三維多面體個別元素法在大規模崩塌模擬之研究

Simulation of the rock avalanches using 3D DEM with Polyhedrons

謝秉軒(Ping-Hsuan Hsieh) ； 吳建宏(Jian-Hong Wu)

《中華防災學刊》 12卷2期 (2020/09) Pp. 153-160

摘要

近年，大規模邊坡破壞發生頻繁，在破壞時往往在數十秒內伴隨大量的土石滑動，造成災害。本研究利用建構三維數值模型、切割不連續面來模擬現地地形與滑動塊體的堆疊，進而進行大規模崩塌數值模擬，探討其滑動歷程以及影響範圍，期能在未來有助於劃定大規模邊坡破壞潛勢區滑動影響範圍。本研究使用屬於個別元素法（Distinct Element Method, DEM）的Three-Dimensional Distinct Element Code（3DEC）軟體。模擬時透過給定重力以及改變不連續面摩擦角模擬塊體滑落。南勢坑地滑的模擬結果顯示該地區若發生滑動，將歷時大約30秒左右，在南勢坑溪中堆疊岩塊的影響長度可達390公尺，堆積高度則有30公尺。

關鍵字

大規模崩塌 ； 南勢坑 ； 數值模擬 ； 3DEC

並列摘要

Large-scale rock avalanche occurred frequently in recent years. Disasters result from the sliding of a large amount of sand/stone in tens of seconds. This study simulates the large-scale rock avalanche by numerical simulation to explore its sliding process and its impact area. Computational results determine the impact potential area in large-scale rock avalanche in the future. The Three-Dimensional Distinct Element Code (3DEC) belonging to the Distinct Element Method (DEM) was used in this study. During the simulation, gravitational force is the only external force to drive block movement with different frictional angles in the joints. The simulation results of the Nan-Shi-Keng sliding show that the slope failure will take about 30 s. The sliding rocks/soil will build a temporary dam with 390 m long and of 30 m height in the Nan-Shi-Keng River.

並列關鍵字

large-scale rock avalanche ； Nan-shi-keng ； numerical simulation ； 3DEC