山岳隧道施工監測與回饋設計 應用之探討

A Research on the Application of Monitoring Measurement and Back Analysis of Rock Tunnel

林志權(Chih-Chuan Lin)

指導教授 ： 王文生

國立臺北科技大學/工程學院/材料及資源工程系所/碩士(2006年)

https://doi.org/10.6841/NTUT.2006.00085

摘要

台灣是一個地質背景複雜的島嶼，由於地質條件的複雜性與岩體參數的變異性大，就算是透過再綿密的地質調查也難完全掌握地質狀況，故隧道設計過程中所援用之地質參數經常含有相當程度的不確定性。
鑑於精準的之地質參數與岩體力學參數取得不易，國內許多隧道的設計在安全重於經濟的考量下也相對偏保守，故若能落實隧道新奧工法邊作邊設計（design as you go）的理念，在施工中利用現地測得的計測資料，不斷的進行回饋分析與修正設計，才能真正達到即安全又經濟的施工品質。
惟國內隧道工程在傳統的發包體制不健全、營造廠商錯誤施工觀念與業主保守的技術官僚影響下，隧道施工監測通常只能輪為施工安全監測的一環，除非隧道在異常變位或面對緊急危難下，回饋分析與修正設計方能派上用場，至於偏保守的支撐設計，往往在業主、設計單位與施工廠商偏差的施工理念與缺乏信心下浪費了許多寶貴的材料與人力資源。
本研究係以國內正在施工中的隧道監測資料，依據反算分析法求取岩體參數，並擷取正算法與逆算法的優點，分段進行反算分析，完成支撐設計變更及施工，再以變更後之計測斷面實測變位量應證成果。以期日後對施工中隧道監測資料的回饋分析與設計建立一套可行且通用的標準作業流程。

關鍵字

回饋分析 ； 岩體參數 ； 反算分析 ； 正算法 ； 逆算法

並列摘要

Due to the complexity of geological situation and the variation of mechanical parameters of rock mass in Taiwan, inherent uncertainties are always existed in the choosing design parameters during tunnel design. It is real hard to know well about the geological situation before tunneling, even comprehensive geological investigations have been put in use.
Owing to the uncertainty on mechanical parameters, safety design is preferred for tunnel in Taiwan. Consequently, fulfilling the philosophy of New Australia Tunnel Method (NATM), design as you go, is of important for tunneling based on the monitoring system during construction. The measuring data related with deformation of tunnel surrounding rock, stresses and deformation of supporting system reflect the interaction behavior between tunnel and surrounding rock. Mechanical parameters which represent the tunnel behavior in practice can be approached through the skill of back analysis. And modification on excavation sequence and support system of original design can be conducted to fit the characteristic of tunnel surrounding rock. However, monitoring system has become part of safety control for tunnel construction in Taiwan because the conventional bidding system is unfavorable for design modification ,and the mind of engineer is conservative. Back analysis and feedback design are usually used for exceptional events such as huge deformation of surrounding rock.
This research establishes a systematic approach related with back analysis and feedback design. A characteristic curve for the deformation of tunnel surrounding rock is used to correct the initial deformation occurred before the installation of monitoring infrastructure. Back analysis is performed to figure out the representative mechanical parameters. Finally feedback design is carried out accordingly. The original design including excavation and supporting are discussed. The tunnel advancing rates of tunnel is enhanced form 60m to 90m monthly. Some topics concerned with back analysis and feedback design are also commented.

並列關鍵字

feedback design ； mechanical parameters of rock mass ； back analysis ； direct approach ； inverse approach

參考文獻

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