隧道地震动力计算边界取值范围研究
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摘要
经典弹性力学中圣维南原理采用解析的方法计算出隧道开挖的影响范围约3倍开挖宽度,这一结论被广泛应用于隧道静力数值计算中。在隧道地震动力时程计算中,计算边界的取值范围除了受到隧道结构的影响,还与边界条件、地震波的输入等其他因素相关,目前学术界还没有较为一致的认识,更没有解析解能计算出动力边界的取值范围。该文利用Flac3D有限差分程序,对不同边界的隧道模型进行动力计算。结果表明:围岩应力值受边界取值范围影响小,围岩位移值受底边界取值范围影响大;并且地震动力计算边界取值大于8倍隧道开挖宽度时,围岩应力及位移受边界取值范围影响可以忽略。研究结论可供隧道动力分析参考。
According to Saint-Venant's principle in classical mechanics of elasticity,tunnel excavation may affect a domain with 3 times the width of excavation,and the conclusion has been widely used in static analysis of tunnel.In the calculation of earthquake dynamic time-history,the model boundaries are not only dependent on the dimension of tunnel structure,but also influenced by the input seismic waves and other related factors.Regarding the dynamic boundary of tunnel model,there has been no consensus,and also no analytical solution can be used.The finite difference software Flac3D adopted to analyze the tunnel models with different boundary ranges.Results show that the boundary has little effect on the stresses of the surrounding rock,while the bottom boundary has an obvious influence on the displacements of surrounding rock.When the boundary of tunnel models has a 8 times width of tunnel excavation in the earthquake dynamic calculations,the boundary effect on the displacement and stresses of surrounding rocks may be ignored.The conclusion may be used as a guideline for future dynamic analysis of tunnels.
According to Saint-Venant's principle in classical mechanics of elasticity,tunnel excavation may affect a domain with 3 times the width of excavation,and the conclusion has been widely used in static analysis of tunnel.In the calculation of earthquake dynamic time-history,the model boundaries are not only dependent on the dimension of tunnel structure,but also influenced by the input seismic waves and other related factors.Regarding the dynamic boundary of tunnel model,there has been no consensus,and also no analytical solution can be used.The finite difference software Flac3D adopted to analyze the tunnel models with different boundary ranges.Results show that the boundary has little effect on the stresses of the surrounding rock,while the bottom boundary has an obvious influence on the displacements of surrounding rock.When the boundary of tunnel models has a 8 times width of tunnel excavation in the earthquake dynamic calculations,the boundary effect on the displacement and stresses of surrounding rocks may be ignored.The conclusion may be used as a guideline for future dynamic analysis of tunnels.
引文
[1]徐芝纶.弹性力学[M].北京:人民教育出版社,1979
[2]潘昌实.隧道力学数值方法[M].北京:中国铁道出版社,1995
[3]李育枢.山岭隧道地震动力响应及减震措施研究[D].上海:同济大学,2006(Li Yushu.Study on earthquakeresponses and vibration-absorption measures for mountaintunnel[D].Shanghai:Tongji University,2006(inChinese))
[4]袁松.地震动力响应下公路隧道合理净距的研究[D].成都:西南交通大学,2009(Yuan Song.Research onreasonble net spacing of highway tunnel under seismicdynamic response[D].Chengdu:Southwest JiaotongUniversity,2009(in Chinese))
[5]邱流潮,金峰.地震分析中人工边界处理与地震动输入方法研究[J].岩土力学,2006,27(9):1501-1504(QiuLiuchao,Jin Feng.Study on method of earthquake inputand artificial boundary conditions for seismic soil-structureinteraction analysis[J].Rock and Soil Mechanics,2006,27(9):1501-1504(in Chinese))
