Research On Landslide Hazard Assessment And Harmful Assessment In Benzilan Reservoir Area Along The Jinsha River

Water is the most important material on the world, and it also is one of the mostimportant materials for all human and life on earth to survive. China’s water resourcesare extremely rich, but because the rainfall distribution is very uneven in time andspace, thus causing water resources is very unevenly distributed in time and space. InYunnan Province, the spatial distribution feature of water resources is that: waterresources decrease from south to north and from west to east and from valley to plain.This causes that the central region of Yunnan was short of water resources and lack ofcity water and agricultural drought. Population and industry focus in this region. Sothe water diversion project for central region came into being, but Benzilan reservoiris located in Hengduan Mountains area. Tectonic movement and earthquake areactive,and folds, faults, joints are fractured, the river cut deeper and alternating wetand dry climate, weathering intense in this area. And these cause geological disastersoccurrence frequently.In this paper, the author takes landslides and sediments in Benzilan reservoir areaas the research object, uses the3S technology, and uses the software MapGIS toestablish a three-dimensional digital visualization model based on the satellite remotesensing images of reservoir and topographic map. Then the results of the indoorremote sensing image interpretation were analyzes and thus used to assist thelandslide site surveys in the region, so as to obtain detailed characteristic parametersof landslides and sediments. At last, a comprehensive survey method for large-scalegeological disaster was established.28landslides and sediments developed in the region were detailed surveyed, thelandslide’s spatial development characteristics was analyzed: the characteristics is thatmainly landslides were distributed in the reservoir head and central region. Themainly landslides mechanisms were bend–rip failure.From three aspects, such as the landslide geological environment, characteristicparameters and dominant factors, the factors related to landslides hazard wereextracted. And10factors of landslide hazard assessment were determined by correlation test. The subjective weight was calculated by weighted lease squaremethod, and the objective weight was calculated by entropy method, the combinationweight were determined based on distance function at last. Landslide hazardassessment model was established based on the unascertained measurement theory,then the danger level was judged by confidence recognition criterion. The results ofassessment and the preliminary determination results on field agree well.The landslide hazard assessment results was used to evaluate the landslideharmful assessment, while distance from dam site, sliding distance, swell height,population in landslide risk areas, distance away from roads and land resource typewere selected for landslide harmful assessment. The evaluation results indicate thatthe majority of landslides in the reservoir were in mild and moderate harmful level,the minority is in extremely hazardous level and severe harmful level.