摘要
边坡工程涉及到国民经济建设的各个方面,如露天采矿工程、铁路、公路、水利建设、房屋建筑与市政建设等等,它一方面关系到其所维系的各种构筑物的安全与正常使用,另一方面又影响到构筑物的建设成本。随着人口的急速增长和土地资源的过度开发,边坡问题已成为同地震和火山相并列的全球性三大地质灾害之一。膨胀土是一种吸水膨胀软化、失水收缩开裂的特种粘性土。其主要工程性质是具有裂隙性、超固结性、反复胀缩性。在工程建设中膨胀土作为堤坝的填土材料,可能在堤坝表面产生滑动;膨胀土作为开挖介质,则可能在开挖边坡体时产生滑坡失稳现象。
本文在膨胀土边坡已有研究成果的基础上,对降雨强度、降雨持时以及裂隙开裂深度等对膨胀土边坡稳定性影响的参数进行研究,以期得到考虑与不考虑裂隙时边坡渗流场的变化规律。通过两者对比来说明在进行膨胀土边坡稳定性分析时,考虑裂隙影响的必要性。本文以望江路大蜀山段边坡为例,建立分析计算的力学模型,根据现场试验数据,通过数值模拟的方法,进行边坡稳定分析。本文在边坡稳定分析的基础上,虑及施工情况并参考国内外公路工程实践中的一些支护方法,采用了膨胀土路基边坡处理的多种支挡加固措施和防护手段,并对预应力锚索框格梁与土钉锚固进行了考虑膨胀特性规律的设计计算,并以此为依据探讨了预应力锚索合理间距的问题。
本研究成果在实际施工中得到了较好的应用,取得了较为可观的经济效益和社会效益。
Slope engineering relates to all aspects of national economic construction, such as the open air mining engineering, railroad, highway, water conservancy, construction engineering and civil construction. On one hand it determines the safety and in gear use of all constructions which it supports, on the other hand it influences the cost of the building. With the quick increasing of population and excess exploitation of land resource, slope problem has been one of the three biggest geological disasters and the other two are earthquake and volcano.
Expansive soil is a special dauby soil which will intenerate and expand after sopping, but will shrink and craze after losing water. Its main engineering property is cranny, strong concretion and repeat expansive-shrink, ect. In the engineering construction, expansible soil which is used for filling material will glide on the surface of the dyke, which is used for medium during dig will lose property on the digging slope.
On the basis of expansive side slope research outcome, the paper makes a parameter study of the expansive soil side slope stability affected by rainfall intensity, craze cracking depth and rainfall duration, hoping to get the change law of side slope penetration field under the condition of considering or no considering the cranny. By comparing with two conditions, the paper illustrates the necessity of considering the infection of cranny when analyzing the expansive soil side slope.Based on a case of slope in Wang-Jiang Road, an analytical mechanical model was developed. According to field testing data, the paper made the slope stability analysis by numerical simulation. Then, on the basis of slope stability analysis, construction condition, and some methods in the internal and external road project, the measures of support and defence are provided. The designs of pre-stressed anchor cable with frame beam and anchored soil-nail are given, which are involved in the expansive engineering property. Based on it, the problem of logical space between prestressed cables had discussed.
The study results are properly applied in the construction and some economic benefits and social advantages are obtained.
引文
[1] 中国地质环境信息网http://www.cigem.gov.cn
[2] 任光明,聂德新.大型滑带土结构强度再生特征及其机理探讨[J].地质灾害与环境保护,1997,24(3):28-31.
[3] 周平根.化带土强度参数的估计方法[J].水文地质工程地质,1998,25(6):30-32
[4] 李祥海,胡本刚,廖知勇.新店自滑坡分析及稳定性评价[J].中国地质灾害与防治学报,2000,11(4):45-47.
[5] 于济民.滑坡预测预报技术综述[J].兰州大学学报,1992增刊.
[6] 刘家庆.利用蠕变特征预报岩石滑坡破坏实践的方法探讨.岩石力学,11期.
[7] 晏同珍.滑坡及其预测预报问题[J].兰州滑坡泥石流学术研讨会论文集.兰州:兰州大学出版社,1998:212-214.
[8] 邹兴普.锚索抗滑桩的设计计算[J].路基工程,2000,18(2):9-10.
