2018-08-012024-05-17https://scholars.lib.ntu.edu.tw/handle/123456789/675863摘要：國內早年物資缺乏，公路通過高陡岩坡多開鑿半隧道，形成許多倒懸邊坡，中等堅硬岩層中開挖坑道亦多未設置襯砌。此等通道屹立半世紀後，近年屢傳出岩楔滑動或是崩坍事件，甚至釀成災害。受限淨空或因景觀考量，大量的倒懸邊坡及無襯砌坑道不易全面加固。加之既有邊坡穩定及隧道變形分析法皆無法有效評估岩楔穩定性，形成安全通行以及坑道活化利用的風險。本計畫針對倒懸邊坡及無襯砌坑道的岩楔穩定課題，選擇已失穩以及潛在失穩等不同類型的代表性案例，現地調查露頭岩性及不連續面，結合近期迅速發展的測繪技術取得精細地形，應用赤平投影等運動學分析方法，於廣大範圍篩選潛在墜落岩塊並加以識別及標示；繼而透過精細地形描繪的潛在墜落岩塊幾何形狀，考慮其可能的運動及破壞型態，區分為可能移動岩楔以及敏感岩塊，選擇代表性岩楔及岩塊，依據不連續面幾何以及力學特性參數變異的影響程度，探討影響岩楔及岩塊穩定的重要因素；再者，針對可能移動岩楔及敏感岩塊的穩定評估課題，透過岩楔及岩塊3D幾何、相鄰不連續面幾何以及外接坡體或圍岩的變形或變位，發展數值模擬技術，提供不連續面幾何、力學特性參數以及坡體或圍岩變形等因素變異，對岩楔及岩塊穩定程度的量化至半量化影響分析工具。最後依據研究成果，提出倒懸邊坡及無襯砌坑道岩楔穩定評估指標，結合近期發展迅速的先進地面光達測繪技術，建議現地調查作業流程，以及相關的監測技術，預期可供工業界識別潛在墜落岩楔的失穩類型及運動方式，快速評估易致災路段位置，作為災害防治依據。<br> Abstract: In early days when goods are insufficient, highway pass through steep rock slopes with half tunnels, forming many overhanging slopes. Additionally, most tunnels in moderate hard rock masses were constructed without lining. After completed for over half a century, rock wedge sliding and collapse occurred in these passages, some has caused injuries. Considering the clearance limitation or the sightseeing demands, reinforcing all the entire overhanging slopes and unlined tunnels has its difficulties. Moreover, the existing analysis methods on slope stability and tunnel deformation cannot evaluate rock wedge stability adequately, the safe passing and passage revitalization is at stake. This research focuses on the rock wedge stability of overhanging slopes and unlined tunnels, and choses unstability or potential unstability slope as representative cases to investigate lithological characters and discontinuities of outcrop. Combining precision topography data obtained from mapping technology which developed quickly in this couple of years and using kinematic analysis method such as stereographic projection, potential falling rock mass can be identified and marked in a large-scale extent. After that, describing geometrical form of potential falling rock mass by precision topography, considering possible movement and failure type, separating susceptible rock mass from potential rock wedge and choosing representative rock mass or rock wedge, the important facts affected rock mass or rock wedge stability can be discussed by influence level of discontinuities geometrical and mechanical characteristic parameters. Furthermore, the issue of susceptible rock mass and potential rock wedge stability estimation can develop a numerical simulation technology as a quantification to semiquantification influence analysis tool of rock mass and rock wedge stability level, in order to provide geometrical and mechanical characteristic parameters of discontinuities and the deformation of slope mass or surrounding rock by the three dimension geometry of rock mass or rock wedge, geometry of adjacent discontinuities and deformation or displacement of slope mass or surrounding rock. Finally, the rock wedge stability estimation index of overhanging slopes and unlined tunnels will be advanced by the study result, and combined the advanced ground-based LiDAR mapping technology developed quickly in this couple of years to suggest a field investigation operational procedure and the related monitoring technology, and offered the industry to interpret the movement and failure type and estimate the site of vulnerability section quickly as the basis of disaster prevention.倒懸邊坡無襯砌坑道岩楔滑落穩定評估調查技術地面光達Overhanging slopeunlined tunnelwedge failurestability evaluation indexesinvestigation technologyground-based LiDAR