Earthquake Engineering and Engineering Vibration, 2007, 27(2): 177-180. [王丽霞, 胡庆立, 凌贤长, 等. 青藏铁路重塑冻结粉质黏土动剪切模量试验研究[J]. 地震工程与工程振动, 2007, 27(2): 177-180.]
[23] Ling Xianzhang, Zhu Zhanyuan, Zhang Feng, et al. Dynamic elastic modulus for frozen soil from the embankment on Beiluhe Basin along the Qinghai-Tibet Railway[J]. Cold Regions Science and Technology, 2009, 57(1): 7-12.
[24] Zhu Zhanyuan, Ling Xianzhang, Wang Ziyu, et al. Experimental investigation of the dynamic behavior of frozen clay from the Beiluhe subgrade along the QTR[J]. Cold Regions Science and Technology, 2011, 69(1): 91-97.
[25] Ling Xianzhang, Wang Ziyu, Zhang Feng, et al. Experimental investigation on dynamic shear modulus of frozen clay from subgrade of Beijing-Harbin Railway[J]. Chinese Journal of Geotechnical Engineering, 2013, 35(S2): 38-43. [凌贤长, 王子玉, 张锋, 等. 京哈铁路路基冻结粉质黏土动剪切模量试验研究[J]. 岩土工程学报, 2013, 35(S2): 38-43.]
[26] Ling Xianzhang, Zhang Feng, Li Qionglin, et al. Dynamic shear modulus and damping ratio of frozen compacted sand subjected to freeze-thaw cycle under multi-stage cyclic loading[J]. Soil Dynamics and Earthquake Engineering, 2015, 76(Sl): 111-121.
[27] Yuan Xiaoming, Sun Rui, Sun Jing, et al. Laboratory experimental study on dynamic shear modulus ratio and damping ratio of soil[J]. Earthquake Engineering and Engineering Vibration, 2000, 20(4): 133-139. [袁晓铭, 孙锐, 孙静, 等. 常规土类动剪切模量比和阻尼比试验研究[J]. 地震工程与工程振动, 2000, 20(4): 133-139.]
[28] Liao Zhenpeng, Li Xiaojun. Equivalent linearization method for solving the seismic response of the surface soil[C]//Seismic microzonation: theory and practice. Beijing: Seismological Press, 1989: 141-153. [廖振鹏, 李小军. 地表土层地震反应的等效线性化解法[C]//地震小区划: 理论与实践. 北京: 地震出版社, 1989: 141-153.]