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1.
四川省都江堰市龙池地区泥石流危险性评价研究   总被引:1,自引:0,他引:1  
汶川地震灾区震后泥石流灾害较震前活跃,对灾区泥石流危险性进行评价是灾后重建过程中合理防灾减灾的基础工作。通过研究泥石流灾害事件中的泥石流规模、泥石流沟堆积扇面积及相应的灾害损失等基础资料,提出以泥石流在泥石流沟堆积扇上的平均堆积厚度替代泥石流规模作为主要危险因子的单沟泥石流危险性评价方法。用该方法对汶川震区都江堰市龙池镇龙溪河流域2010年"8.13"泥石流事件中的29条沟谷型泥石流进行危险性评价,评价结果中9条为高度危险,12条为中度危险,8条为低度危险。用以泥石流规模为主要危险因子的单沟泥石流危险性评价方法进行对比评价,2种评价方法中有65.5%的泥石流的危险性评价结果一致。以泥石流沟堆积扇平均堆积厚度为主要危险因子的单沟泥石流危险性评价方法更能突出规模对泥石流综合危险度的贡献,能更好地反映小泥石流流域和小泥石流堆积扇的泥石流在中小规模的泥石流总量下的危险程度。  相似文献   

2.
武都区北山泥石流灾害发育,对城区安全构成严重威胁。本文选取泥石流规模及发生频率作为主要因子,沟谷流域面积、主沟长度、流域相对高差、流域切割密度、泥沙补给长度比作为次要因子,采用理想点法对武都区北山7条泥石流沟进行了危险度评价。评价结果表明:研究区泥石流沟属低度危险-中度危险,与单沟泥石流危险度评价方法的结论基本吻合,符合实际情况,验证了该方法具有合理性及可靠性,为泥石流危险度评价提供了一种新的思路,同时也为研究区泥石流灾害的防治提供了科学依据和参考。  相似文献   

3.
甘肃省天水市罗玉沟泥石流灾害风险评价   总被引:2,自引:0,他引:2  
甘肃省天水市罗玉沟曾经爆发过多次泥石流灾害,造成了巨大的经济损失和环境破坏。文章引用单沟泥石流风险评价模型中危害度的计算方法,对罗玉沟流域可能发生泥石流的概率进行了评价;潜在的经济损失主要从人员社会、物质和资源环境3大类进行评价。泥石流风险评价结果显示,该小流域在100a的尺度内发生泥石流的可能性为80%。潜在的经济损失为379583万元。  相似文献   

4.
多宗隆哇泥石流沟位于青海省兴海县中铁乡,距茨哈峡水电站仅1km,流域面积为144.3km2,由于汇水面积大且物源较多,将对下游的茨哈峡电站造成威胁。运用泥石流风险评价理论,结合泥石流的危险度评价和易损度评价,综合多宗隆哇沟泥石流危险度评价(H单=0.50044)和灾害的易损度评价(V单=0.49),运用自然灾害风险度模型,得出了多宗隆哇沟泥石流的风险度为0.24,为中度风险泥石流沟。  相似文献   

5.
多宗隆哇泥石流沟位于青海省兴海县中铁乡,距茨哈峡水电站仅1km,流域面积为144.3km2,由于汇水面积大且物源较多,将对下游的茨哈峡电站造成威胁。运用泥石流风险评价理论,结合泥石流的危险度评价和易损度评价,综合多宗隆哇沟泥石流危险度评价(H单=0.50044)和灾害的易损度评价(V单=0.49),运用自然灾害风险度模型,得出了多宗隆哇沟泥石流的风险度为0.24,为中度风险泥石流沟。  相似文献   

6.
台风暴雨型泥石流单沟危险度研究   总被引:1,自引:1,他引:0       下载免费PDF全文
台风暴雨型泥石流分布广泛并常造成重大灾害,有必要对其危险度进行研究。选取温州山区的14处典型台风暴雨型泥石流为研究对象,构建了基于组合因子的单沟泥石流危险度评价模型。选取泥石流规模(M)、泥石流频率(F)、冲沟纵比降(J)、形成区完整系数(C)、台风降雨综合值(E)和地质综合因子(G)来表征泥石流危险程度,并基于信息熵理论获得各组合因子权重值。针对研究区均为低频泥石流的特点,引入麦尔登比率(R值)以间接确定基于不同R值范围的泥石流爆发频率(F)。将评价模型应用于所选的典型沟谷,得到各沟谷泥石流危险度,评价结果符合研究区泥石流沟谷为中、小型低频泥石流的实际情况,并且评价为危险度高的沟谷具备区域上最易形成泥石流的地质地貌条件。  相似文献   

