三峡库区万州区滑坡发育规律及风险研究

发布时间：2018-05-08 00:39

本文选题：滑坡 + 风险　；参考：《中国地质大学》2014年博士论文

【摘要】：滑坡因其具有多发性和频发性的特点,已成为地质灾害中的一个重要灾种,其严重的破坏性,不仅给灾害易发区人民生命及财产安全带来威胁,还对环境、社会、经济造成了诸多不良影响,尤其在过去的三十年,随着人口增长和土地利用扩张,滑坡及其次生灾害(如滑坡涌浪、滑坡坝、堰塞湖等)已造成了大量的人员伤亡和经济损失。我国是世界上受地质灾害影响最严重的国家之一,近五年来,地质灾害以平均每年2万起的规模发生,造成了年均1273人伤亡及失踪,年均直接经济损失达41.43亿元。依据《全国地质灾害通报》中2005年以来的数据统计发现,我国滑坡灾害发生数量占全年总灾害数量的百分比,年均达65%,2006年所占百分比最高,为86%。近期,如2012年《全国地质灾害通报》表明,该年全国共发生地质灾害14322起,造成直接经济损失52.8亿元,其中滑坡灾害发生数量占据总灾害数的76%。长江三峡库区因其复杂的自然条件和地质环境,历来是地质灾害多发区。自2003年6月以来,三峡水库经历了正式蓄水、库水位逐年抬升并达到设计蓄水位的库水位调度过程,在此期间,库区内地质灾害时有发生、隐患点明显增多。据2010年的相关报道显示,库区已知的崩塌滑坡地质灾害隐患点达5386处。目前,虽然随着三峡库区二、三期地质灾害防治项目的完成,已有887处城镇及居民集中区的地质灾害点采取了相应的工程治理措施,但是仍有大量地质灾害隐患点需要依靠人工监测的方式实现灾害防御。因此,鉴于三峡工程重要的政治、经济、社会地位和库区城镇发展的需要,探明该区滑坡发育规律,尤其是探明在库水位调度和大规模城市建设的大环境下,库岸滑坡失稳和古滑坡复活将会带来的灾害风险问题,对保障库区人民生命及财产安全,促进库区城镇发展具有重要意义。重庆市万州区是三峡库区的腹心之地,其特殊的地质环境为滑坡的发育和发生提供了有利条件。鉴于万州区滑坡发育具有分布广、频率大的特点,论文将围绕该区的滑坡灾害问题展开研究和讨论：在探明万州区滑坡发育规律的基础上,基于目前国内外学者普遍接受的风险分析理论和流程,采用理论分析与实例计算相结合的方式,开展了不同尺度的滑坡灾害风险研究。目前,在滑坡发育规律及变形破坏机理研究方面,主要存在的问题包括：如何保障滑坡基础资料的完整性和准确性、如何提高滑坡发育时空预测的可靠性、如何界定滑坡发育特征的时效性、如何统一滑坡变形破坏类型分类标准、如何模拟真实的实验环境以及合理进行数值模拟分析,等。在滑坡灾害风险研究方面,主要存在的问题包括:滑坡风险研究的时间尺度如何界定、滑坡风险研究的空间动态性如何表达、运用传统的破坏概率计算方法如何反应三峡库区中常见的蠕滑型滑坡的局部破坏概率、如何提高风险成果的可信度以及如何加强和完善风险管理工作,等。论文针对目前研究中存在的部分问题,在充分收集和整理万州区滑坡灾害相关资料的基础上,重点在滑坡规模发育规律、区域滑坡易发性分析和单体滑坡局部破坏概率分析方面进行了探讨。通过完成万州区滑坡灾害发育规律分析和不同尺度滑坡灾害风险分析,论文主要取得了以下成果和结论： (1)综合考虑滑坡发育的地质环境条件和滑坡发育的形态规模特征,进行三峡库区万州区滑坡发育规律分析。基于万州区最新和最完整的地质灾害排查资料,进行万州区滑坡灾害的发育规律分析,主要从滑坡发育的地质环境分析和滑坡形态规模尺寸分析两个方面进行。滑坡发育地质环境条件的分析主要包括滑坡的分布高程、地形地貌、水文地质条件、滑坡边界条件和滑坡物质组成及地层年代等；滑坡形态规模分析包括滑坡的平剖面形态和滑坡的尺寸(长、宽、面积、体积)等。通过分析滑坡在上述各项内容中的分布情况,总结万州区已知滑坡的发育特征和规律。 (2)基于滑坡发育的规模尺寸,进行三峡库区万州区滑坡发育规模尺寸间的关系分析。根据论文所收集得到的滑坡发育规模尺寸指标(滑坡最大长度、平均宽度、面积和体积)的分布数据,探讨各指标间的关系,主要得出：万州区,无论是涉水型,还是非涉水型滑坡,滑坡发育长度与其宽度的相关性不明显,且通常不发育为在长宽方向上同时具有极大值的滑坡；滑坡发育面积与其长度(宽度)之间具有一定的相关性,滑坡发育面积较大的滑坡,其长度(宽度)也相应发育较大,但随着滑坡发育面积增大,滑坡面积与其长度(宽度)分布图的离散性越明显、相关性越低；滑坡发育体积也满足体积越大,其发育长度和宽度相应较大的特点,但是滑坡体积与滑坡长度(宽度)分布图的离散性更强、相关性较差；滑坡发育体积与面积的相关性相对较好,滑坡体积发育较大时,其发育面积也相应较大,此外,滑坡发育规模增大,滑坡分布数量相应减少,滑坡体积与面积分布图表现出离散性的分布特征、相关性降低。 (3)从分析滑坡发生频率密度与规模关系的角度,进行三峡库区万州区滑坡规模发育规律研究。论文将万州区滑坡编录数据分为全区滑坡、涉水型滑坡和非涉水型滑坡三组数据,分别探讨了各组数据中滑坡发生频率密度-规模分布函数方程及拟合曲线。所得结果表明,万州区滑坡发生频率密度-规模分布满足三参数反伽马函数的概率密度分布,并在较大滑坡规模尺寸上满足非累计幂指数函数分布；万州区滑坡规模往往集中发育在一定尺寸范围内,其中非涉水型滑坡在发育规模(宽度、面积、体积)上较涉水型滑坡集中性更强、涉水型滑坡发育为较大规模(宽度、面积、体积)滑坡的可能性更大。此外,通过对比依据不同地区、不同事件诱发下滑坡发生记录得到的滑坡发生频率密度-规模关系分布曲线发现,滑坡发生频率密度-规模关系分布规律具有普适性；滑坡发育受到地质环境和外界因素的控制,其发育规模具有集中于某范围尺寸间分布的特征,滑坡编录数据越完整,滑坡发生频率密度-规模分布曲线越接近基于初始完整滑坡数据所得分布曲线。 (4)基于聚类模型,结合万州区地质环境资料、滑坡分布资料,以及滑坡发生频率密度-规模拟合曲线,进行三峡库区万州区滑坡危险性分析。论文首先选择地层年代、高程分布等七个指标作为万州区滑坡易发性分析的评价指标,同时,统计分析已知滑坡在各指标中分布的栅格数据,得到各个评价指标的滑坡易发性等级分布图。其次,基于熵权法和层次分析法的综合评判法,进行万州区滑坡易发性各评价指标的权重计算,得出,地层年代和地形坡度指标对万州区滑坡易发性分析影响最大。再则,选择聚类模型和信息量模型进行万州区滑坡灾害易发性区划,实现了聚类模型算法编写、优化了聚类模型只分类不分级的问题。通过对比两种模型所得滑坡易发性区划结果,信息量模型的区划精度高于聚类模型,但结果过于保守,聚类模型的预测结果更贴近实际情况。最后,结合万州区滑坡分布图和滑坡发生频率密度-规模分布曲线,在进一步修正滑坡易发性区划图的基础上,得到万州区滑坡危险性区划图。总体来看,万州区具有江南区滑坡极高危险区较江北区滑坡极高危险区分布面积广、主城区及长江上游部分地区滑坡极高危险区分布较为集中以及长江下游地区滑坡高危险区呈零星分布的特征。 (5)在统计万州全区承灾体及其价值、人口密度分布情况的基础上,进行万州全区滑坡风险分析。万州区承灾体划分为人口、房屋建筑物、交通道路和土地资源四大类。通过分析万州区承灾体易损性,得到：从整体上看,万州主城区的承灾体易损性较大；人口易损性等级分布与滑坡危险性等级分布一致；房屋建筑易损性等级最高的区域集中分布于主城区沿长江、竺溪河交界处的,较高易损性的房屋在滑坡危险性等级为极高的区域内成零星散布；交通道路的易损性等级表现出段状分布的特征,整体上看,交通道路类型级别越高,其抗灾害能力越强,相同等级灾害强度作用下,易损性越小；主城区附近土地资源的易损性等级最高,其余易损性较高的区域与滑坡危险性等级为较高的区域分布基本一致。综合该区经济价值和人口密度分布信息,分析得到万州全区滑坡灾害风险无论是人口风险还是经济风险,主城区的滑坡灾害风险最大。 (6)基于加卸载响应比模型,进行三舟溪滑坡地表位移与降雨、库水位响应关系分析。结合三舟溪滑坡GPS地表位移监测资料、降雨及库水位调度资料,运用加卸载响应比模型,探讨了滑坡地表变形与其影响因素之间的响应关系,主要得出：三舟溪滑坡变形加卸载响应比能较好的表征滑坡点的稳定性状况及其变形时段特征；该滑坡处于整体基本稳定、局部欠稳定状态；降雨对该滑坡变形具有促进作用,而与库水位作用比较而言,库水位升降作用对该滑坡的影响更大；从整体上看,三舟溪滑坡在库水作用上表现出中前部先响应变形,中后部后响应变形的牵引式变形特征。 (7)基于分形理论中的计盒模型,进行三舟溪滑坡地表位移监测点运动轨迹分形维数计算,进而基于反距离插值法,进行三舟溪滑坡变形分形维数分区。首先,根据三舟溪滑坡地表位移各监测点的GPS监测数据,分析和整理监测点地表位移轨迹曲线；其次,以全年和库水位涨落为计算周期,对各监测点的位移轨迹进行分段；然后,对各监测点分段后的位移轨迹曲线进行图像处理和转换,得到各个运动轨迹分段曲线的灰度图像；再则,利用计盒模型计算各个灰度图像的分形维数；最后,采用反距离插值法(IDW)得到滑坡变形各周期阶段的分形维数分区图。所得分形维数分区图表明：三舟溪滑坡从整体上看在库水位下降期变形较库水位上升期变形严重,从局部上看,滑坡的局部变形受到库水位升降作用的综合影响,不同滑坡部位受库水位升降作用的影响程度不同,在库水位涨落期间,滑坡右侧变形较左侧大、中前部变形较滑坡中后部大。 (8)结合GeoStudio滑坡整体破坏概率计算、滑坡变形分形维数分区图、滑坡发育的地质环境特征以及滑坡现场宏观变形调查数据,进行三舟溪滑坡局部破坏概率分析。论文主要运用GeoStudio数值模拟软件中的SEEP/W功能模块,进行在降雨和库水位共同作用下,三舟溪滑坡在不同年不同库水升降调度周期中地下水位的瞬态模拟,进而耦合SLOP/W功能模块计算三舟溪滑坡在不同计算周期中各模拟地下水位线所对应的滑坡整体破坏概率,按照各计算周期中地下水位线模拟结果的合理性和滑坡稳定性系数最小为原则选择表征该计算周期的滑坡整体破坏概率。此外,根据三舟溪滑坡发育的地质环境特征和滑坡现场调查数据,基于滑坡变形分形维数分区图,修正得到实际中滑坡局部变形的边界形态,进而依据滑坡局部变形的严重程度和滑坡整体破坏概率大小及计算剖面线的位置,定性-半定量分析该滑坡的局部破坏概率。所得三舟溪滑坡局部破坏概率分布图表明：三舟溪滑坡局部破坏概率分布图能较好的反应该滑坡在库水位上升和下降两种工况下的局部变形状态；滑坡右侧危险性较左侧大；整体上看,滑坡在库水位下降期间的危险性高于库水位上升期；同时,结合库水位下降和库水位上升两种工况中,滑坡破坏概率较高的区域与地裂缝展布位置的关系,可以推测,滑坡地表直线形、垂直主滑方向排列的裂缝可能是库水位升降综合作用下滑坡局部变形拉裂的结果,而弧形、由垂直主滑方向向平行主滑方向发育的裂缝更可能是库水位下降时期滑坡局部变形拉裂的结果。 (9)基于三舟溪滑坡承灾体及其经济价值、人口数量分布资料,进行该滑坡的风险分析。论文按照库水位涨落周期,探讨了三舟溪滑坡的风险,主要考虑的承灾体对象为该滑坡范围内的房屋建筑、室内人口和农田及杂草地。所得不同库水位涨落工况下滑坡风险分析结果表明：从总体上看,三舟溪滑坡库水位下降期滑坡灾害风险高于库水位上升期；对于该滑坡范围内房屋建筑经济价值风险来说,库水位下降期风险总体上高于库水位上升期,在库水位下降期,房屋建筑经济价值风险为0.28至10.1万元,而在库水位上升期,房屋建筑经济价值风险为0.16至2.8万元；对于滑坡范围内室内人口风险来说,部分房屋室内人口风险在库水位下降期高于库水位上升期,在库水位上升期,滑坡范围内室内人口风险共计4人,库水位下降期共计8人；此外,对于其他农用及杂草地的价值风险来说,库水位下降期,滑坡体不同部位土地经济价值风险为933至2160元/亩,库水位上升期,滑坡体不同部位土地经济价值风险为107至933元/亩。
[Abstract]:The landslide and its secondary disasters ( such as landslide swell , landslide dam , dammed lake , etc . ) have caused a great deal of casualties and economic losses . In recent three decades , with the increase of population and the expansion of land use , landslide and its secondary disasters ( such as landslide surge , landslide dam , dammed lake , etc . ) have caused a large number of casualties and economic losses . In recent years , as population growth and land use expansion , landslide and its secondary disasters ( such as landslide surge , landslide dam , dammed lake , etc . ) have caused a large number of casualties and economic losses . In recent years , as population growth and land use expansion , landslide and its secondary disasters ( such as landslide surge , landslide dam , dammed lake , etc . ) have caused a large number of casualties and economic losses .

