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四川地震灾区陈家山坪崩塌稳定性评价及治理研究
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摘要
5.12汶川地震引发了大量的崩塌次生地质灾害,对山区的城镇、村庄以及各种交通设施等造成了极为严重的破坏,给灾区救援和灾后重建工作带来极大困难。由于次生地质灾害具有滞后效应,所以其发展趋势将是灾后重建所面临的主要问题。地震灾区形成大量松散堆积物,在雨季时,雨水入渗使得本已松散的山体结构强度继续降低,崩塌灾害频繁发生。本论文以四川省什邡市陈家山坪崩塌为研究对象,在收集相关资料的基础上,通过现场调查和勘察,查明崩塌工程地质条件、危岩体基本特征和堆积体的基本特征,采取所需试样进行物理力学试验。对崩塌的形成条件及过程、影响因素和破坏模式进行深入分析。运用Sarma法、Janbu法和传递系数法等极限平衡理论和有限元法对崩塌危岩体的稳定性进行评价,得出稳定性系数、应力等值线图和位移等值线图,并采用Mohr-Coulomb强度理论、Mises理论等屈服准则和拉应力判断分析边坡岩体的屈服破坏情况及拉裂变形特征。然后对崩塌落石运动速度、运动轨迹、腾越距离、弹跳距离、弹跳跳高及缓冲层厚度进行计算。依据计算所得参数,从技术可行和经济合理等方面考虑,对陈家山坪崩塌进行工程治理设计。
5.12 Wenchuan earthquake initiated a large number of collapses secondary geological disasters, causing serious damage to mountain towns, villages and traffic facilities and bringing great difficulty to rescue and reconstruction of disaster areas. Because secondary geological disasters had hysteresis effect, their trend of development would be the main problems before the reconstruction. Earthquake caused a great number of loose deposits. In rainy season, rain infiltration made structural strength of loose mountain continue to decrease and collapses occurred frequently, threatening lives and property of people in disaster areas.
     The paper used Chenjiashanping collapse in Shifang city in Sichuan Province as the research object. Chenjiashanping collapse which occurred in 5.12 earthquake was the second batch of important geological disasters in Sichuan earthquake disaster areas. The collapse formed about 130,000 m3 accumulations and the upper part of the slope remained unstable rock masses, which were easy to produce rolling stones, collapses and slope debris flow threatening lives and property of 31 residents 108 people of shimen village two groups in rainstorm and earthquake conditions.
     On basis of collection of relevant information, through on-site investigations and surveys, the paper found out the engineering geological conditions, the basic characteristics of unstable rock masses and accumulations and took the required samples to do physical and mechanical tests. Formation conditions and processes, influencing factors and failure modes of collapse were deeply analyzed. Limit equilibrium methods including Sarma method, Janbu method and transfer coefficient method and the finite element method were used to evaluate the stability of dangerous rock masses. The stability coefficient and contour map of the stress and displacement were obtained. Mohr-Coulomb strength theory, Mises theory and judgment of the tensile stress were used to analyze the yield failure and tension crack shape characteristics of slope rock masses. Velocity of falling rock, trajectory, distance of collapse, high jump, distance of bounce and thickness of buffer layer were calculated. Based on the calculated parameters, considering technical feasibility, economic rationality and other considerations, regulation projects of Chenjiashanping collapse were designed. The main research results were as follows:
     1. The engineering geological conditions and the basic characteristics of unstable rock masses and accumulations were found out. The formation conditions and processes, influencing factors and failure modes of collapse were deeply analyzed. The formation processes included three stages: formative stage of potential collapse, peristaltic displacement stage of potential collapse and sudden collapse stage. The influencing factors were analyzed: terrain and physiognomy, characteristics of rock and soil, geological structure, earthquake, groundwater and rainfall, weathering and human engineering activities. The main failure mode of Chenjiashanping collapse was sliding-style collapse. Dumping-style collapse, rupture-style collapse and leap-style collapse could be seen.