7.
针对基于泥石流因子评价方法中选取因子不一及训练样本少的问题,提出了一种基于原型网络的沟谷泥石流灾害易发性评价方法。首先,通过元学习方式组织训练数据,计算每一类沟谷的原型中心。其次,计算未知样本与每一类原型中心的距离,得到其从属类别的概率。最后,根据类别概率计算沟谷的泥石流易发性指数,得到泥石流易发性评价等级。运用模型对怒江州的沟谷进行评价,并与历史灾害数据进行比对,分类正确率达到67.39%,历史事件中泥石流灾害严重程度与模型的评价等级吻合度较好。相比传统实地勘测和因子评价等方法,文章方法能够通过遥感影像进行泥石流灾害区域的快速识别与评价,为泥石流灾害的预警预测研究带来新的思路。  相似文献   

8.
薛喜成  朱清华 《地下水》2019,(3):97-99,150
近年来,由于极端天气事件频发和工程建设活动加剧,泥石流灾害对人类的威胁愈加严峻。因此,在综合分析泥石流灾害发育特征及形成机理的基础上,进行泥石流灾害易发性评价对防灾减灾工程活动具有指导意义。选取沟谷岸坡坡度、沟床纵坡比降、植被覆盖率、单位面积固体物源储量、汇水面积、雨季降雨量建立评价指标体系,采用熵权法确定评价指标权重,将泥石流灾害易发性分为高易发、中易发、低易发和不易发四级,建立基于正态云模型的泥石流灾害易发性评价方法,并以西秦岭地区5条泥石流沟为例验证了该评价模型的合理性。进一步将该模型用于陕西吴堡井沟泥石流灾害易发性评价,结果表明井沟泥石流具有中易发性,评价结果与实际相符。  相似文献   

9.
层次分析法在单沟泥石流危险度评价中的应用   总被引:28,自引:0,他引:28  
单沟泥石流危险度评价是泥石流危险性评价中的重要内容,对实现山区的安全减灾有着重要意义。文章从系统理论出发,运用层次分析法(AHP)对影响泥石流沟谷危险度的相关因子进行分析,构建单沟泥石流危险度评价的层次指标系统,并对各参与评价因子的权重作了计算,建立起单沟泥石流危险度评价模型。通过对泥石流沟的实例验证,评价结果与实际情况有较好的一致性。该方法将定量与定性相结合,能很好地解决泥石流危险度综合评价问题,对提高泥石流危险度评价的可靠性、准确性及客观性有一定的实践意义。  相似文献   

10.
针对洮河谷地(岷县段)所处的地质环境和条件的多样性、变异性、复杂性,泥石流沟谷从形成、发展至消亡受到了很多因素的影响,从而形成了这样一个较为复杂的泥石流灾害"模糊"巨系统,本文将模糊数学理论引入泥石流危险度的评价研究中。运用模糊综合评判法,参考国内刘希林、宫雪、陈伟等的相关文献,最后确定了沟谷纵比降、流域相对高差、泥沙沿程长度补给比、冲淤变幅、植被覆盖率等8个因素作为泥石流危险性评判因子,对岷县洮河流域21条泥石流沟做了单沟危险性评价。  相似文献   

11.
Dongchuan City is highly threatened by debris-flow disasters originating from Shengou gully, a typical debris-flow gully along Xiaojiang River in Yunnan Province (Kang et al. 2004). Shengou gully is studied, and a hazard assessment with numerical simulation is developed using ArcGIS 9.2 software. Debris-flow numerical simulation is an important method for predicting debris-flow inundation regions, zoning debris-flow risks, and helping in the design of debris-flow control works. Meanwhile, vulnerability measurement is essential for hazard and risk research. Based on the self-organized map neural network method, we combine the six vulnerability indicators to create an integrated debris-flow vulnerability map that depicts the vulnerability levels of Dongchuan City in Shengou Basin. Based on the risk assessment (including hazard assessment and vulnerability assessment), we adopt the principal–agent theory and use the risk degree of debris flows as an important index to build the insurance model and analyze the insurance premium of debris-flow disasters in Dongchuan City. This paper discusses the model and mechanism of property insurance in debris-flow risk regions and aims to provide technical support for insurance companies to participate in disaster prevention and reduction.  相似文献   

