應用三維數值模擬偵測廬山聚落大規模崩塌

Abstract

台灣由於特殊的地理位置，颱風、地震等自然現象頻繁。這些自然災害可能導致地滑、土石流和大規模崩塌，造成建物結構損壞和人員傷亡。大規模崩塌的發生往往會對該地區造成極大的災害，因此了解大規模崩塌的行爲非常重要。 本研究以廬山聚落為研究區，旨在利用三維數值模擬來確定大規模崩塌的範圍。本研究首先使用質點影像速度分析來辨識重大歷史災害事件引起的明顯地表位移。根據識別出的明顯地表位移區位，測試進行數值模擬所需要的邊界範圍。透過使用地下水位、流域劃設和流向，進行地下水位面的數值模擬，以獲得地下水位面資訊。將地下水位面資訊匯入模型中，對研究範圍進行數值模擬，以獲得大規模崩塌的行為。最後，將大規模崩塌的數值模擬結果與青山工程顧問（CGS，2020）估的結果以及PIV分析結果進行比對。通過由三種不同方法得出的結果對比，可獲得對研究區大規模崩塌行爲的瞭解。

Due to the unique geological location, natural disasters, such as typhoons and earthquakes, are common occurrences in Taiwan. These natural disasters may result in landslides, debris flows, and movements of deep-seated landslides. Especially deep-seated landslides, due to its scale, cause severe structural damage and human injury. Hence, it is important to increase the understanding regarding the deep-seated landslides. Using Lushan Settlement as the study area, this research aims to use 3-dimensional numerical simulation to identify the deep-seated landslide. This research would first use particle image velocimetry (PIV) analysis to identify the apparent ground movements caused by major historical events. Based on the identified segments that have apparent ground movements, the needed boundary extent for the numerical simulation will be tested. By using the groundwater level, watershed data, and flow direction, a groundwater surface numerical simulation was conducted to obtain the appropriate groundwater surface for the identified boundary extent. A mechanical numerical simulation for the identified boundary extent was then performed using the simulated groundwater surface. The result of the landslide numerical simulation was compared with the one estimated by Land Engineering Consultant (CGS, 2020) and also with the identified ground movement from the PIV analysis result. Thus, a comprehensive understanding regarding the deep-seated landslide behavior of the study area was achieved.