     2. Back analysis of the shear strength parameters was carried out. Calculation parameters of stability were determined comprehensively. Limit equilibrium theory including Sarma method, Janbu method and transfer coefficient method was used to evaluate the stability of dangerous rock masses and the stability coefficient was obtained. The sensitivity of various factors of stability coefficient was compared. By calculating, W1, W2, W4, W5 dangerous rock masses were at stable state in three conditions. W3 dangerous rock masses were at stable state in natural condition and would be unstable in rainstorm and earthquake conditions. Many block stones on the upper part of dangerous rock masses and accumulations were at unstable state, which were easy to produce falling rocks in rainstorm and earthquake conditions, causing damage to people’s lives and property.
     3. The finite element method was used to evaluate the stability of dangerous rock masses and analyze the slope stress. The slope stress vectorgraph, contour maps of maximum and minimum principal stress, contour maps of shear stress and the maximum shear stress were obtained. The slope deformation was analyzed, and slope displacement vectorgraph, contour maps of horizontal displacement and vertical displacement were obtained. Mohr-Coulomb strength theory, Mises theory and judgment of the tensile stress were used to analyze the yield failure and tension crack shape characteristics of slope rock masses. Through judgment of Mohr-Coulomb strength theory and Mises theory, there was no yield damage area in the slope. By judgment of the tensile stress, tensile stress zone of the slope was found out. By finite element calculation, the stability coefficient was 1.437. The dangerous rock masses were stable. The stability coefficient calculated by Limit equilibrium theory was 1.485. Results calculated by finite element method and limit equilibrium method were basically consistent.
     4. By calculating, velocity of falling rock at the foot of slope was 20.3 ~27.1m/s. The maximum vertical deviation and the maximum horizontal deviation were 2.15m and 4.97m. After rolling stone impacted the road, its high jump and distance of bounce were calculated. The maximum high jump and distance of bounce were 2.21m and 17.59m. Considering calculation results of bounce and vault and according to the terrain of the foot, the minimum distance between retaining wall and the foot of slope was 5m and the height of retaining wall was 2.5 ~ 3.0m. Then thickness of buffer layer was calculated and the thickness of buffer layer was 1.2m.
     5. According to principles of technical feasibility and economic rationality, treatment of Chenjiashanping collapse was carried out. A-type and B-type retaining walls were set at the foot of the slope. The height and length of A-type retaining wall were 2.5m and 183m. The height and length of B-type retaining wall were 3.0m and 183m. Meanwhile, 0.6m×0.6m drains were set and the length was 66m. W3 dangerous rock masses were anchored. The anchoring force calculated was 2365kN/m. The width of unstable rock masses was 20m. Therefore, the total anchor force required was 47300kN. The anchor was composed of 22φj15.24 (7φs5.0) steel hinge line. The anchoring force was 3200kN. The angle of anchor was 15°and the diameter of drilling was 175mm. The length of anchor segment was 11.6m. 15 plum-shaped anchors were needed in 20m width range of the slope.
引文
[1]胡厚田.崩塌与落石[M].北京:中国铁道出版社,1989.
    [2]张路青,杨志法,许兵.滚石与滚石灾害[J].工程地质学报,2004,12(3):225-231.
    [3]刘应辉.汶川地震区都汶公路沿线崩塌滑坡灾害特征与评价[D].兰州:兰州大学,2009.
    [4]李光,姚大全,张有林等.汶川8.0级地震崩塌、滑坡的发育特点[J].防灾科技学院学报,2008,10(3):131-134.
    [5]赵纪生,魏景芝,吴景发等.汶川8.0级地震滑坡、崩塌机制,震灾防御技术[J].2008,3(4):379-383.
    [6]黄润秋,李为乐.汶川地震触发崩塌滑坡数量及其密度特征分析[J].地质灾害与环境保护,2009,20(3):1-7.
    [7]张鹏,李宁,陈新民等.汶川地震山体崩塌破坏特征的分析与启示[J].第三届全国岩土与工程学术大会论文集,696-699.
    [8]赵升,郑明新,王全才.汶川地震引起的老虎嘴山体崩塌形成机理与治理方案分析[J].隧道建设,2009,29(2):243-245.
    [9]袁志辉.延长县崩塌的数值模拟和运动机理研究[D].西安:长安大学,2008.
    [10]曾廉,崩塌与防治[M].成都:西南交通大学出版社,1990.
