三維地下水數值模式應用於卵礫石隧道開挖之模擬

The 3-D Groundwater Numerical Simulation of Seepage Phenomenon of Excavations around Gravel Tunnel

張德鑫(Te-Hsing Chang) ； 林旭信(Shiu-Shin Lin) ； 曾琮愷(Tsung-Kai Tseng)

《先進工程學刊》 5卷1期 (2010/01) Pp. 77-82

https://doi.org/10.29948/JAE.201001.0012

摘要

臺灣由於地形關係，重要都市發展與建設等大多位於西半部地區，而此區地層特性多屬沖積層或卵礫石堆積層，故許多工程需於紅土或礫石層中施工，因此卵礫石層對工程之影響爲重要課題。諸如隧道、邊坡、深開挖等基礎處理，地下水相關問題往往成爲工程成敗之關鍵，故施工中地下水處理爲重要工作，此舉可保障施工人員安全並避免造成施工時困擾。主要由於卵礫石層滲透係數高，地下水會使地盤強度降低，使開挖面無法自立，且易造成隧道內湧水，增加施工困難度。本研究之目的主要利用三維地下水數值模式，建立東西向快速道路漢寶－草屯線八卦山隧道開挖之卵礫石地層地下水數值模擬，藉由數值模式模擬隧道附近地下水流況，以評估隧道豎井開挖之深井降水措施之成效，模式亦可推估隧道開挖面滲流量，其模擬值與實際開挖之觀測量比較，以確認模擬結果可做爲後續類似工程評估之參考。

關鍵字

地下水 ； 數值模式 ； 礫石隧道

並列摘要

The tablelands and hills in the west of Taiwan are mostly composed of gravel. In quantity, however, researches on constructional property of gravel are much less than they on constructional property of rock and soil. Nowadays, the greater part of government-driven communication engineering is built through the gravel formation. The engineering characteristic and mechanical behavior of gravel consequently are a challenge to be dealt with. The destination of this study is to establish a 3D numerical model of the simulation site and apply this numerical model to groundwater simulations.
This study makes use of numerical model to analyze groundwater problems. According to the geological data and the hydrological information around the simulation site, the model is made up of the graphic display options of GMS. After construction of meshes, in order to make the model more similar to the actual situations of simulation site, it's necessary to find out the most appropriate material parameters. Only when they are selected, the 3D model could be used to carry the numerical simulation out. There are altogether two simulations in this study. One is the seepage condition of excavations around the tunnel and the other is the shaft excavations simulation. The result of this study might be an evaluating standard for the gravel tunnel excavations.

並列關鍵字

groundwater ； numerical model ； gravel tunnel