本文關(guān)鍵詞： 長輸管道 腐蝕防護系統(tǒng) 動態(tài)評價方法 支持向量機 集對理論 權(quán)重計算方法　出處：《西安科技大學(xué)》2017年博士論文　論文類型：學(xué)位論文

【摘要】：長輸管道由于腐蝕引起的事故危害性特別嚴(yán)重,故針對管道腐蝕相關(guān)的安全管理和維護變得越來越重要。管道的腐蝕與防護是長輸管道完整性管理的核心組成部份,對其系統(tǒng)的安全性評價是實現(xiàn)管道完整性管理的基礎(chǔ)。目前國內(nèi)有關(guān)基于客觀數(shù)據(jù)分析和融合的管道腐蝕防護系統(tǒng)適用性綜合安全評價方法還處于起步階段。加之,系統(tǒng)的動態(tài)性特點,以及靜態(tài)評價方法的局限性,其相關(guān)的評價方法研究都具有相對主觀性較強,時效性、適應(yīng)性和有效性考慮不足等片面性的情況。因此、論文系統(tǒng)研究了運用客觀數(shù)據(jù)分析和融合為基礎(chǔ)的管道腐蝕防護系統(tǒng)安全性分級、綜合和動態(tài)評價方法及理論應(yīng)用,這對管道腐蝕防護系統(tǒng)的安全性評價及完整性管理的決策具有重要的理論和現(xiàn)實指導(dǎo)意義。通過對管道腐蝕類型分類,以及相關(guān)電化學(xué)腐蝕機理的分析,結(jié)合長輸管道常見腐蝕因素,建立了長輸管道腐蝕防護失效事故樹,為構(gòu)造長輸管道腐蝕防護系統(tǒng)評價指標(biāo)體系提供了依據(jù)標(biāo)準(zhǔn)。根據(jù)長輸管道外腐蝕突出的特點,結(jié)合現(xiàn)場測量、理化性質(zhì)和檢測數(shù)據(jù)分析,進行了土壤腐蝕、雜散電流腐蝕、陰極保護、防腐層保護的權(quán)重集研究,實現(xiàn)長輸管道的安全性分級和動態(tài)評價。對于土壤腐蝕評價,以往土壤腐蝕等級評價中不同方法所偏重的突出影響因素不同,對不同地域條件下方法的適應(yīng)性和有效性考慮不足,存在著評價的可靠性不高、時效性較差等問題。由于不同地域條件下土壤腐蝕多因素影響也不同的動態(tài)性特點,以及檢測數(shù)據(jù)存在冗余性、異常性,研究提出了粗糙集-決策樹-支持向量機(RS-DT-SVM)組合方法的土壤腐蝕等級動態(tài)評價。根據(jù)檢驗效果分析來看,RS-DT-SVM在多因素控制系統(tǒng)的評價等級分析中具有相對優(yōu)越性。對于雜散電流腐蝕評價,利用拉普拉斯方程建立雜散電流腐蝕狀態(tài)數(shù)學(xué)模型,并結(jié)合Comsol有限元軟件進行了數(shù)據(jù)仿真實驗研究,驗證了雜散電流與土壤電阻率成反比,與管地電勢之間成正比的關(guān)系,為雜散電流腐蝕強度評價提供了相應(yīng)的理論依據(jù)。結(jié)合國內(nèi)外相關(guān)標(biāo)準(zhǔn),給出了其與土壤電位梯度,管地位偏移的關(guān)系和評價指標(biāo)范圍。對于陰極保護評價,利用陰極保護準(zhǔn)則作為間接測量的方法進行了有效性的分析評價,提出了一種計算陰極保護系統(tǒng)平均IR降的判定方法,該方法比現(xiàn)有的測量平均IR降的方法簡單。利用此平均IR降加上各區(qū)段管道測試樁測量的通電電位,可估計管道實際通電電位是否符合陰保準(zhǔn)則,為管道陰極保護系統(tǒng)完整性管理及評價提供參考依據(jù)。對于防腐層保護評價,針對不同防腐層采用檢測方法不同。依據(jù)國內(nèi)外相關(guān)標(biāo)準(zhǔn)和準(zhǔn)則,得到了防腐層開挖和非開挖情況下的分級指標(biāo)體系和評價方法。針對靜態(tài)評價方法的不足研究了防腐層劣化趨勢的動態(tài)評價,構(gòu)建了一種集對(SPA)狀態(tài)評價和馬爾科夫鏈趨勢分析于一體的防腐層安全性動態(tài)評價方法。該方法通過檢測大數(shù)據(jù)的實例驗證,能對防腐層的安全水平進行動態(tài)評價,提高了防腐層劣化趨勢評價能力,為管道維護提供了決策性的理論依據(jù)。對于分級評價方法,為減少主觀因素,增加客觀因素分析的針對性,結(jié)合各指標(biāo)因素的特點,綜合利用實際客觀的檢測數(shù)據(jù),根據(jù)粗糙集和熵權(quán)計算法的應(yīng)用特點,將兩種方法組合進行權(quán)重的計算和驗證,提高了系統(tǒng)權(quán)重計算確定時的應(yīng)用性和可靠性。然后再利用集對理論聚類分析方法,根據(jù)各自指標(biāo)因素特征,建立具有針對性的聯(lián)系度應(yīng)用模型來進行分級評價,提高了分級評價的適用性,為評價指標(biāo)體系權(quán)重分析和分級評價提供指導(dǎo)。針對現(xiàn)有長輸管道綜合評價方法應(yīng)用有效性不足,適用性差的問題,提出利用集對理論多元聯(lián)系數(shù)的分析思想,將腐蝕和防護指標(biāo)體系與評價等級組成集對,并根據(jù)指標(biāo)特征建立有針對性的腐蝕態(tài)勢和防護態(tài)勢的四元聯(lián)系度關(guān)系式,從而可考慮到指標(biāo)之間的聯(lián)系,達到對管道的腐蝕態(tài)勢和防護性態(tài)勢兩方面聯(lián)系的綜合評價。該方法可反映出各管段的腐蝕和防護分級,找出重點的腐蝕防護區(qū)域,為綜合掌握管道腐蝕與防護態(tài)勢的危險等級提供了技術(shù)依據(jù),提高了長輸管道綜合評價的適用性和合理性。為了能合理描述系統(tǒng)動態(tài)性的特點,運用集對理論的集對勢進行了管道腐蝕與防護趨勢優(yōu)劣性的動態(tài)評價,提出了相關(guān)動態(tài)評價方法,發(fā)揮了綜合評價的意義,為管道腐蝕防護系統(tǒng)安全性評價提供了技術(shù)指導(dǎo)。采用實際現(xiàn)場檢測數(shù)據(jù),包括土壤腐蝕數(shù)據(jù)48組,管道腐蝕防護系統(tǒng)綜合數(shù)據(jù)6組,共計54組,通過2個一級指標(biāo)因素,4個二級指標(biāo)因素,20個三級指標(biāo)因素對上述各評價方法進行了驗證,其開挖結(jié)果表明各評價方法具有一定的實用性和有效性。應(yīng)用論文中的安全性評價方法,可根據(jù)實際環(huán)境的特點,動態(tài)的適應(yīng)性評價系統(tǒng)的安全性能,這對長輸管道腐蝕防護系統(tǒng)的安全性評價研究具有重要的現(xiàn)實意義。
[Abstract]:Long pipeline accidents caused due to corrosion damage is particularly serious, so the safety management for pipeline corrosion related and maintenance becomes more and more important. The corrosion and protection of pipeline is the core of pipeline integrity management part, to evaluate the safety of the system is based on the implementation of pipeline integrity management at home and abroad on. The objective data analysis system of corrosion protection and fusion pipeline applicable comprehensive safety evaluation method is still in the initial stage. Based on the coupled with the system dynamic characteristic, and the limitations of the static