隧道襯砌變位與裂縫生衍分析模式暨結構異狀診斷平台開發

Analyzing Method for Lining Displacement and Associated Crack Growth and Diagnosis Platform for Tunnel Structural Anomalies

李奕辰(Yi-Chen Li)

指導教授 ： 王泰典

國立臺灣大學/工學院/土木工程學研究所/碩士(2019年)

https://doi.org/10.6342/NTU202002796

摘要

台灣的大多數隧道都是採用新奧工法建造，澆置混凝土作為二次襯砌，僅有美觀、整齊的功能，理論上建成後本身不會受力，但於隧道維護管理作業中常發現各類襯砌異狀，而襯砌異狀的出現說明隧道建成後仍然持續受到外力作用並導致隧道健全度受到影響，故判釋襯砌異狀可能的肇因，並釐清相關影響因素，是隧道維護管理作業中不可或缺的一環。
本研究研發診斷平台之目的在於整合同期不同襯砌異狀資料可以展示當時的隧道襯砌異狀、比較不同期資料間差異可有效地判釋裂縫變化，甚至預測未來襯砌持續變位引致裂縫可能生衍情況，並透過襯砌表面影像、裂縫描繪影像與數值隧道模型於三維空間內比對，對於隧道襯砌異狀的視覺化呈現有極大幫助。
本研究建立隧道襯砌變位與裂縫生衍模式，並採用連體與非連體耦合作為解析技術，裂縫的出現是指混凝土襯砌當前所承受應力超越其強度，採用非連體的優勢在於模擬裂縫發生、混凝土襯砌的峰後力學行為更準確，採用數值單壓試驗、多點抗彎試驗求其單壓強度、抗彎強度，並模擬於隧道中可能出現之受拉與受壓特性，透過實驗設計法進行混凝土材料之微觀參數率定，取得代表混凝土材料特性之微觀參數，隧道圍岩視為均質材料將採用連體分析。並以圓形隧道作為基本變位的驗證; 馬蹄形不含仰拱隧道則考慮不同期之微變位監測結果以進行案例模擬，藉此作為異狀肇因之診斷辦法。
襯砌結構異狀診斷平台結合三維數值隧道模型、襯砌異狀展開圖、數值模擬結果等，將有效地視覺化呈現襯砌裂縫分布與發展趨勢，並讓使用者對於三維空間中的襯砌異狀掌握度更高，對於分析混凝土襯砌受力狀態與裂縫發展有極大幫助，因應老舊隧道的安全補強措施，可視化的襯砌異狀結構診斷平台將有助於評估隧道的健全度。

關鍵字

結構異狀診斷平台 ； 三維視覺化 ； 連體非連體耦合 ； 襯砌變位 ； 裂縫生衍

並列摘要

Most of tunnels in Taiwan were built by the new Austrian tunnel method. The concrete is served as secondary lining. It has only beautiful and neat functions. In theory, it won’t be stressed after construction. However, various lining anomalies are often found in the past experience. The occurrence of the lining anomalies indicates that the tunnel would still be affected by external forces after the completion of the tunnel, which will affect the integrity of the tunnel. Thus, identifying the possible causes of linings anomalies and clarifying the relevant influencing factors are important to tunnel maintenance.
The diagnosis platform integrates the data acquiring from the same period to display the tunnel lining anomaly. And comparing the differences between data in different periods can effectively discriminate crack generation. It even predicts the possible propagation of cracks in the future. The comparison of the lining surface image, crack description image and 3D tunnel model are very helpful for the visualization of the tunnel lining anomalies.
This study establishes the tunnel lining displacement and crack generation analysis by adopting the FLAC PFC coupled method. The appearance of cracks means that the current stress on concrete lining exceeds its allowable strength. And through the experimental design method to calibrate the representative microparameters of concrete materials. In tunnel model, FLAC is used for the surrounding rock mass and PFC is used for concrete lining. The in-situ case simulation is based on the results of micro-displacement monitoring in different periods. FLAC PFC coupled method will be used as a diagnostic method for the causes of lining anomalies.
The lining structure abnormality diagnosis platform will effectively visualize the distribution and development trend of lining cracks. And let users have a better feeling of the lining anomalies in three-dimensional space. It is very helpful for analyzing the stress state of concrete lining and the crack propagation, and evaluating the integrity of tunnels.

並列關鍵字

diagnosis platform of lining anomaly ； FLAC PFC coupled method ； 3D visualization ； lining displacement ； crack propagation

參考文獻

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