Since June 2003 , the three gorges reservoir has experienced a large number of geological hazards in the three gorges reservoir area .

The Wanzhou District of Chongqing is the hinterland of the Three Gorges Reservoir area . The special geological environment provides favorable conditions for the development and occurrence of the landslide . In view of the wide distribution and high frequency of the landslide development in Wanzhou area , the paper will study and discuss the landslide hazard problem in this area . Based on the risk analysis theory and process commonly accepted by scholars both at home and abroad , this paper studies the landslide hazard risk in different scales based on the combination of theory analysis and case calculation .

At present , in the research of landslide development law and deformation damage mechanism , the main problems include how to guarantee the completeness and accuracy of landslide datum , how to improve the reliability of landslide development characteristics , how to unify the classification standard of landslide risk research , how to simulate the real experimental environment and reasonable numerical simulation analysis , etc . In the research of landslide hazard risk , how to simulate the local damage probability of the common creeping landslide in the Three Gorges Reservoir area , how to improve the credibility of the risk result and how to strengthen and perfect the risk management , etc .

Based on the analysis of landslide hazard development and the risk analysis of landslide hazard in different scales , the following achievements and conclusions are obtained .

( 1 ) Based on the most recent and most complete geological disaster mapping data in Wanzhou area , the development law of landslide disaster in Wanzhou area is analyzed . Based on the latest and most complete geological disaster mapping data of Wanzhou district , the paper makes a study on the development law of landslide hazard in Wanzhou district .
The shape scale of the landslide includes the flat section shape of the landslide and the size ( length , width , area , volume ) of the landslide . By analyzing the distribution of the landslide in the above - mentioned contents , the development characteristics and laws of the known landslide in Wanzhou area are summarized .

( 2 ) Based on the scale dimension of the development of the landslide , the relationship between the size and size of the landslide development in Wanzhou area of the Three Gorges Reservoir area is analyzed . Based on the data collected from the paper , the relation between each index is discussed .
There is a certain correlation between the area of landslide development and its length ( width ) , the landslide with large area of landslide , its length ( width ) is also correspondingly developed , but with the increase of the development area of the landslide , the greater the discreteness of the distribution map of the landslide area and its length ( width ) , the lower the correlation ;
The larger the volume of landslide , the larger the length and width of the landslide , but the difference between the landslide volume and the landslide length ( width ) is stronger and the correlation is poor ;
The correlation between the volume and area of the landslide is relatively good , and the development area of the landslide is relatively large when the volume of the landslide is relatively large , furthermore , the development scale of the landslide is increased , the number of the landslide distribution correspondingly decreases , the landslide volume and the area distribution map show the distribution characteristics of the discreteness , and the correlation is reduced .

( 3 ) Based on the analysis of the relationship between frequency density and scale of landslide , the paper divides the data into three sets of data of landslide , water - related landslide and non - water - related landslide in the Three Gorges Reservoir area . The results show that the frequency density - scale distribution of landslide in Wanzhou district meets the probability density distribution of three - parameter inverse gamma function , and the distribution of non - cumulative power exponential function is met on the scale of larger landslide .
It is found that the frequency density - scale relation distribution law of the landslide has universality .
The development of the landslide is controlled by the geological environment and the external factors . The development scale of the landslide is characterized by the distribution of a certain range of dimensions . The more complete the landslide inventory data , the closer the frequency density - scale distribution curve of the landslide occurs , the closer the distribution curve is obtained based on the initial complete landslide data .

( 4 ) Based on the clustering model , the landslide hazard analysis of Wanzhou district in the Three Gorges Reservoir area is made by combining the geological environment data , landslide distribution data and landslide occurrence frequency density - scale fitting curve in Wanzhou district .

