On the Behavior of Pressured Underground Pipe with Rehabilitated by CIPP

臺灣早期石化工業蓬勃發展，石化工業在民生工業之中扮演著相當重要的角色，與人民的生活息息相關，而近年來台灣因為管線老舊所引發的工安事件頻傳，其發生的原因多半是對於管線生命週期及修繕的專業知識嚴重缺乏，老舊的石化管線需要修繕或是替換，來預防因管線損壞而衍生出的汙染或是工安問題，但是在大都市中由於交通以及地下管線錯綜複雜，使用傳統明挖覆蓋工法更換新管顯得相對困難，而近年來，免開挖現場內襯更生工法(cured-in-place-pipe)，已開始被拿來應用於地下管線的更生作業。在前人CIPP內襯更生工法的研究中，考慮內襯與管材之間介面性質的研究相當有限，因此本研究進行更生內襯與管材間介面性質的物理實驗，來得到兩者間的介面性質，並且建立數值模型探討管材表面出現凹陷破損的情形，以小尺度實驗直線管模型來驗證數值模型是否符合真實情形，再以驗證過之模式進行相關大尺度之實際案例分析，其中包含直線管與曲線彎管之分析討論。 本文分為三大部分，第一部分為內襯與管材間介面性質實驗，本研究根據規範設計實驗夾具，進行正向及切向介面性質實驗，來求得介面性質之參數；第二部分為管材加內壓之小尺度物理模型實驗及數值模擬，於管材局部破損凹陷旁設置應變計，埋設在物理模型砂箱中，即模擬管材局部凹陷在覆土與地表載重下施加內壓力之應變情況，並建立與物理模型實驗相同尺寸之數值模型，在模型之管材上移除部分網格元素產生與物理實驗管材相等大小圓形凹陷，模擬覆土與地表載重下隨管內壓力改變之應變情形，隨後與物理實驗結果進行比較討論；第三部分為利用介面性質實驗所獲得之介面參數，依照實際工程的管材尺寸及覆土深度與相關材料參數建立不同案例之數值模型討論，以直線管與曲線管彎分別對管材尺寸、凹陷破損的位置、地表載重、內襯材料以及介面性質之強弱，分別探討管材更生前後之行為。 本研究之主要發現有：1.本研究設計之介面性質實驗，確實可以用來取得介面性質之相關參數2.於物理實驗與數值分析比較後，證實了數值模型在管材凹陷旁應變的趨勢符合實驗結果3.在小尺度模型中，覆土中管材在地表載重大於管內壓力時，管材凹陷處周圍的應變皆為負值。在凹陷面積增大時，隨氣壓增大之橫向應變變化得更加劇烈，縱向應變變化則趨於平緩4.地下老舊管線使用內襯之修復效果與內襯楊氏係數之高低有關，內襯楊氏係數越高就越能有效的降低管材凹陷處之應力及位移變化5.在相同尺寸下的彎管對於內襯楊氏係數的需求高於直線管，需要較高楊氏係數之內襯材料更生材管材凹陷處應力變化才有明顯減緩6.在內襯材料過於軟弱之情況，即使給予相當高強度之介面性質，也無法提升內襯修復的效果，若內襯楊氏係數提升至能達到有效降低管材凹陷處應力變化的情況，此時增加管材與內襯間的介面性質便可更進一步的提升內襯更生修復的效果。The petrochemical industry flourished in Taiwan area for the past four dacades. In recent years, the underground pipeline accidents were mostly due to the fact that the life cycle and serious repair of petrochemical industry pipeline are lack of professional knowledge. The old petrochemical pipeline needs repair or replacement, but due to traffic and complex of underground pipelines, it is difficult to install new pipes by the traditional excavation method. In recent years, cured-in-place-pipe (CIPP) has been applied and becoming popular in the underground pipeline rehabilitation operations. For the research of CIPP method, the study of the interfacial properties between the lining and the pipe is still limited. Therefore, the experiment of the interface between the lining and the pipe is carried out in this study, Then the numerical model is established to explore the case where the surface of the pipe is damaged.The experimental model of small diameter is used to verify whether the numerical model conforms to the real situation. And then the large diameter cases, including straight-line and curved cases, were analyzed and discussed. This paper is divided into three parts. The first part is the experiments for the interface properties. According to the standards, this study designs the gripping components for the normal and shear tests of the interface, to obtain interface parameters through the experiments. The second part is the physical model of pipe with internal pressure. The strain gage is set up in the local damage of the pipe. It is embedded in the physical model sand box, that is, the local depression of the simulated pipe is applied under the cover and surface load. The numerical model of the same size as that of the physical model experiment is established, and some of the grid elements are removed from the pipe of the model to produce the same size and circular thickness as the physical experimental pipe. Pressure change of the strain situation, followed by physical experiments to compare the results discussed. The third part is the analysis of large