evaluation method, the evaluation methods of research have relatively strong subjectivity, timeliness, lack of adaptability and effectiveness of one-sided consideration. Therefore, this dissertation has systematically studied the use of objective data analysis and fusion based pipeline corrosion safety protection system of classification, comprehensive and dynamic evaluation method The theory and application, has important theoretical and practical significance of the pipeline corrosion protection system safety assessment and integrity management decision. Through the classification of pipeline corrosion types, and analysis of electrochemical corrosion mechanism, combining with the common corrosion factors of pipeline, a failure fault tree of pipeline corrosion protection, provide the standard for constructing the evaluation index system of long distance pipeline corrosion protection system. According to the characteristics of pipeline corrosion prominent, combined with field measurement, analysis of properties and test data, the soil corrosion, stray current corrosion, cathodic protection, corrosion protection layer set of weights, realize the safety classification of long distance the pipeline and dynamic evaluation for soil corrosion factors, to highlight the impact of different methods of soil corrosion grade evaluation on different conditions of the domain under different methods Lack of adaptability and effectiveness, there are the evaluation of reliability is not high, the problem of poor timeliness. The dynamic characteristic of soil corrosion factors due to different geographical conditions have different effects, redundancy, and detection of abnormal data, the research proposed the rough set and decision tree support vector machine (RS-DT-SVM) evaluation of soil corrosivity dynamic combination method. According to the test result analysis, RS-DT-SVM has the relative superiority in the evaluation level of multi factor analysis of control system. The evaluation for stray current corrosion, stray current corrosion using the mathematical model established the Laplasse equation, and the simulation experiment data combined with Comsol finite element software, verify the stray the current and the soil resistivity is inversely proportional to the relationship between pipe and ground potential is proportional to the corresponding theory, provides for the stray current corrosion strength evaluation On the basis of. Combined with relevant standards at home and abroad, and gives the soil potential gradient, pipe position offset relationship and range of evaluation index. Evaluation for cathodic protection, using cathodic protection standards as the indirect measurement method of effectiveness evaluation, put forward a calculation of the average IR cathodic protection system drop determination method, method the method is better than the existing IR measuring the average drop. By using this simple average IR with each section of pipe testing on potential pile measurement, can be estimated through the electric potential is consistent with the actual pipeline cathodic protection criteria for cathodic protection system of pipeline integrity management and provide reference for evaluation. Evaluation of anticorrosion coatings. In view of the different coatings using different detection methods. Based on the domestic and foreign relevant standards and norms, the anticorrosion layer excavation and non hierarchical index system and evaluation method under