基于强度折减法的高土石坝三维抗震稳定分析
|
摘要
在边坡稳定性分析中,虽然极限平衡法因为简单易行而广泛使用,但在处理三维稳定问题时还面临很多困难,而有限元强度折减法处理三维问题要方便得多。本文以应用广泛的岩土工程三维数值模拟工具———FLAC3 D为计算平台,以混凝土面板堆石坝和黏土心墙堆石坝两种坝型为研究对象,在强度折减法基础上采用拟静力方法研究高土石坝坝坡在不同坝高、坝坡坡度、地震烈度以及岸坡坡度条件下的稳定安全系数以及最危险滑裂面的位置和形状。计算结果表明,随着坝高的增加、坝坡的变陡、地震烈度的提高以及岸坡坡度的变缓,坝坡的稳定安全系数均降低。安全系数与坝坡坡比近似呈线性关系,与坝高、地震烈度、岸坡坡度等因素呈非线性特性。基于计算结果,文中给出了安全系数与影响因素之间的经验拟合公式。同时发现,地震烈度和岸坡坡度对面板堆石坝的滑裂面位置和形状有较大影响,而地震烈度对心墙堆石坝滑裂面形状和位置的影响较小。
Although limit equilibrium method has been widely used in stability analysis due to its simplicity,it has shortcomings in dealing with three-dimensional problems,while finite element strength reduction is a more practical technique.In this paper,a strength reduction technique and pseudo-static method based on FLAC3D are applied to dynamic stability analysis of rockfill dams under earthquake conditions to study the effects of dam height,dam slope,earthquake intensity and bank slope on the safety factor and the critical slip surface's location and shape for two types of rockfill dams,concrete-face rockfill dam and earth-core rockfill dam.To reduce computational cost of stability estimation,two fitting functions are proposed for the two dam types,respectively.The analysis reveals that in the concrete-face case,earthquake intensity and bank slope have significant effects,while in the earth-core case,earthquake intensity has little effect.
Although limit equilibrium method has been widely used in stability analysis due to its simplicity,it has shortcomings in dealing with three-dimensional problems,while finite element strength reduction is a more practical technique.In this paper,a strength reduction technique and pseudo-static method based on FLAC3D are applied to dynamic stability analysis of rockfill dams under earthquake conditions to study the effects of dam height,dam slope,earthquake intensity and bank slope on the safety factor and the critical slip surface's location and shape for two types of rockfill dams,concrete-face rockfill dam and earth-core rockfill dam.To reduce computational cost of stability estimation,two fitting functions are proposed for the two dam types,respectively.The analysis reveals that in the concrete-face case,earthquake intensity and bank slope have significant effects,while in the earth-core case,earthquake intensity has little effect.
引文
[1]Bishop A W.The Use of the Slip Circle in the Stability Analysis of Slopes[J].Geotechnique,1955,5(1):7-17.
[2]Donald I B,Giam S K.Application of the Nodal Displacement Method to Slope Stability Analysis[C]//Proceedings of the 5thAustralia-New Zealand Conference on Geomechanics,Sydney,Australia,1988,456-460.
[3]吕擎峰,殷宗泽,王叔华,等.拟静力法边坡稳定分析的改进[J].岩土力学,2005,26(21):35-38.LQingfeng,YIN Zongze,WANG Shuhua,et al.Improvement of pseudo-static method for slope stability analysis[J].Rock andSoil Mechanics,2005,26(21):35-38.(in Chinese)
[4]栾茂田,李湛,范庆来.土石坝拟静力抗震稳定性分析与坝坡地震滑移量估算[J].岩土力学,2007,28(2):224-230,236.LUAN Maotian,LI Zhan,FAN Qinglai.Analysis and evaluation of pseudo-static aseismic stability and seism-induced slidingmovement of earth-rock dams[J].Rock and Soil Mechanics,2007,28(2):224-230.(in Chinese)
[5]左秀泓.关于拟静力法分析土石坝地震稳定性的问题[J].水利水电技术,1991,(7):11-16.ZUO Xiuhong.Study on the stability of soil and rock dams using pseudo-static method[J].Technique of Water Conservancy andHydropower,1991,7:11-16.(in Chinese)
[6]Barton Nick,Kjernsli Bjorn.Shear strength of rock-fill[J].Journal of the Geotechnical Engineering Division,ASCE,1981,107,(7):873-891.
