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Our country is a typhoon landing on the world largest one of the most serious national disaster, where Wenzhou is located in the southeast of China, history repeatedly the typhoon landing or serious impact on the region. Landing typhoons often triggered slope geological disasters such as landslides, avalanches, debris flow, so that the life and property of the people suffer serious losses, the impact of regional economic development. The The typhoon triggered Wenzhou slope geological disasters data collection, collation and on the basis of building a database (spatial database of geological disasters), from such geological hazards and their distribution characteristics, affecting factors start by mathematical statistics, spatial analysis, gray relational The analysis, theoretical analysis method reveals the development and distribution of such geological disasters in Wenzhou law, and the impact of factors, especially the typhoon effect of strong winds and heavy rain on the role of the slope and ramp the upwind load calculation is discussed. Slope geological disasters these findings for the typhoon triggered mechanism of typhoon zone slope stability studies provide the basis for future typhoon triggered slope geological disasters in China's southeast coastal areas of investigation, hazardous and risk assessment, as well as forecast and forecast disaster prevention and mitigation work to provide some guidance and reference. This article to 11 typhoons 2004-2009 example, collect a total of 286 such geological disasters, combined with the typhoon gale and rainstorm and moving path characteristics of major draw awareness and conclusions are as follows: the class geological disasters development to soil-type landslide ( collapse), the material component residual talus, the scale of less than 1000m3 main failure surface Quaternary overburden and the underlying bedrock contact interface and weak soil internal sliding surface-based. Geographical, geological disasters generally located in Wenzhou hilly area, an uneven distribution; single typhoon disaster distribution has obvious regional characteristics of the part was concentrated. Topography on the distribution of geological disasters in hilly areas and low mountain elevation 250 to 650m, gradient of 20 to 40 °, Aspect SE-SW direction, trees and other vegetation types, straight, stepped, convex sloping main . Formation lithology, the distribution of geological disasters pyroclastic rocks of the Jurassic strata and tuff, lava class lithology combination. Type of geological disasters, development and distribution typhoon moving path, wind range and heavy rain range is closely related to geological disasters is mostly limited to the path from the typhoon center within a vertical distance of 300km range, occurs mostly in the range of process Wind Speed ??Extreme - more than seven gale, some occur in the range of more than 10 gale, and the basic process of rainfall above 200mm or periods of rainfall occurred more than 100mm or the county where the average rainfall of more than 300mm (City) surface area; addition, the number and density of geological disasters and gale wind speed, rainfall intensity, The process of rainfall is not was simple positive correlation, mainly due to the combined effect of the geological environment conditions and many other factors also affected by. Class geological disasters most of the the typhoon landing - departure process gale and heavy rain roughly synchronized, no obvious hysteresis. The the basic geological disasters occurred before and after the typhoon landed 1d, the typhoon left the province before landing, more instability after the typhoon landed; gale Wenzhou maintain long before and after the typhoon landed, is conducive to the geological disasters; and basic occurrence rainfall during typhoon main places During heavy rainfall peak segment. By the method of gray correlation analysis of geological disasters in all affect the relationship between factors role in the extent and factors. Factors affecting the degree of sorting order of the wind speed, the duration of the natural slope, aspect, rock group structure, rainfall, vegetation, elevation, the airport surface slope angle and high winds. Which arbor slopes sort order of the wind speed, the natural slope of the rock group structure, aspect and rainfall, bamboo slopes order for wind speed, rainfall, rock group structure, aspect and natural slope, shrubs slopes order The rock group structure, wind speed, rainfall, aspect, and the natural slope of grasses slopes order for the natural slope of the rock group structure, aspect, wind speed and rainfall. The best correlation of typhoon wind speed arbor slope, wind speed, the greater the more likely to cause the type of slope occurs instability; bamboo slopes followed by wind speed may cause the class slope instability frequency reduced; shrubs, grass low class slopes. Correlation the typhoon area rainfall bamboo slopes better, increased broadly in line with the proportion of type of slope instability area rainfall increases, with trees, shrubs, grasses slopes followed; process rainfall arbor slope than good followed with bamboo, shrubs, grasses slopes. Trees and other class slopes typhoon gale of sensitivity is higher than the sensitivity of the typhoons and storms. Typhoon gale by acting directly on the slopes of rock and soil or rock and soil slope table indirect effects of vegetation on slopes to affect slope stability, different vegetation types slopes there are similarities and differences of the principles and effects of wind loads. Leeward slope increases below the leading edge position arbor trees for the the straight slopes roots arbor trees below the soil reaction force by downslope to the windward slope sliding force, and may result in the leading edge of a small part of soil instability; decline in force of the soil, may also lead to the instability of the small part of the soil. For root vegetation class slopes, windward slope vegetation can increase the the potential slip decline resistance the leeward slope vegetation can increase the thrust of potential slip decline. Vegetation on the slopes as the elastic bio-bar, tall trees, bamboo as a towering building the ramp as a dual-slope house, may be initially calculated by wind load size. In addition, the windward slope, the leeward slope and side slope tall vegetation wind vibration obvious role to play a larger impact on the slope stability. Typhoons and storms general rainstorm on the slopes of the mode of action and mechanisms, there is no essential difference. For bare slope, typhoons and storms effects enhance the role of the slopes; vegetation bunker slope, typhoons and storms role can be divided to its bare slope of the role and vegetation arising from the impact of the bare slope additional role of two parts, an additional role play to enhance or weaken the effect of different vegetation types slopes there are some differences. Meanwhile, the windward slope and leeward slope and side slope rainfall intensity vary caused by typhoons and storms strengthen or weaken the role.
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