    [11]张保军,焦发解,左明.白岩危岩体崩塌破坏及其危害性防治[J].岩土力学,2006,27(增):1277-1280.
    [12]骆银辉,胡斌,朱荣华.崩塌的形成机理与防治方法[J].西部探矿工程,2008(12):1-3.
    [13]刘应辉,朱颖彦,苏凤环等.基于地层岩性的崩塌滑坡敏感性分析[J].水土保持研究,2009,16(3):125-130.
    [14]邓广哲.矿山高陡边坡崩塌灾害演化的成因分析[J].岩土力学,2005,26(增):45-48.
    [15]胡厚田,陈彪.崩塌落石区段预测的研究[J].铁道学报,1996,18(4):95-99.
    [16]胡厚田.崩塌落石综合预测方法的研究[J].铁道工程学报,1996(2):182-190.
    [17]旷镇国.重庆市中区危岩崩塌特征、形成机制及防治研究[J].中国地质灾害与防治学报,1995,6(3):51-56.
    [18]高海伟.危岩崩塌的链式演变过程及信息跟踪技术应用[D].重庆:重庆交通大学,2008.
    [19]郭建峰,傅鹤林,周宁等.块体理论在潜在崩塌体稳定性分析中的应用[J].中国地质灾害与防治学报,2006,17(3):14-17.
    [20]田卿燕.块裂岩质边坡崩塌监测预报理论及应用研究[D].长沙:中南大学,2008.
    [21]张管宏.交河故城崖体稳定性及崩塌机理研究[D].兰州:兰州大学,2007.
    [22]何建平,于远忠.川中危岩崩塌稳定分析评价[J].四川建筑科学研究,2007,33(5):69-72.
    [23]胡厚田.崩塌落石研究[J].铁道工程学报,2005(12):387-391.
    [24]夏元友,李梅.崩塌体稳定性检算方法优化研究[J].中国地质灾害与防治学报,2002,13(4):56-58.
    [25]吴超凡,廖英健,戴定贤.福建惠安县石门坑路危岩体崩塌成因分析[J].安徽理工大学学报(自然科学版),2007,27(4):1-4.
    [26]黄永林,顾小宁.层状块体结构岩坡崩塌过程的数值模拟[J].水文地质工程地质,2002(3):10-13.
    [27]李枫.金安桥水电站左岸边坡崩塌体稳定性研究[D].南京:河海大学,2005.
    [28]刘卫华.高陡边坡危岩体稳定性、运动特征及防治对策研究[D].成都:成都理工大学,2008.
    [29]Shi Genhua. Discontinuous deformation analysis-a new numerical model for the statics and dynamics of block system.Dept.of Civil Engineering, University of California, Berkeley: 1988.
    [30]Lanru ling et al. Modeling of fluid and solid deformation for fractured rocks with discontinuous deformation analysis(DDA) method. International Journal of Rock Mechanics and Mining Sciences, Vol.38 No.3, Apr.2001.
    [31]Goodman R.E.and Genhua Shi, The Removability of blocks, Block Theory and its Application to Rock engineering, new jersey, prentice-hell,Inc,1985:98-113.
    [32]岳跃.基于GIS的崩塌地质灾害危险性评价研究[D].上海:同济大学,2008.
    [33]王林峰.群发性崩塌灾害演变理论[D].重庆:重庆交通大学,2008.
    [34]亚南,王兰生,赵其华.崩塌落石运动学的模拟研究[J].地质灾害与环境保护,1996,7(2):25-32.
    [35]沈均,何思明,吴永.滚石灾害研究现状及发展趋势[J].灾害学,2008,23(4):122-125.
    [36]黄润秋,刘卫华.滚石在平台上的运动特征分析[J].地球科学进展,2008,23(5):517-523.
    [37]高云河,雷建海,田景富.流杯池小区危岩落石运动特征分析及其防治建议[J].地球与环境,2005,33(3):150-154.
    [38]赵丽娜,周科平,高峰.露天矿边坡滚石运动特征及控制[J].灾害学,2008,23(3):76-79.
    [39]赵旭,刘汉东.水电站高边坡滚石防护计算研究[J].岩石力学与工程学报,2005,24(20):3742-3748.