diameter cases, using the interface parameters obtained by the interface experiments, According to the pipe diameter, depth, and material parameters, different cases were numerically analyzed and discussed. Both straight-line and curved cases with different pipe diameter, location of the damaged, surface load, lining material and interface property, respectively, were analyzed to explore the behavior of the pipe before and after rehabilitated. The main findings of this study include:1. The designs of interface experiment were performed and can be applied to obtain interface properties. 2.For the physical model of small diameter pipe, when the pipe load in the casing is larger than the pressure in the pipe, the surrounding strain is negative. In the depression area increases, with the increase in the pressure of the lateral strain changes more intense, the longitudinal strain changes tend to be gentle 3. The effect of the CIPP rehabilitation on of the pipeline is related to the Young's modulus of the lining, the higher the Young's modulus is the more effective on the reduction of the stress and displacement in the pipe. 5. For the same diameter curved pipe, the requirement of the Young's modulus of lining is higher than that of the straight-line pipe; the stress changes in the depressions of the corroded pipe with higher Young's modulus lining are significantly reduced. 6. For the case of lining material is too weak, even with a higher strength interface, it can not provide a effectiver of rehabilitation. If the lining of the Young's modulus increases to be able to effectively reduce the stress at the depression of the pipe changes, then increasing the strength of interface can further enhances the performance of rehabilitation.目錄 vi 表目錄 x 圖目錄 xi 照片目錄 xiv 第一章 緒論 1 1.1.前言 1 1.2.研究動機與目的 1 1.3.研究方法與內容 2 1.4.論文架構 2 第二章 文獻回顧 5 2.1.管材受外力之力學行為 5 2.2.管材鏽蝕與受力行為相關文獻 7 2.3.現地內襯固化工法(cured-in-place-pipe) 8 2.4.管線工程之數值模擬 10 第三章 物理模型實驗 14 3.1.模型相似性 14 3.2.管內加壓實驗設備 15 1.大型砂箱 15 2.砂漏桶 15 3.微型應變計及資料擷取系統 16 4.實驗用管材 16 5.金剛鑽銼刀 16 6.加壓系統 17 3.3.管材加內壓模型作業流程 17 3.3.1.管材表面凹陷區製作作業 17 3.3.2.應變計設置作業 18 3.3.3.無覆土下管材加內壓作業 18 3.3.4.覆土下管材加內壓作業 18 第四章 數值模擬 31 4.1.數值分析方法 31 4.1.1.有限元素法 31 4.1.2.有限元素法之優點 31 4.2.分析軟體 32 4.2.1.ABAQUS介紹 32 4.2.2.ABAQUS在岩土工程中的適用性 33 4.2.3.ABAQUS分析步驟 34 4.3.數值模型理論基礎 35 4.3.1.數值模擬基本假設 35 4.3.2.數值分析理論基礎 35 4.3.3.現地應力狀況 36 4.4.數值模型之建立 37 4.4.1.小尺寸模型之幾何條件與邊界條件 38 4.4.2.模型網格劃分與元素選用 39 4.5.接觸模式分析 41 4.5.1.接觸對(contact pair)之設定 41 4.5.2.土壤與管材之介面性質 42 4.5.3.數值分析之膠合介面性質參數 43 4.6.小尺寸模型之材料類型與塑性準則選用 45 第五章 小尺寸模型驗證與行為分析 54 5.1.無覆土管內加壓行為 54 5.2.覆土下管內加壓行為 55 5.2.1.管材大尺寸表面凹陷 55 5.2.2.不同尺寸表面凹陷比較 56 5.3.小結與討論 57 第六章 更生內襯與管線之介面性質 72 6.1.實驗設備 72 6.1.1.實驗用管材試片 72 6.1.2.自來水更生用內襯材料 72 6.1.3.自來水更生用環氧樹脂 72 6.1.4.高黏性環氧樹脂 73 6.1.5.實驗儀器與夾具 73 6.2.單面搭接剪切實驗(single lap shear test) 73 6.2.1.試體製作流程 73 6.2.2.單面搭接剪切實驗(single lap shear test)作業 74 6.3.正向拉伸實驗(Tensile Test) 75 6.3.1.試體製作流程 75 6.3.2.正向拉伸實驗(Tensile Test)作業 75 6.4.管材與內襯材料介面性質實驗結果 76 6.4.1.單面搭接剪切實驗(single lap shear test)結果 76 6.4.2.正向拉伸實驗(Tensile Test)結果 77 第七章 現地模型之案例分析 87 7.1.案例之現地模型 87 7.1.1管徑尺寸及覆土深度 87 7.1.2.現地模型之幾何條件與邊界條件 87 7.1.3.現地模型之材料類型與塑性準則選用 88 7.1.4.介面性質 88 7.1.5.內襯材料尺寸與材料性質 89 7.1.6.管內壓力及地表載重 89 7.2.案例參數分析 90 7.2.1.管材幾何形狀及凹陷位置之討論 90 7.2.2.地表載重之討論 92 7.2.3.彎管內襯材料及介面性質強度之討論 93 7.2.4.直管與彎管內襯材料及介面性質強度之比較 94 7.3.小結與討論 95 第八章 結論 116 參考文獻 11