公路下側方開鑿隧道之護坡穩定研究-以汐止段山岳隧道工程為例

A Study on Slope Stabilization Protection for Highway Underpass Tunnel： Case Study on Hsichih Tunnel Project

鄒名堯(Ming-Yaung Tsou)

指導教授 ： 鄭光炎

國立臺北科技大學/工程學院/土木與防災研究所/碩士(2006年)

https://doi.org/10.6841/NTUT.2006.00173

摘要

台灣地形大部分為山地，在島上之交通深深受到山坡地阻隔影響極為不便利，所以打破山地區隔便為交通建設首要目標，而開鑿隧道又為最直接之動線。
洞口是隧道的起點，也是施工期間進出隧道的唯一通路，但往往隧道洞口受兩端既有路線限制，無法設在地形、地質最有利之處，而常常是在邊坡風化層或是崖錐堆積層處，地形、地質條件皆不利於開挖，因此洞口與邊坡之互制成為相當重要的課題，也不斷在考驗著工程人員的智慧與技術。
設置隧道洞口應僅可能減少對邊坡的開挖，邊坡過度開挖衍生之地工問題常超越隧道工程本身，是以先保護邊坡再開挖隧道的理念，是日後施築隧道洞口的最高指導原則。本論文列引過去因施作隧道洞口而致邊坡坍滑之數例，另再討論隧道施工本身所需注意之處及隧道與邊坡之間相互關係，並研析介紹在隧道施工期間並未對邊坡產生不良影響之成功案例，同時引介一種工法－「拱蓋工法」，經電腦模擬分析及現地實際施工和計測結果，格樑護坡、地錨和拱蓋之結合，確實可提供隧道開鑿期間鄰近邊坡穩當之保護與支撐。從而提供未來隧道工程在相似之地形、地質條件下，可靠引用之前例，並寄望未來可將此工法再加以延伸至更不利之地形、地質條件下模擬分析及參用。

關鍵字

邊坡 ； 隧道 ； 洞口 ； 坍滑 ； 拱蓋

並列摘要

Most land formations in Taiwan are mountain regions. Transportation in the isl- and is inconvenient because of mountainside obstructions; therefore, the demolitions of such hillside obstructions are usually the prime target of a transportation road construction,and chiseling of the tunnel is the most direct access.
The cavity is starting point of a tunnel and the only access during construction. In most cases, the cavity of a tunnel could not be established at the most favorable terrain and geological condition because of the limitation of existing roadways. It usually has to be located at weathered sloping area or sedimentary bank where both the terrain and geological conditions are unfavorable of excavation. Therefore, the mutual relationship between a cavity and its adjacent slope is the most essential subject, which has challenged the wisdom and skills of engineers.
The placing of a tunnel cavity should be arranged in a way to minimize the excavation of a slope as much as possible. The geo-technical problem resulted from excessive excavation of a slope usually surpasses the tunnel construction itself. The concept of “protect a slope before excavating a tunnel” is the utmost provisional principle of tunnel cavity construction.
This thesis is processed by taking several case studies of previous documented slope collapses because of tunnel cavity construction. Next to that, the thesis also discusses the essential awareness of the inter-relative aspects between a tunnel and its sloping area on building a tunnel cavity. Moreover, successful examples of projects that had managed to escape from the disadvantageous effect to the adjacent slope are also been analysis and introduced. Meanwhile, a construction method – “Invert Cover Construction Method” is also introduced. Through computer mock-up analysis and actual site construction against the calculation result, the combination of grating slope protection and earth anchor with the invert cover can actually provide the protection and support to the stability of adjacent slope during. With the aforementioned method statement, it can provide precedent samples to other projects that have similar terrains and geological conditions. Furthermore, it is highly potential to extend this construction method for computer mock-up analysis as the reference to projects on worse terrain and geological conditions.

並列關鍵字

Slope ； tunnel ； cavity ； collapse & slide ； invert cover

參考文獻

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