[6]Chen S,Gui M.Seismic performance of tunnel lining ofside-by-side and vertically stacked twin-tunnels[J].Journal of Central South University of Technology,2011,18(4):1226-1234
[7]Genis M.Assessment of the dynamic stability of the portalsof the Dorukhan tunnel using numerical analysis[J].International Journal of Rock Mechanics and MiningSciences,2010,47(8):1231-1241
[8]郭军,王明年,田尚志.高烈度地震区公路隧道明洞抗震计算分析[J].岩土工程学报,2007,29(11):1733-1736(Guo Jun,Wang Mingnian,Tian Shangzhi.Aseismatic analysis on open tunnels of freeway in seismicregion with strong motion[J].Chinese Journal ofGeotechnical Engineering,2007,29(11):1733-1736(inChinese))
[9]黄胜,陈卫忠,杨建平,等.地下工程地震动力响应及抗震研究[J].岩石力学与工程学报.2009,28(3):483-490(Huang Sheng,Chen Weizhong,Yang Jianping,et al.Research on earthquake-induced dynamic responses andaseismic measures for underground engineering[J].Chinese Journal of Rock Mechanics and Engineering,2009,28(3):483-490(in Chinese))
[10]徐华,李天斌.隧道不同减震层的地震动力响应与减震效果分析[J].土木工程学报,2011,44(增1):201-208(Xu Hua,Li Tianbin.Seismic dynamic response anddamping effect analysis of different buffer layers on tunnels[J].China Civil Engineering Journal,2011,44(S1):201-208(in Chinese))
[2]潘昌实.隧道力学数值方法[M].北京:中国铁道出版社,1995
[3]李育枢.山岭隧道地震动力响应及减震措施研究[D].上海:同济大学,2006(Li Yushu.Study on earthquakeresponses and vibration-absorption measures for mountaintunnel[D].Shanghai:Tongji University,2006(inChinese))
[4]袁松.地震动力响应下公路隧道合理净距的研究[D].成都:西南交通大学,2009(Yuan Song.Research onreasonble net spacing of highway tunnel under seismicdynamic response[D].Chengdu:Southwest JiaotongUniversity,2009(in Chinese))
[5]邱流潮,金峰.地震分析中人工边界处理与地震动输入方法研究[J].岩土力学,2006,27(9):1501-1504(QiuLiuchao,Jin Feng.Study on method of earthquake inputand artificial boundary conditions for seismic soil-structureinteraction analysis[J].Rock and Soil Mechanics,2006,27(9):1501-1504(in Chinese))
[6]Chen S,Gui M.Seismic performance of tunnel lining ofside-by-side and vertically stacked twin-tunnels[J].Journal of Central South University of Technology,2011,18(4):1226-1234
[7]Genis M.Assessment of the dynamic stability of the portalsof the Dorukhan tunnel using numerical analysis[J].International Journal of Rock Mechanics and MiningSciences,2010,47(8):1231-1241
[8]郭军,王明年,田尚志.高烈度地震区公路隧道明洞抗震计算分析[J].岩土工程学报,2007,29(11):1733-1736(Guo Jun,Wang Mingnian,Tian Shangzhi.Aseismatic analysis on open tunnels of freeway in seismicregion with strong motion[J].Chinese Journal ofGeotechnical Engineering,2007,29(11):1733-1736(inChinese))
[9]黄胜,陈卫忠,杨建平,等.地下工程地震动力响应及抗震研究[J].岩石力学与工程学报.2009,28(3):483-490(Huang Sheng,Chen Weizhong,Yang Jianping,et al.Research on earthquake-induced dynamic responses andaseismic measures for underground engineering[J].Chinese Journal of Rock Mechanics and Engineering,2009,28(3):483-490(in Chinese))
[10]徐华,李天斌.隧道不同减震层的地震动力响应与减震效果分析[J].土木工程学报,2011,44(增1):201-208(Xu Hua,Li Tianbin.Seismic dynamic response anddamping effect analysis of different buffer layers on tunnels[J].China Civil Engineering Journal,2011,44(S1):201-208(in Chinese))
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