[9] 余振锡.预应力锚索抗滑桩在滑坡治理中的应用[J].金属矿山,1998,26(4):10-12,27.
[10] 孙玉科.2l世纪中国大型工程与工程地质问题[J].工程地质学报,1995(4).
[11] 孟晖,湖海涛.我国主要人类工程活动引起的滑坡、崩塌和泥石流灾害[J].工程地质学报,1996(4).
[12] 胡鹏,袁华山.边坡稳定性分析的智能方法[J].中国科技信息.2005,(22).
[13] 杨立军,王方.岩质边坡稳定性分析中的几个问题及改进方法[J].西部探矿工程.2005,12.
[14] 徐祯祥等.岩土锚固技术与西部开发[M].北京:人民交通出版社,2002,443-496.
[15] 长江勘测技术研究所.边坡检测书记处理预报软件研究纪应用,1995.3.
[16] 廖世文.膨胀土与铁路工程[M].北京:中国铁道出版社,1984.
[17] 刘小丽,张占民,邓建辉.边坡加固中预应力锚索框架地梁的杆系有限元分.析[J].岩土力学,2004,7(25).
[18] 杨志庆,等.预应力锚索框架梁结构在边坡治理中的应用[J].探矿工程一岩土钻掘工程.2005,2.
[19] 吴乾荣.某地膨胀土中蒙脱石的X射线衍射K值法定量分析[J].地质实验室,1989.5(4):242-243.
[20] 李佩玉,袁慰顺,等.对影响蒙脱石层间距诸因素的探索[J].中国地质科学院南京地质矿产研究所所刊,1986.7(1):61.
[21] 张秋菊.蒙脱石X射线及热重度定量分析方法试验[J].湖南地质,1989.8(1):71-77.
[22] 刘彬.新疆托克逊膨胀土胶体的某些物理化学性质[J].光谱学与光谱分析,1998.18(1):58-62
[23] 林极峰等.贵州盘县地区膨胀土矿产出地质特征及其物化性能研究[J].贵州地质,1989,6(4):21-33
[24] 宋玉梅等.山西浑源膨胀土岩石矿物特征及工艺性能研究[J].山西地质,1992,7(1):1-15.
[25] 林晓峰,王观虎.机场膨胀土土基处理方法研究[C].膨胀土处治理论、激素与实践.北京:人民交通出版社,2004,12.
[26] 谭罗荣,张梅英,邵悟敏等.灾害性膨胀土结构特性及其工程性质[J].岩土工程学报,1994,16(2):67-81
[27] 孙长龙,般宗泽等.膨胀土性质研究综述[J].水利水电科技进展,1995,(12).
[28] Bjerrum L Progressive failure in slopes of over consolidated plastic clay [J].Journal Soil Mesh and Foundation Div ASCE,1967,93(5):3-50.
[29] 卢再华等.原状膨胀土的强度变形特征及其本构特征研究[J].岩土力学,2001,22(3):339-342.
[30] 耿建彬.膨胀土地区地裂的形成发育及其危害防治[J].岩土工程技术,1998(1):21-23.
[31] 孙惠兰,徐培华.高等级公路膨胀土地段路基施工技术[J].筑路机械与施工机械化,1999,(4).
[32] 缪林昌,刘松玉.论膨胀土的工程特性及工程措施[J].水利水电科技进展,2001,(4).
[33] 孔官瑞.膨胀土边坡稳定性试验及数值分析[D].武汉水利水电大学学位论文,1993.
[34] Skempton A W. Fourth rankine lecture long term stability of clay slopes[J].Geotechnique,1964,14(2):231-242.
[35] Bishop A W, Bjerrum. The relevance of the triaxial test to the solution of stability problems[J]. Research Conf on Shear Strength of Cohesive Soils,ASCE, 1960, 75(3):437-501.
[36] 潘君牧.由堑坡体求算裂隙土抗剪强度[A].工程建设中膨胀土问题[M].水利水电科技进展,2001,21(2):37-40.
[37] 廖济川.膨胀土抗剪强度研究概况[A].全国首届膨胀土科学研讨会论文集[c].成都:西南交通大学出版社,1990.
[38] BISHOP A W ,BLIGHT G E. Some aspects of effective stress in saturated and partly saturated soils[J] Geotechnique, 1962, 12(2): 125-144.