    [40]于国新,周安荔.张集铁路玄武岩崩塌落石特征研究[J].铁道工程学报,2008,12(12):9-13.
    [41]胥良,李云贵,刘艳梅.川西108国道高位崩塌成因与运动特征[J].水文地质工程地质,2008(3):28-31.
    [42]张天宝,周良慧.高速公路边坡崩塌落石运动特征分析及防治[J].水电站设计,2009,25(3):40-42.
    [43]唐红梅,易朋莹.危岩落石运动路径研究[J].重庆建筑大学学报,2003,25(1):17-23.
    [44]黄润秋,刘卫华,周江平等.滚石运动特征试验研究[J].岩土工程学报,2007,29(9):1296-1302.
    [45]梁璋彬.崩塌落石的运动特征研究[D].成都:成都理工大学,2008.
    [46]Yoichi Okura,Hikaru Kitahara, Toshiaki Sammori, etc. The effects of rockfall volume on runoutdistance[J].Engineering Geology,2000(58):109-124.
    [47]Joachim Schweigl,Carlo Ferretti. Geotechnical characterization and rockfall simulation of a slope: a practical case study from South Tyrol (Italy) [J]. Engineering Geology, 2003 (67):281-296.
    [48]吕庆.边坡工程灾害防治技术研究[D].杭州:浙江大学,2006.
    [49]赵允辉.危岩崩塌地质灾害调查评价与防治[J].中国地质灾害与防治学报,2004,15(增):33-38.
    [50]向铭,王新民.岩质山体崩塌的岩土工程设计与治理[J].西部探矿工程,2006(12):22-23.
    [51]刘占峰.张集铁路沿线崩塌的工程特性及防治[J].铁道勘察,2007(1):52-55.
    [52]陈秀琼.内昆铁路K249+159右侧岩质边坡崩塌形成机理及整治措施[D].成都:西南交通大学,2007.
    [53]黄勇,陈晓光,刘涛.天山公路边坡崩塌破坏模式及防治对策研究[J].公路交通科技,2008,25(9):271-275.
    [54]石广斌,杨经会,安盛勋等.石泉水电站陡高边坡崩塌机理分析及加固设计[J].岩石力学与工程学报,2004,23(7):1186-1192.
    [55]张中俭,张路青.滚石灾害防治方法浅析[J],工程地质学报,2007,15(5):712-717.
    [56]耿志斌.崩塌边坡稳定性评价及其处治设计[J].西部探矿工程,2007(11):206-207.
    [57]骆银辉,胡斌,朱荣华.崩塌的形成机理与防治方法[J].西部探矿工程,2008(12):1-3.
    [58]贺咏梅,阳友奎.崩塌落石SNS柔性防护系统的设计选型与布置[J].公路,2001(11):14-19.
    [59]蔡洛兵,刘文伟,李念.SNS柔性防护系统技术在江西省三清山环山公路边坡崩塌防护中的应用[J].公路交通科技应用技术版,2007:57-59.
    [60]曾斌,项伟,桂树强.下川岛公路高边坡崩塌落石柔性防护系统设计[J].铁道建筑,2009(9):83-85.
    [61]陈庆华.鹰厦铁路K543崩塌落石病害的整治[J].路基工程,2006(3):146-148.
    [62]谭捍华.明洞在高等级公路崩塌治理中的应用[J].公路,2007(5):16-18.
    [63]徐开祥,黄学斌,付小林等.滑坡及危岩(崩塌)防治工程措施选择与工程设置[J].中国地质灾害与防治学报,2005,16(4):130-134.
    [64]吴新国,温小亚,宋泽峰等.河北省公路沿线崩塌地质灾害类型与发育规律[J].地质灾害与环境保护,2009,20(3):21-27.
    [65]胡斌,黄润秋.软硬岩互层边坡崩塌机理及治理对策研究[J].工程地质学报,2009,17(2):200-205.
    [66]佴磊,薄景山,王世梅.岩土工程数值法[M].长春:吉林大学出版社,1994.
    [67]吕庆,孙红月,翟三扣等.边坡滚石运动的计算模型[J].自然灾害学报,2003,12(2):79-84.

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