【作者】 倪至寬； 鄭文杰； 何明紳；

【Author】 Ni, Chin-Kuan 1 ,Cheng, Wen-Chieh 1 ,Ho, Ming-Shen 1 1 Taipei University of Technology (Taipei Tech),Taipei

【机构】 台北科技大學土木與防災研究所；

【摘要】 現今都會區地下運輸系統、地下大型電力管線與衛生下水道排水主管道施工大多採用潛盾工法施作,且以預鑄鋼筋混凝土環片作為襯砌材料。由於鋼筋混凝土環片的設計必須已知鋼筋與混凝土的應力歷史。但是,環片在製作過程包含蒸氣養生與水中養生,以及現場裝設時背填灌漿與二次灌漿,上述種種將導致環片鋼筋與混凝土的初始應力。如果初始應力無法得知,則環片之混凝土與鋼筋用量設計很難判定是否恰當或過於保守,易導致材料的浪費。為了檢討現行鋼筋混凝土設計是否過於保守,本研究利用結構及鋼筋混凝土力學理論發展一套數值分析模式,分別輸入鋼筋與混凝土的組合律,模擬在兩點反覆載重下梁結構中鋼筋與混凝土的應變與應力,比對梁結構中鋼筋的光纖感應器之量測值,檢核數值分析模式的正確性;其次,因光纖感測器價格過於昂貴,本研究嘗試在環片內埋置傳統振弦式鋼筋計量測鋼筋應變與應力歷史。試驗結果顯示傳統振弦式鋼筋計在蒸氣養生與水中養生過程可精確量測鋼筋應變,再利用鋼筋混凝環片在兩點反覆載重下所得鋼筋應變,與本研究發展的數值分析模式之載重-彎矩和載重-變形模擬結果相互比對有不錯的一致性,證實本數值分析模式之適用性。更多还原

【Abstract】 Metro-subway system, underground powder line and main sewer line are constructed by shield tunneling method in metropolitan area today. To properly design the reinforced concrete segment, the strain histories of rebar and concrete during the steam curing, water curing and back-grouting upon installation have to be known. If the initial stress or strain history is unknown, it would be difficult to evaluate the suitability of current segment design method. A numerical modeling based on the theoretical beam theory is developed in this study to analyze the rebar strains during cyclic loading on a beam embedded with optical fiber sensors. The numerical modeling results are compared with analytical solution for validation check of numerical modeling. Then a reinforced concrete segment instrumented with conventional vibrating wire strain gauges for its cheap price ismanufactured, cured, and tested under two-point cyclic loading. By comparing the numerical modeling results with experimental results, it concludes that the performance of vibrating wire strain gauge is as good as optical fiber sensor during steam and water curing,as well as in cyclic loading.更多还原