摘要
随着我国经济建设的快速发展,特别是西部大开发战略的实施,西南山区高速铁路建设发展迅速。然而,在西南山区修建高速铁路时,由于地形地质条件的制约和工程建设的需要,在铁路沿线形成大量的路堤边坡及高挖方的路堑边坡。顺层岩质边坡是铁路沿线分布的主要边坡类型之一,降雨诱发的顺层滑坡时有发生,对高速铁路的建设和安全运营构成了巨大的威胁。因而,研究降雨入渗作用下顺层岩质边坡稳定性问题具有重大的现实意义。本文以贵广铁路K307工点为依托,采用相似模型试验和数值模拟手段,较为深入的研究了雨水入渗作用下顺层岩质边坡力学行为的变化规律。论文取得的主要成果如下:
1.对岩质边坡渗流特性进行了分析,探讨了降雨入渗对岩质边坡的作用以及降雨入渗过程,给出降雨作用下含裂隙顺层岩质边坡稳定系数的实用算法,并应用该算法分析具体工程实例。
2.依据相似理论,结合贵广铁路K307原型工点实际,开展了降雨入渗作用下顺层岩质边坡稳定性模型试验研究。拟定了边坡模型与原型的相似比,确定了强风化岩、弱风化岩和软弱夹层相似材料的配合比;根据相似比确定了支挡结构材料;设计了模型试验,确定了传感器的布置方案,建立了边坡试验模型。
3.开展了边坡倾角分别为25°和30°的自然边坡、锚杆框架梁支挡边坡以及锚杆框架梁加抗滑桩支挡边坡的降雨模型试验,研究了降雨入渗作用下坡体软弱夹层含水量、孔隙水压力、坡体位移以及支挡结构内力变化规律,并将不用倾角的边坡在降雨作用下力学特性进行对比分析,结果表明坡体下部位移最大,边坡倾角增大非常不利于边坡稳定,支挡结构对边坡稳定作用明显,不同形式的支挡结构对边坡稳定所起的作用有所差异。
4.基于有限元基本理论,结合建立的边坡模型,采用Midas/GTS岩土数值分析软件分析了不同降雨强度条件下坡体内孔隙水压力分布,分析了降雨入渗过程中的流—固耦合现象,进而分析了降雨入渗作用下边坡稳定性和边坡位移,以及支挡结构内力变化规律,并将数值分析结果与试验结果进行了对比,分析表明两种研究方法得到的总体变化趋势是基本一致的。
As rapid development of China's economy and implementation of the large-scale development strategy for the western region, high speed railway construction develops very rapidly in southwest China. However, a large quantity of embankment slopes and cutting slopes have boomed along railway due to complicated terrain and geological conditions and the necessary of construction during construction of high speed railway in southwest China. The bedded rock slope is one of the familiar types of slopes along railway. The frequent occurrence of bedding landslide induced by rainfall is a big hazard to the construction and operation of high speed railway. Thus it has significant practical meaning to carry on the research on the stability of bedded rock slope due to rainfall infiltration. Based on K307work site, this paper conducts systematical research work on the mechanical behaviors of rock bedded slope under rainfall by the research method of the similar simulation test and the numerical simulation analysis. The main research achievements are as follows:
1. The characteristic of seepage flow for rock slope is analyzed, and the effect of rainfall infiltration on rock slope is studied. This paper also carries on research on the process of rainfall infiltration. The method to calculate stability coefficient of fractured rock slope is given and being used in analyzing project case.
2. According to the similarity theory, combined with project fact of K307work, similarity model test study on the stability of bedded rock slope due to rainfall infiltration have been carried out. The similarity ratio has been constructed and the mix ratio of simulation materials for intensely weathered rock, slightly weathered rock and soft interlayer The material for retaining structure also has been constructed on the basis of similarity ratio. This paper designs model test and decides the layout plan for sensors. The test model has been constructed finally.
3. This paper carries on model tests of natural slope, slope retained by anchor frame beam and slope retained by anchor frame beam and anti-slide pile with slope angle of25°and30°under the condition of rainfall. The change rule of liquid water content, pore water pressure and slope displacement in soft interlayer as internal force of retaining structure during rainfall has been studied and comparative analysis of slope mechanical behaviors with different angles has been done. The achievements shows that the biggest displacement appears at the lower part of slope, the increase of slope angle turns against stability of slope, retaining structure plays an important role in slope stability, and different kinds of retaining structure plays different roles.
4. Based on the finite element theory and combined with the established slope model, Midas/GTS has been used to analyze distribution of slope pore water pressure under different rainfall intensity and change rule of internal force for retaining structure. Furthermore, the stability and displacement of slope during rainfall has been studied. This paper also carries research on internal force of retaining structure during rainfall. The results of numerical analysis were compared with real data obtained from laboratory tests, the results show that changing trends obtained with both methods are basically consistent.