[39] FRELUNDG , RAHADJOH. Soil mechanics for unsaturated soils[M]. New York: John Wiley & Sons, 1993.
[40] 卢肇钧等.膨胀力在非饱和土强度理论中的应用[J].岩土工程学报,1997,19(5):20-27.
[41] 缪林昌,殷宗泽.非饱和土的剪切强度[J].岩土力学,1999,21(3):1-6.
[42] 谢宝玉,郝中海.膨胀土路基处理技术[M].公路,2001,7(7).
[43] GBJ112-87,膨胀土地区建筑技术规范[S].
[44] JTGD30-2004,公路路基设计规范[S].
[45] 谭罗荣,张梅英,邵悟敏等.风干含水量W65用作膨胀土判别分类指标的可行性研究[J].工程地质学报,1994,2(1).
[46] 姚海林,杨洋,程平,等.膨胀土壤标准吸湿含水率及其试验方法[J].岩土力学,2004,25(6).
[47] JTJ013-95,公路路基设计规范[S].
[48] 刘特洪.工程建设中的膨胀土问题[M].北京:中国建筑工业出版社,1997.
[49] 李生林,秦素娟,薄遵昭,等.中国膨胀土工程地质研究[M].南京:江苏科学技术出版社,1992,151-158.
[50] 杨涛,纪桂霞.路基膨胀土胀缩等级综合评判等[J].华东公路,2002,6(3).
[51] 黄卫,钟理,钱振东.路基膨胀土胀缩等级的模糊评判[J].岩土工程学报,1999,21(4):408-413.
[52] 陈新民.膨胀土判别土分类的灰色关联法[J].岩土力学,1996,17(4):30-34.
[53] 梁俊勋.用灰色聚类法判别膨胀土等级的初步尝试[J].工程勘察,1992,(2):26-28.
[54] 崔政权,李宁.边坡工程——理论与实践最新发展[M].北京:中国水利水电出版社,1999.
[55] 张梅英,谭罗荣,邵悟敏等.南方膨胀土的微观结构特性与工程性质研究[J].岩土力学,1993,14(1):67-81.
[56] 陈祖煜.土质边坡稳定分析——原理方法程序[M].北京:中国水利水电出版社.2003.
[57] Hoek E. General two dimensional slope stability analysi [A]. Analytical and Computational Methods in Engineering Rock Mechanics[C]. 95-Allen and Unwin, London, 1987.
[58] 王勤成,邵敏.有限单元法基本原理和数值方法[M].北京:清华大学出版社,2002:38-258.
[59] Ghaboussi j r & Barboo sa R. Three-dimensional and discrete element methods for granular material. Int J Nomer. Anal methods Geomech, 1990, 14:451-472.
[60] 张有天.岩石高边坡的变形与稳定[M].北京:中国水利水电出版社,1999:117-276.
[61] 石根华.数值流形方法与非连续变形分析[M].裴觉民译.北京:清华大学出版社,1997:92-204.
[62] Christian J.J.,Ladd, C.C.,and Baecher, G.B. Reliability in stability analysis, in stability and performance of Slopes and Embandments. ASCE Geotechnical Special Publications, 1992. Vol. 12:1071-1111.
[63] 祝玉学.边坡可靠性分析[M].北京:冶金工业出版社,1993.
[64] 胡宝清.模糊理论基础[M].湖北:武汉大学出版社,2004.
[65] 肖盛燮,王平义,吕恩琳.模糊数学在土木与水利工程的应用[M].北京:人民交通出版社,2005.
[66] 李彰明.模糊分析在边坡稳定性评价中的应用[J].岩石力学与工程学报,1997,16(5):490-495.
[67] 邓聚龙.灰色系统基本方法[M].武汉:华中理工大学出版社,1987.
[68] 刘沐宇,朱瑞赓.基于模糊相似优先的边坡稳定性评价范例推理方法[J].岩石力学与工程学报,2002,21(8):1188-1193.
[69] 陈新民,罗国煜.基于经验的边坡稳定性灰色系统分析与评价[J].岩土工程学报,1999,21(5):638-641。
[70] 朱大奇,史慧.人工神经网络原理及应用[M].北京:科学出版社,2006。
[71] D G 弗雷德隆德,H 拉哈尔佐.非饱和土土力学[M].陈仲颐等译.北京:中国建筑工业出版社,1997.392~405.