| China has a vast, complex and varied terrain, of which the mountainous area takes up about 2 / 3 or more. Mountain has a relatively complex geological structure, resulting in prone areas of geological hazards. With global climate change, the frequent extreme weather such as "continued heavy rainfall", "heavy rain" and "rain after continued drought," happened frequently, which induced geological disasters, giving rise to great difficulties in pass of mountain roads. Therefore, how to deal with effects of these geological disasters on mountain road traffic has become a problem to be solved desideratedly for the maintenance and unimpeded communication of mountain road. Based on this, the author believes that it is, under the current circumstances, an urgent need to perform a research, combined with practical engineering situation of mountain highways, on the risk assessment and zoning of geological hazards in main trunk roads, of which the purpose is to build a monitoring network used for road geological disasters and hence provide the basis work for taking emergency measures to protect life and property.This dissertation is supported by the western transportation construction projects, Three Gorges reservoir area of extreme weather derivatives highway disaster monitoring and early warning technology. Relying on the investitation materials from the research group author belonging to of Chongqing-related geological hazards in national and provincial trunk highway, the study explored a set of practical, geological disaster risk assessment theory and methodology, which is able to services in mountain highway projects and other large linear engineerings, and applied to risk assessment of geological hazards such as landslide and collapse occurred in national and provincial trunk highway in Chongqing. Through this study, obtained were the following results:?The national and provincial trunk highway in Chongqing as an example for field research of geological disasters mountain road, with a total length of 9346.84 research, catalog the historical point of 1695 disaster, potential disaster points 3283; on mountain road types and the development of geological hazards were identified failure modes that the landslide and collapse hazard is the main mountain road types of geological hazards, and its failure modes include progressive landslide debris flows, colluvium landslide, sandstone and mudstone, shale landslides and steep sandstone, mudstone, limestone cross layer collapse four categories. ?On mountain highway geologic hazard characterization of factors that gave birth to identify environmental geology, respectively, from topography, lithology, slope type, geological structure, hydrogeological conditions and vegetation cover aspects of the mountain road landslide, collapse of geological disasters, development law, Preliminary division and under the conditions of each single factor geological hazard level.?History and the distribution of potential disaster points to a certain extent affect the future development of geological disasters in mountain roads, this road geological disasters in Chongqing, for example, of the 249 national and provincial trunk roads of landslides, avalanches distribution of geological disasters in the number density and size from the density of two specialized research, obtained the corresponding distribution, and a preliminary classification.?Comprehensive use of various statistical analysis methods of the mountain highway geologic hazard associated with extreme rainfall. Mountain roads were fitted induced landslides, avalanches geological disasters formula cumulative effective rainfall and extreme rainfall events as the identification model and Logistic regression analysis was constructed through the mountain highway geologic hazard prediction model, and gives two kinds of models in the risk evaluation method.?Mountain highway geologic hazard risk evaluation is to investigate the geological evaluation of the region the degree of hazard. In this paper, the principle of risk assessment are described to determine the basic steps of risk assessment, and evaluation index system was constructed based on extension theory and fuzzy comprehensive evaluation model of integration method, and finally to national and provincial trunk highways Chongqing Geological Disaster risk assessment carried out as an example.?On the basis of previous studies to redefine the mountain road the vulnerability of geological disasters, the vulnerability used to describe a particular type of Disaster in disaster for the direct effects of damaged or destroyed, it is characterized disaster bodies and disasters The interaction between the degree of hazard-affected bodies is essentially destroyed when the intrinsic properties shown; the other hand, for a particular type of disaster, an indirect measure of the vulnerability of human society for the prevention and control measures taken by the disaster, set against disaster engineering effectiveness, prevention and control is passive and Disaster in the prevention and control of human society take the initiative to pay directly or indirectly involved in the synthesis. ?Mountain highway vulnerability assessment of geological hazards is different from the risk assessment, this paper observations on K-means clustering method on mountain roads the vulnerability of geological disasters have been studied by the level of vulnerability and use significant feature in Figure ARCGIS vulnerability was zoning.?Based on analysis of the complex system of geological disasters in mountain highways, the detailed risk management system of geological disasters in mountain highways was expatiated, the concept of risk line evaluation was proposed, the index system of line evaluation was constructed, and factors of the index system were definitively described. The comprehensive integratation approach was advised to be applied to risk assessment of geological disasters, the risk matrix figure was suggested to calculated and evaluate risk values of the various sections, and for solving the problem of poor intuitive application of risk matrix figure, the risk of ARCGIS was ultilized to zone vulnerability. |
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