( 5 ) The risk analysis of landslide risk in Wanzhou is carried out on the basis of statistics of the disaster - bearing body and its value and population density distribution in the whole area of Wanzhou . The disaster - bearing body of Wanzhou District is divided into four categories : population , house building , traffic road and land resource .
The distribution of population vulnerability is consistent with the distribution of landslide hazard grade ;
The most vulnerable areas of the buildings are distributed in the main urban areas along the Yangtze River and the Zhuxi River junction , and the houses with high vulnerability are scattered scattered in the areas with extremely high risk of landslide .
The vulnerability level of traffic road shows the characteristics of segment distribution . As a whole , the higher the level of traffic road type , the stronger the disaster - resistant ability , the less the vulnerability of the same grade disaster intensity .
The vulnerability of the land resources near the main urban area is the highest , and the region with higher vulnerability is basically the same as the regional distribution of the landslide hazard grade . The economic value and the population density distribution information of the comprehensive district are analyzed to obtain the landslide hazard risk in the whole area of Wanzhou , whether the population risk is the economic risk , and the landslide disaster risk is greatest in the main urban area .

( 6 ) Based on the loading / unloading response ratio model , the relationship between surface displacement and rainfall and reservoir water level of Sanzhou xi landslide is analyzed . Based on the data of GPS surface displacement monitoring data , rainfall and reservoir water level dispatching data of Sanzhou xi landslide , the response relation between the surface deformation of landslide and its influencing factors is discussed .
the landslide is in an overall basically stable state and is partially under - stable state ;
The effect of water level rise and fall on the landslide is bigger than that of reservoir water level .
As a whole , the Sanzhou - xi landslide is characterized by the deformation of the middle front part firstly in response to deformation , and the back - rear response deformation of the middle part .

( 7 ) Based on the box model in the fractal theory , the fractal dimension of the movement locus of the surface displacement monitoring points of the Sanzhou xi landslide is calculated , and then , based on the inverse distance interpolation method , the fractal dimension division of the deformation fractal dimension of the Sanzhou xi landslide is carried out . First , according to the GPS monitoring data of each monitoring point of the surface displacement of the Sanzhou xi landslide , the surface displacement locus curve of the monitoring point is analyzed and collated ;
secondly , taking the fluctuation of the whole year and the reservoir as a calculation period , and segmenting the displacement locus of each monitoring point ;
then , performing image processing and conversion on the displacement locus curve after the segmentation of each monitoring point to obtain a grayscale image of each motion track segment curve ;
then , calculating the fractal dimension of each gray scale image by using the box model ;
Finally , the fractal dimension zoning map of each periodic stage of landslide deformation is obtained by the inverse distance interpolation method ( IDW ) .

( 8 ) Based on the calculation of the whole damage probability of the GeoStudio landslide , the fractal dimension zoning map of the landslide deformation , the geological environmental characteristics of the landslide development and the investigation data of the macroscopic deformation of the landslide site , the probability of the local damage of the landslide is selected .
The risk on the right side of the landslide is larger than that of the left side ;
As a whole , the risk of landslide during the decline of reservoir level is higher than that of reservoir water level ;
At the same time , the relation between the region and the ground crack spreading position in the two working conditions of the decline of the water level of the reservoir and the rising of the reservoir water level can be speculated that the cracks in the vertical main sliding direction may be the result of the local deformation and cracking of the landslide under the combined action of the elevation of the reservoir , and the cracks developed in the parallel main sliding direction by the vertical main sliding direction are more likely to be the result of the local deformation of the landslide during the decline of the reservoir water level .

( 9 ) The risk analysis of the landslide is carried out on the basis of the landslide bearing body and its economic value and population distribution data . According to the fluctuation period of water level fluctuation , the paper discusses the risk of Sanzhou xi landslide . The main consideration is that the landslide risk is higher than that of reservoir water level .
For the economic value risk of buildings in the area of the landslide , the risk of the reservoir water level decrease is generally higher than that of the reservoir water level . During the decline of the reservoir level , the economic value risk of the building is 0.28 to RMB 100 million , while in the rise period of the reservoir level , the risk of the economic value of the house building is 0.16 to 280 million yuan ;
For indoor population risk in the area of landslide , the population risk of some houses is higher than that of reservoir water level during the decline of reservoir water level . During the rising period of reservoir water level , the indoor population risk is 4 in the range of landslide , and the decline period of reservoir water level is 8 persons ;
In addition , for the value risk of other agricultural and weed land , the risk of land economic value at different parts of the landslide is 933 - 160yuan / mu , and the risk of land economic value at different parts of the landslide is 107 - 933 yuan / mu .

【学位授予单位】：中国地质大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：P642.22;TV221.2

【参考文献】