知本溪上游堰塞湖之緊急調查與初步評估

堰塞湖多是因爲邊坡崩塌之土石阻礙河道所形成的，其規模大小與災害風險性會受集水區水文、河道地文與崩塌堆積土方影響甚巨。為瞭解其貯水量變化、溢流水量、土石壩滲流與穩定性及其對下游可能之影響，利用直昇飛機及無人載具空拍或衛星影像及遙測技術分析研判災害潛勢確有其必要性。本文以台東縣知本溪上游崩塌所形成之堰塞湖爲例，透過協調與團隊分工方式，在短時間內完成緊急調查與初步安全評估工作。經評估分析結果顯示邊坡崩塌的原因爲降雨及地震，而目前堰塞湖尚屬穩定，如果發生瞬間潰決狀況，對下游溫泉橋水位將有4公尺左右的影響，雖不至於有立即之危害，但仍建請河川管理單位加強下游地區的防範工作，並限制遊客民眾至溪床活動爲宜。

關鍵字

堰塞湖；崩塌；空拍；安全評估

並列摘要

Landslide lakes are mostly taking from the soil and stone that slope collapse hinder the river in Taiwan, between scale and disaster risk will very collect into the influence of watershed hydrology, physiography of water and piled up landslide sediment. In order to understand its amount of water stored changes, overflow water amount, earthdam seepage and possible stability influence to the downstream areas, coordinating the support of rescue helicopter and unmanned aerial vehicle to investigate and photograph or the applications of satellite image and remote sensing analysis technique for potential disaster's study and judgement will become more necessary. This cas study was taking Zhi-Ben river upstream landslide dam formed as a example in Taitung county, through coordinating the way of dividing the work with the group, finish urgent investigation and preliminary estimation the work of safely within short time. The analysis result shows the reason the slope landslide is rainfall and earthquake, and the earthdame is still steady on the landslide lake at present. If the Landslide lake breaking takes place in twinkling of an eye, there will be influence about 4 metres on the downstream water level at Wen-Guan bridge, although unlikely there is danger immediately, proposed the management goverment of river to strengthen the protection works of downstream embankment, and moved from the riverbed to limit the visitors people.

並列關鍵字

Landslide Dam ； Landslide Lake ； Aerial Photograph ； Stability Estimation

國際替代計量

知本溪上游堰塞湖之緊急調查與初步評估

全文下載

主題瀏覽