[7]柏树田,崔亦昊.堆石的力学性质[J].水力发电学报,1997,16(3):21-30.BAI Shutian,CUI Yihao.The mechanical properties of rockfill[J].Journal of Hydroelectric Engineering,1997,16(3):21-30.(in Chinese)
[8]Duncan J M.Strength,stress-strain and bulk modulus parameters for finite element analyses of stresses and movements in soil masses[R].Berkeley:Report No.UCB/GT/1980-01,Berkeley University of California,1980.
[9]De Mello V F B.Reflections on design decisions of practical significance to embankment dams[J].Geotechnique,1977,27(3):279-355.
[10]曹克明,陈振文.用非线性强度准则分析堆石坝的稳定性[J].水利水电技术,1991,(8):37-42.Cao Keming,Chen Zhenwen.The stability analysis of rockfill dam using non-linear strength criterion[J].Technique of WaterConservancy and Hydropower,1991,(8):37-42.(in Chinese)
[11]吕擎峰,殷宗泽.非线性强度参数对高土石坝坝坡稳定性的影响[J].岩石力学与工程学报,2004,23(16):2708-2711.LQingfeng,YIN Zongze.Effect of strength nonlinearity on slope stability of high rockfill dam[J].Chinese Journal of Rock Mechanics and Engineering,2004,23(16):2708-2711.(in Chinese)
[12]陈立宏,陈祖煜.堆石非线性强度特性对高土石坝稳定性的影响[J].岩土力学,2007,28(9):1807-1810.CHEN Lihong,CHEN Zuyu.Effect of nonlinear strength of rockfill on slope stability of high earth-rock dam[J].Rock and Soil Mechanics,2007,28(9):1807-1810.(in Chinese)
[13]陈育民,徐鼎平.FLAC/FLAC3D基础与工程实例[M].北京:中国水利水电出版社,2008.CHEN Yumin,XU Dingping.Foundation and engineering examples of FLAC/FLAC3D[M].Beijing:Chinese Water Resources and Hydropower Publisher,2008.(in Chinese)
[14]许春雷.高土石坝坝坡稳定的可靠性研究[D].大连理工大学学位论文,2010.XU Chunlei.Study on reliability of slope stability of high rock-fill dam[D].Master's thesis of Dalian University of Technology,2010.(in Chinese)
[15]中华人民共和国水利部.水工建筑物抗震设计规范SL203-97.北京:中国水利水电出版社,1997.The Ministry of Water Conservancy of the People's Republic of China.Specifications for seismic design of hydraulic structures.Beijing:Chinese Water Resources and Hydropower Publisher,1997.(in Chinese)
[16]程怡.高土石坝三维动力稳定分析研究[D].大连理工大学学位论文,2010.CHENG Yi.Three Dimensional Dynamic Stability Analysis of High Rockfill Dam[D].Master's thesis of Dalian University of Technology,2010.(in Chinese)
[17]YU Yuzhen,XIE Liquan,ZHANG Bingyin.Stability of earth rock-fill dams:Influence of geometry on the three-dimensional effect[J].Computers and Geotechnics,2005,32:326-339.
[18]LIU Jun,CHENG Yi.A Procedure for Searching Three-dimensional Critical Slip Surfaces of Slopes Based on the Strength Reduction Technique[J].Journal of Harbin Institute of Technology,2009,16(supp.1):65-69.
[19]ZHENG Hong,SUN Guanhua,LIU Defu.A practical procedure for searching critical slip surfaces of slopes based on the strength reduction technique[J].Computers and Geotechnics,2009,36:1-5.
[2]Donald I B,Giam S K.Application of the Nodal Displacement Method to Slope Stability Analysis[C]//Proceedings of the 5thAustralia-New Zealand Conference on Geomechanics,Sydney,Australia,1988,456-460.
