Analysis of Potential Hazard on Nao-Liao Basin

• Main Authors: Hsin-Fu Tseng, 曾信富
• Other Authors: Kuang-Hsiang Chen
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/43078347645942484689

碩士 === 逢甲大學 === 土木工程所 === 99 === In order to mitigate the occurrence of disaster, reach the goals from the perspectives of homeland security and sustainable resource utilization, this research employed related map and information targeting to the characteristics and distribution of the potential landslides in Nao-Liao Basin. This research’s tool adopted the GIS (Geographic Information System) which calculated respective potential landslide indices such as slope, slope aspect, elevation, rock strength, rock mass structure and fault distance, etc, which were the relevant factors impacting landslide based upon the disaster occurrences. These would serve as the foundation for the catchment area classification and zoning for this basin. In addition, onsite field surveys as well as relevant formulae for the water and soil conservation technological rules were included to analyze potential landslide regions so as to supplement the insufficiencies which could have been derived from research. Research findings unveiled that the impact weightings for potential landslide factors were listed sequentially as follow: fault distance, slope, aspect, rock strength, height and type of rock structure. The high-potential landslide regions mostly scattered in the west and southwest. The rest of the regions like the north and east were intermediate-potential regions which tended to be sparsely distributed in addition to minimal amount of landslide found whereas the northeast and southeast were mostly regions with low-potential in landslide. At the mainstream and the upstream of A1 sub-catchment region, there were two major landslide locations found. The onsite survey and analysis for the major landslide at the sub-catchment region of the mainstream revealed that the north side of this region had the outcrop of rock layer and it should have approached stabilization stage whereas the south side was soil-based which tended to be unstable; therefore this spot should be strengthened with planting of vegetation as the primary means so as to alleviate the slope surface erosions. From the findings of onsite surveys, within the identifications and markings for the potential landslide region in the catchment area, it could only rely upon the coarse analysis from relevant map information for a portion of disaster sensitive regions. And this analysis could not take advantages presented from all the factors therefore it was pertinent to require onsite surveys and feedbacks from the records so as to comprehensively controlling the actual status at the catchment area and serving as the precursor for disaster prevention.