引文
[1]张先发,李明华等.长江上游暴雨与滑坡崩塌关系[J].地理,1995,8(3):101-106
[2]孙广忠.中国典型滑坡[M].北京:科学出版社.1998
[3]张珍,李世海等.重庆地区滑坡与降雨关系的概率分析[J].岩石力学与工程学报,2005,24(17):3185-3191
[4]赵春宏,戴福初等.深圳某填土滑坡破坏机理研究[J].中国地质灾害与防治学报,2007,18(2):1-8
[5]陈峪,王凌等.2003年我国十大极端天气气候事件[J].灾害学,2004,19(3):76-80
[6]林孝松.滑坡与降雨研究[J].地质灾害与环境保护,2001,12(3):1-7
[7]巨能攀,杨建国,黄润秋.108国道新店子滑坡稳定性评价及治理设计[J].地质灾害与环境保护,2001,12(1):54-57
[8]张倬元,王士天,王兰生.工程地质分析原理[M].北京:地质出版社,1993
[9]蒋爵光.铁路岩石边坡[M].铁道出版社,1997
[10]贾娟等.不良地质路堑高边坡的施工模拟与监测分析[J].岩石力学与工程学报,2005.24(22):4106-4110
[11]张友谊.不同降雨条件下峡口滑坡稳定性研究[D].西南交通大学博士学位论文.2007
[12]姚志勇.观音堂隧道高边坡抗滑桩现场监测分析[J].路基工程,2010,3:95-97
[13]谢妮等.黄土路基边坡降雨响应的试验研究[J].四川大学学报,2009(4):31-36
[14]李汝成,王复明.降雨入渗对泥岩-土混填路堤稳定性的影响[J].岩石力学与工程学报,2008(11):2260-2266.
[15]詹良通,吴宏伟等.降雨入渗条件下非饱和膨胀土边坡原位监测[J].岩土力学,2003(2):151-158
[16]周中,傅鹤林等.土石混合体边坡人工降雨模拟试验研究[J].岩土力学,2007(7):1391-1396
[17]孙书伟,朱本珍等.典型顺层高边坡工程病害的地质力学模型试验研究[J].岩土工程学报,2008(9):1349-1355
[18]李焕强,孙红月等.光纤传感技术在边坡模型试验中的应用[J].岩石力学与工程学报,2008(8):1703-1708
[19]朱宝龙,胡厚田等.降雨条件下固体废弃物边坡变形及破坏模式试验研究[J].工程地质学报,2004(3):312-317
[20]沈水进等.降雨作用下路堤边坡的冲刷-渗透耦合分析[J].岩石力学与工程学报,2011(12):2456-2462
[21]林鸿州.降雨诱发土质边坡失稳的试验与数值分析研究[D].清华大学博士学位论文.2007
[22]Huang Ching-Chuan, Ju Yih-Jang,Hwu Lih-Kang,Lee Jin-Long.Internal soil moisture and piezometric responses to rainfall-induced shallow slope failures[J]. Journal of Hydrology 370 (2009):39-51
[23]S. Kawamura, S. Miura, S. Yokohama.Rainfall-induced failure of volcanic slope with crushable particles subjected to freeze-thaw action [J].Geo-Frontiers,2011
[24]钱纪芸等.降雨时黏性土边坡的离心模型试验[J].清华大学学报,2009(6):829-833
[25]姚裕春,姚令侃等.降雨条件下边坡破坏机理离心模型研究[J].中国铁道科学,2004(8):64-68
[26]Adrin Tohari, Makoto Nishigaki,Mitsuru Komatsu.Laboratory Rainfall-Induced Slope Failure with Moisture Content Measurement. Journal of Geotechnical and Geoenvironmental Engineering[J].2007,5:575-587
[27]Ling,Hoe I,Wu Min-Hao,Leshchinsky.Centrifuge modeling of slope instability. Journal of Geotechnical and Geoenvironmental Engineering[J].2009:758-767
[28]Lee Y.S, Cheuk C.Y,Bolton M.D.Instability caused by a seepage impediment in layered fill slopes.Canadian Geotechnical Journal[J].2008:1410-1425
[29]Ng, Charles W.W.Monitoring the performance of unsaturated soil slopes.Special Issue on Laboratory and Field Testing of Unsaturated Soils[J].2008:799-816
[30]Take W A, Bolton M D.Tensiometer saturation and the reliable measurement of soil suction. Geotechnique,2003,53:159-172.