12.
An extended probabilistic model that is a modification of the Chen et al. (2007,) model for evaluating the failure probability of an inclined soil layer with an infinite length was developed in the present paper, and then applied to evaluate the occurrence probability of landslide-related debris flow in Tungmen gully located in the eastern Taiwan, which occurred a devastating debris flow in 1990. The statistical properties of hydrogeological parameters were collected and summarized, and then used to evaluate the landslide-related debris-flow probabilities at various relative water depths for Tungmen gully by using the probabilistic model. Under the assumption that the soil is saturated, the soil’s cohesion is negligible and the specific gravity of the solid particles of soils is a constant, a simplified probabilistic critical slope equation for the stability of an infinite slope of soils was also developed, and used to estimate the occurrence probability of debris flow. The result shows that probabilistic landslide analysis for an infinite slope could provide a suitable approximation for the risk analysis of debris flow mobilization at a given gully.  相似文献   

13.
2020年6月17日丹巴县梅龙沟爆发了一次大规模泥石流,一次性冲出固体物质42.7×104 m3,形成泥石流-堰塞坝-溃决洪水-滑坡灾害链,造成5100余户2.12万余人被迫转移,直接经济损失达8亿元。根据现场调查、无人机航拍以及遥感解译,分析梅龙沟泥石流的成因及致灾机理,阐述了“物源成因”、“降雨激发”和“地形促进”对泥石流形成产生的影响。结果表明:(1)梅龙沟泥石流是在前期累计降雨和短时强降雨共同作用下形成;(2)梅龙沟泥石流源头为大石堡沟,起动模式为“沟岸垮塌-泥石流”;(3)泥石流沟内持续的物源补给以及东风棚子、梅龙村、大邑村三处大型滑坡产生的级联堵溃效应,致使泥石流流量不断放大,最终导致大量固体物质冲出沟口;(4)沟口形成的堰塞坝-溃决洪水-阿娘寨滑坡灾害链进一步增强了泥石流的致灾能力;(5)现阶段梅龙沟内物源丰富,临界启动降雨阈值降低,极易在雨季发生大规模泥石流,建议及时采取综合防治措施。  相似文献   

14.
烧房沟滑坡型泥石流工程治理及效果分析   总被引:1,自引:0,他引:1  
国内对泥石流治理措施谷坊坝、格栅坝的作用和效果研究较多,而对滑坡型泥石流的综合治理措施和效果研究较少。2010.8.14强降雨过程导致汶川震区映秀镇烧房沟滑坡型泥石流暴发,通过分析其运动过程和现状沟道特征,结合滑坡堵点和沟道深切的特点,治理工程采用防堵防切综合工程结构形式:上游谷防群+中游抗滑桩、挡土板和肋板护脚护底+下游3座格栅坝+渡槽明洞跨越G213,并分析各分项工程作用:减弱龙头动能+控制LS01堵点、保护鞋尖+拦粗放细、顺畅排导。最后利用2010.8.14与2013.7.10的历史降雨量和固体参与量对比、工程治理前后动储量对比和各分项工程治理前后的沟道特点对比,验证了烧房沟滑坡型泥石流综合治理工程的效果良好。为今后震区滑坡型泥石流工程防治提供参考。  相似文献   

15.
Debris-flow phenomena in the Central Apennines of Italy   总被引:1,自引:0,他引:1  
The results of a research project on the extent of debris-flow processes in the Monti Sibillini area (Central Italy) are presented. Debris flows have greatly contributed in shaping the landscape of the Monti Sibillini territory. Based on the dominant active process they can be subdivided into three sections: a source area, a transport area and a depositional area. Four environments can be identified as source areas: landslide deposits, highly fractured rocks, scree or talus deposits, and glacial deposits. The evolution of some of the largest features present in the area is examined. These may have developed from an initial stage of mostly gully erosion and minor landsliding, through an intermediate stage characterized by extensive mass-movement, to a final stage dominated by fluvial processes. Lastly, generalizations on the debris-flow hazard in the study area are made.  相似文献   