the condition of excavation in the static. Dynamic evaluation evaluation method to study the state of lack of coating deterioration trend, construct a set of (SPA) coating safety dynamic evaluation method of condition evaluation and trend analysis of Markov chain in one. The detection method by examples of big data validation, can dynamically evaluate the safety level of the anticorrosion layer, improve the corrosion evaluation of deterioration trend, the theoretical basis for decision-making for pipeline maintenance. The classification evaluation method, to reduce the subjective factors and objective factors for analysis, combined with the characteristics of each index, the detection data of actual objective comprehensive utilization, application characteristics calculation method based on rough set theory and entropy the two methods combined calculation and verification of weight, improve system reliability and weight calculation application determined. Then the set theory of cluster analysis method, according to their respective Factors of characteristics, to establish a connection for the application of the model for grade evaluation, improve the applicability of classification evaluation, provide guidance for the evaluation of the evaluation index system of weights analysis and classification. In view of the existing comprehensive evaluation method of long distance pipeline application effectiveness, the problem of poor applicability, the analysis thought of set theory multi contact number, the corrosion and protection of the index system and the evaluation grade set of components, and according to the characteristics of the establishment of the index of the corrosion situation and protection situation of four yuan of relation, which can take into account the link between indicators, comprehensive evaluation of two aspects to the corrosion situation of the pipeline and the protection of the contact situation. This method can reflect the pipe corrosion and protection grade, find the key regional corrosion protection, comprehensive grasp the dangerous situation of pipeline corrosion and protection grade of the offer The technical basis, improve the comprehensive evaluation of long distance pipeline and the applicability and rationality. In order to reasonably describe the characteristics of the dynamic system, the use of Set Pair Theory in the dynamic evaluation of pipeline corrosion and protection trends of potential advantages and disadvantages, puts forward relevant dynamic evaluation method, comprehensive evaluation of the significance of play, provided technical guidance for pipeline corrosion protection system safety evaluation. The testing data of the actual scene, including the soil corrosion data of 48 groups, pipeline corrosion protection system of comprehensive data of 6 groups, a total of 54 groups, the 2 level indicators, 4 level two indexes, 20 level three indexes to verify the various factors the evaluation method, the excavation results show that the evaluation method is practical and effective. The safety evaluation methods applied in this thesis, according to the characteristics of the actual environment, the dynamic adaptability evaluation system. It is of great practical significance to study the safety evaluation of long distance pipeline corrosion protection system.

【學(xué)位授予單位】：西安科技大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2017
【分類號】：TE988.2
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本文編號：1449287