[3]吕擎峰,殷宗泽,王叔华,等.拟静力法边坡稳定分析的改进[J].岩土力学,2005,26(21):35-38.LQingfeng,YIN Zongze,WANG Shuhua,et al.Improvement of pseudo-static method for slope stability analysis[J].Rock andSoil Mechanics,2005,26(21):35-38.(in Chinese)
[4]栾茂田,李湛,范庆来.土石坝拟静力抗震稳定性分析与坝坡地震滑移量估算[J].岩土力学,2007,28(2):224-230,236.LUAN Maotian,LI Zhan,FAN Qinglai.Analysis and evaluation of pseudo-static aseismic stability and seism-induced slidingmovement of earth-rock dams[J].Rock and Soil Mechanics,2007,28(2):224-230.(in Chinese)
[5]左秀泓.关于拟静力法分析土石坝地震稳定性的问题[J].水利水电技术,1991,(7):11-16.ZUO Xiuhong.Study on the stability of soil and rock dams using pseudo-static method[J].Technique of Water Conservancy andHydropower,1991,7:11-16.(in Chinese)
[6]Barton Nick,Kjernsli Bjorn.Shear strength of rock-fill[J].Journal of the Geotechnical Engineering Division,ASCE,1981,107,(7):873-891.
[7]柏树田,崔亦昊.堆石的力学性质[J].水力发电学报,1997,16(3):21-30.BAI Shutian,CUI Yihao.The mechanical properties of rockfill[J].Journal of Hydroelectric Engineering,1997,16(3):21-30.(in Chinese)
[8]Duncan J M.Strength,stress-strain and bulk modulus parameters for finite element analyses of stresses and movements in soil masses[R].Berkeley:Report No.UCB/GT/1980-01,Berkeley University of California,1980.
[9]De Mello V F B.Reflections on design decisions of practical significance to embankment dams[J].Geotechnique,1977,27(3):279-355.
[10]曹克明,陈振文.用非线性强度准则分析堆石坝的稳定性[J].水利水电技术,1991,(8):37-42.Cao Keming,Chen Zhenwen.The stability analysis of rockfill dam using non-linear strength criterion[J].Technique of WaterConservancy and Hydropower,1991,(8):37-42.(in Chinese)
[11]吕擎峰,殷宗泽.非线性强度参数对高土石坝坝坡稳定性的影响[J].岩石力学与工程学报,2004,23(16):2708-2711.LQingfeng,YIN Zongze.Effect of strength nonlinearity on slope stability of high rockfill dam[J].Chinese Journal of Rock Mechanics and Engineering,2004,23(16):2708-2711.(in Chinese)
[12]陈立宏,陈祖煜.堆石非线性强度特性对高土石坝稳定性的影响[J].岩土力学,2007,28(9):1807-1810.CHEN Lihong,CHEN Zuyu.Effect of nonlinear strength of rockfill on slope stability of high earth-rock dam[J].Rock and Soil Mechanics,2007,28(9):1807-1810.(in Chinese)
[13]陈育民,徐鼎平.FLAC/FLAC3D基础与工程实例[M].北京:中国水利水电出版社,2008.CHEN Yumin,XU Dingping.Foundation and engineering examples of FLAC/FLAC3D[M].Beijing:Chinese Water Resources and Hydropower Publisher,2008.(in Chinese)
[14]许春雷.高土石坝坝坡稳定的可靠性研究[D].大连理工大学学位论文,2010.XU Chunlei.Study on reliability of slope stability of high rock-fill dam[D].Master's thesis of Dalian University of Technology,2010.(in Chinese)
[15]中华人民共和国水利部.水工建筑物抗震设计规范SL203-97.北京:中国水利水电出版社,1997.The Ministry of Water Conservancy of the People's Republic of China.Specifications for seismic design of hydraulic structures.Beijing:Chinese Water Resources and Hydropower Publisher,1997.(in Chinese)
[16]程怡.高土石坝三维动力稳定分析研究[D].大连理工大学学位论文,2010.CHENG Yi.Three Dimensional Dynamic Stability Analysis of High Rockfill Dam[D].Master's thesis of Dalian University of Technology,2010.(in Chinese)
[17]YU Yuzhen,XIE Liquan,ZHANG Bingyin.Stability of earth rock-fill dams:Influence of geometry on the three-dimensional effect[J].Computers and Geotechnics,2005,32:326-339.
[18]LIU Jun,CHENG Yi.A Procedure for Searching Three-dimensional Critical Slip Surfaces of Slopes Based on the Strength Reduction Technique[J].Journal of Harbin Institute of Technology,2009,16(supp.1):65-69.
[19]ZHENG Hong,SUN Guanhua,LIU Defu.A practical procedure for searching critical slip surfaces of slopes based on the strength reduction technique[J].Computers and Geotechnics,2009,36:1-5.
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心