16.
以北京市延庆地区南湾道豁子泥石流沟为研究对象,通过野外泥石流沟精细调查及历史资料统计,详细了解该泥石流发育特征和形成条件,针对流域内松散堆积物补给条件进行重点分析;综合研究该泥石流的动力学特征,进行泥石流危险区预测评价,提出相应的防治措施建议。研究结果表明:该泥石流沟内松散堆积物动储量为18.47×104 m3,分为冲洪积、残坡积、人工堆积和崩滑塌等4种补给来源,其中冲洪积和残坡积所占比重最大;泥石流发展阶段处于衰退期;经动力学分析,洪峰流量值在10年一遇的降雨条件下为52.53 m3/s,20年一遇的降雨条件下为59.25 m3/s,50年一遇的降雨条件下为68.13 m3/s,100年一遇的降雨条件下为74.85 m3/s,对应的一次固体冲出总量分别为0.77×104 m3、0.87×104 m3、1.00×104 m3和1.10×104 m3;属于中型泥石流,最大危险区面积为0.238 3 km2。通过评价分析,该泥石流沟仍存在爆发中型泥石流的可能性,将对下游南湾村以及千沙公路行车和行人的生命财产安全造成威胁。研究成果可为延庆地区该类泥石流单沟预警模型研究和灾害防治提供科学依据。  相似文献   

17.
文章通过对雅鲁藏布江的Ⅰ级支流—帕隆藏布江扎木镇-古乡段辫状水系地貌的研究,认为其与两岸支谷发育的泥石流群有关。通过对位于该河段下游的古乡沟和上游的地质弄巴泥石流特征的重点剖析,发现了特大型泥石流发育的2个重要特征,即支谷上游冰蚀围谷中赋存大量巨厚古今冰碛物和支谷中游峡谷段大型崩塌滑坡坝溃决。提出了特大型泥石流的成灾模式,并以该成灾模式解释了2000年易贡巨型滑坡堵江事件。最后,提出了基于上述成灾模式的帕隆藏布江流域特大型泥石流灾害防治的原则和方法。  相似文献   

18.
Landslides and debris flows occurr in China frequently and cause disastrous losses of life and property. The risk assessment of landslides and debris flows and their spatial variations were comparatively analyzed in this paper, which has great significance for disaster prevention. This article selected 1 km×1 km grid as the assessment unit and with support of GIS technique, analyzed landslide and debris-flow risk distribution and their spatial variations from 2000 to 2010. The research results indicated that the spatial distribution of risk classes in 2000 and 2010 was obviously discrepant. Overall, taking the Heihe-Tengchong population density line as the boundary, the west of the line is mainly low risk area; the east of the line is mainly high risk area. Compared with the risk of 2000, the risk values of 2010 increased, with the high risk area and low risk area enlarged, moderate risk area reduced. The moderate risk area is the most unstable and sensitive risk area, and its risk class variation is significant. However, China is not a region with the high risk of landslide and debris-flow hazard at present. In the following next 10 years, the risk of landslides and debris flows in China will continue to increase.  相似文献   

19.
On July 20, 2003, following a short duration of heavy rainfall, a debris-flow disaster occurred in the Minamata–Hougawachi area, Kumamoto Prefecture, Japan. This disaster was triggered by a landslide. In order to assess the landslide and debris-flow hazard potential of this mountainous region, the study of historic landslides is critical. The objective of the study is to couple 3D slope-stability analysis models and 2D numerical simulation of debris flow within a geographical information systems in order to identity the potential landslide-hazard area. Based on field observations, the failure mechanism of the past landslide is analyzed and the mechanical parameters for 3D slope-stability analysis are calculated from the historic landslide. Then, to locate potential new landslides, the studied area is divided into slope units. Based on 3D slope-stability analysis models and on Monte Carlo simulation, the spots of potential landslides are identified. Finally, we propose a depth-averaged 2D numerical model, in which the debris and water mixture is assumed to be a uniform continuous, incompressible, unsteady Newtonian fluid. The method accurately models the historic debris flow. According to the 2D numerical simulation, the results of the debris-flow model, including the potentially inundated areas, are analyzed, and potentially affected houses, river and road are mapped.  相似文献   

20.
This study investigates the variations in the critical conditions for debris-flow occurrence before and after the Chi-Chi earthquake in the Chen-Yu-Lan watershed, Taiwan. Topographical and rainfall parameters such as the gully gradient, drainage area, rainfall intensity, cumulative rainfall, and rainfall duration in the Chen-Yu-Lan watershed were used to analyze the conditions of debris-flow occurrence over the past 25 years. A recovery equation was proposed on the basis of rainfall parameters and used to determine the variations in the critical line of rainfall that trigger debris flow after the earthquake and to evaluate the recovery period required for the rainfall threshold of debris-flow occurrence after the earthquake to return to that before the earthquake in the watershed. The critical line for the runoff parameter versus gully gradient in the watershed was also presented.  相似文献   

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