[31]Richards,David J,Powrie,William. Physical modelling of in-ground waste repository capping systems.Proceedings of Institution of Civil Engineers[J].2011:53-65
[32]Jeong,Jaehak,Charbeneau,Randall J.Diffusion wave model for simulating storm-water runoff on highway pavement surfaces at superelevation transition. Journal of Hydraulic Engineering[J].2010:770-778
[33]Moriwakih, Inokuchit,Hattanjit.Failure process in a full-scale landslide experiment using a rainfall simulator[J].Landslides,2004,1(4):277-288
[34]Bolton M D, Take W A, Wong P C P,Yeung F J.Mechanisms of failure in fill slopes after intense rainfall.International Conference on Slope Engineering[J].2003:1-25
[35]Henry Ling,Hoe I Ling.Centrifuge model simulations of rainfall-induced slope Instability [J] Journal of Geotechnical and Geoenvironmental Engineering.2012: 1151-1157
[36]Huei-Tsyr Chen, Wen-Yi Hung,Chin-Chang Chang,Yuan-Ji Chen,Chung-Jung Lee. Centrifuge modeling test of a geotextile-reinforced wall with a very wet clayey backfill[J].Geotextiles and Geomembranes.2007(25):346-359
[37]White D J,Take W A,Bolton M D. Soil deformation measurement using particle image velocimetry (PIV) and photogrammetry[J].Geotechnique.2003(53):619-631
[38]戚国庆,黄润秋等.岩质边坡降雨入渗过程的数值模拟[J].岩石力学与工程学报,2003(22):625-629
[39]刘建华,查旭东等.考虑降雨入渗条件下岩质边坡稳定性分析[J].公路交通科技,2009(10):33-43
[40]吴海真,顾冲时等.饱和非饱和渗流作用下岩石高边坡降雨过程稳定性研究.第五届水利工程渗流学术研讨会论文集,2006
[41]李宏伟.降雨入渗条件下土质边坡非饱和渗流二维数值分析[J].水资源与水工程学报,2009,6(21):133-136
[42]张卓等.岩质边坡在降雨条件下的稳定性分析[J].哈尔滨工大学学报,2009(41):202-205
[43]夏元友,张亮亮.考虑降雨入渗影响的边坡稳定性数值分析[J].公路交通科技,2009,10(26):27-32
[44]C.W.Ng.Three-dimensional numerical investigations of groundwater responses in an unsaturated slope subjected to various rainfall patterns[J].Can Geotech.2001(38): 1049-1062
[45]刘先珊等.降雨过程中的岩质边坡渗流分析及稳定性评价[J].四川大学学报,2007(9):86-90
[46]蒋刚,林鲁生等.降雨渗流作用下残积土边坡的数值分析[J].南京工业大学学报,2005,5(27):27-31
[47]Fei Cai, Keizo Ugai.Numerical Analysis of Rainfall Effects on Slope Stability[J]. International Journal of Geomechanics.2004:69-78
[48]Alonso E, Gen S.Effeet of rain infiltration on the stability of slopes[J].Intemational Academic Publishers,1995:23-25
[49]C W W Ng, Q Shi.A Numerical Investigation of the Stability of Unsaturated Soil Slopes Subjected to Transient Seepage[J]. Computer and Geotechnics.1998:1-28
[50]Harianto Rahardjo,Alfrendo Satyanaga Nio,Eng Choon.Effects of Groundwater Table Position and Soil Properties [J]. Journal of Geotechnical and Geoenvironmental Engineering.2010,9:1555-1564
[51]Gasmo J M, Rahardjo H.Infiltration effects on stability of a residual soil slope[J]. Computers and Geotechnics.2000,26(2):145-165
[52]J.S.L Heureux, K Hoeg.Hoydal.Numerical analyses and field case study of slope Subjected to rainfall[J].Unsaturated Soils.2006:2279-2290
[53]H.Shin, Y.T.Kim, D.K.Park.Development of rainfall hazard envelope for unsaturated infinite slope[J].KSCE Journal of Civil Engineering.2013:351-356
[54]Shimada K, Fujii H, T Mcrii.Stability of unsaturated slopes considering changes of matric suction[J].Unsaturated Soils.1995,1:293-299
[55]Corrado Camera.Rainfall,infiltration,and groundwater flow in a terraced slope of valtellina (Northern Italy):Field Data and Modeling [J].2012(65):1191-1202
[56]刘建军.流体力学[M].北京:北京大学出版社,2006
[57]刘佑荣.岩体力学[M].北京.化学工业出版社,2010
[58]张蔚榛.地下水与土壤水动力学[M].北京:中国水利出版社,1996
[59]曾田.降雨条件下公路路基渗流特性及边坡稳定性分析[D].东南大学.2008
[60]沈明荣.岩体力学[M].上海.同济大学出版社,2006
[61]靳伟,廖延彪,张志鹏等.导波光学传感:原理与技术.北京:科学出版社,1998
[62]邓宏艳.滑坡地段路堑高边坡稳定性分析及支挡结构设计研究[D].西南交通大学硕士学位论文.2005
[63]伍伟林.预应力锚索抗滑桩加固边坡的计算与应用[D].华南理工大学.2010
[64]Fredlund D QRahardjo H.Soil mechanics for unsaturated soils. New York:Wiley Inter, 1993
[65]胡云进.裂隙非饱和渗流试验研究及有地表入渗的裂隙岩体渗流数值分析[D].河海大学博士学位论文.2001
[66]高正夏,赵海滨.岩体软弱夹层渗透变形试验及三维有限元数值模拟[J].水文地质工程地质.2008(1):64-66