碩士 / 中華大學 / 營建管理研究所 / 93 / In accordance with the worldwide experiences of tunnel construction, the cutter discs (blades) mounted in shield tunneling machines are incapable of cutting reinforcing bars which is the fact that leads to the common heard inflow accidents occurred during the breaking work of either end of the curtain stoppers. It contains higher risk among the construction procedures. In the past, it had been constructed with traditional methods. Because the results of soil enhancement are largely affected by the site conditions such as soil conditions, construction methods and groundwater level, it is not an easy task to guarantee the result and safety.
The most dangerous part in shield tunneling is the curtain breaking at the arrival end. With insufficient carefulness, it is easy to result in mass seepage and land collapse. The traditional cement grouting method is not completely safe as well, especially on the soft seabed. To resolve the strong seepage and earth pressures during tunneling the area with high groundwater level, ground freezing which is used in the case of undersea tunnels has been investigated in this study. The history, development and the applicable situations of ground freezing are introduced by case study. The so-called ground freezing is to freeze the pore water and soil at the ends of the construction area into continuous frozen walls that provide high compressive strength and seepage resistance. After the tunnel structure is completed, the pore water and soil are then defrosted.
As the matter of fact that this method is rarely used in domestic tunnel construction and the magnitude of this engineering is unusually large in tunnel engineering. This special construction experience is able to offer great assistance on selection of design and construction method adopted in undersea and composite stratums. In addition, we hope it can provide a new viewpoint on renovation of construction technology for domestic tunnel engineering through the integration of in-site technologies and the combination of practical experiences. In this study, case studies are introduced to summarize the measures of ground freezing and point out the difficulties and obstacles during construction. Hopefully it is able to provide the civil engineering field a good reference and application for undersea tunnels.
| Identifer | oai:union.ndltd.org:TW/093CHPI0718041 |
| Date | January 2005 |
| Creators | Wang Jyh Kao, 王志高 |
| Contributors | 劉福勳 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 110 |
Page generated in 0.0125 seconds