本文選題：庫岸邊坡 + 多場　； 參考：《南京大學》2015年博士論文

【摘要】：國內(nèi)外水庫尤其是大型水庫工程中,受庫水位循環(huán)漲落影響而孕育和發(fā)生的庫岸新老滑坡,相比其他條件下的滑坡影響范圍更為廣泛,危害形式更加多樣化。庫岸邊坡監(jiān)測作為研究邊坡變形與失穩(wěn)破壞機理以及預(yù)防滑坡災(zāi)害的主要手段,對其技術(shù)的革新和研發(fā)以及據(jù)此開展的邊坡穩(wěn)定性研究,具有重要的理論和現(xiàn)實意義。從場的角度來看,庫岸邊坡是一個由基本場、滲流場、應(yīng)力場、溫度場、變形場等構(gòu)成的復(fù)雜多場系統(tǒng)。傳統(tǒng)的岸坡多場監(jiān)測技術(shù)與方法還存在諸多不足,難以達到岸坡多場信息獲取、分析與評價的要求。分布式光纖感測(Distributed Fiber. Optic Sensing,簡稱DFOS)技術(shù)突破了傳統(tǒng)點式感測技術(shù)的局限,可實現(xiàn)岸坡的連續(xù)分布式監(jiān)測,比較全面地獲得岸坡多場的變化信息,從而為岸坡的穩(wěn)定性評價和災(zāi)害預(yù)警提供基礎(chǔ)性資料。本文針對岸坡各場特點,圍繞三類分布式光纖感測技術(shù)—光纖布拉格光柵技術(shù)(FBG),布里淵光時域反射技術(shù)(BOTDR)和拉曼光時域反射技術(shù)(ROTDR),在室內(nèi)外試驗基礎(chǔ)上,比較系統(tǒng)地開展了庫岸邊坡多場監(jiān)測技術(shù)的研究；結(jié)合三峽庫區(qū)馬家溝邊坡,建立了岸坡分布式光纖感測系統(tǒng),已獲得了二年的監(jiān)測數(shù)據(jù)；在此基礎(chǔ)上,采用數(shù)據(jù)挖掘和數(shù)值模擬等方法,分析了岸坡演化過程中多場間的關(guān)聯(lián)性及其對邊坡穩(wěn)定性的影響；最后,采用突變理論,對岸坡的穩(wěn)定性及變形發(fā)展規(guī)律進行了評價。論文主要取得如下成果：(1)對三種基于布里淵散射光感測原理的BOTDR、BOTDA和BOFDA解調(diào)儀進行了對比試驗。測試結(jié)果表明：Neubrex公司生產(chǎn)的BOTDA要比fibrisTerre生產(chǎn)的BOFDA解調(diào)儀的空間分辨率要高,而測量重復(fù)性相近；二者的空間分辨率與測量重復(fù)性間呈反比關(guān)系,其乘積控制在±0.2MHz*m,折合±4με*m范圍以內(nèi)；BOTDA和BOFDA解調(diào)儀均需要感測光纖構(gòu)成回路,屬于雙端測量,適合于地質(zhì)工程結(jié)構(gòu)的精細化監(jiān)測,但對于復(fù)雜條件下的地質(zhì)體監(jiān)測存在較大的成活風險；而中國電科四十一所生產(chǎn)的BOTDR的空間分辨率和重復(fù)性雖然比BOTDA和BOFDA低,但單端測量的優(yōu)勢,十分適合于地質(zhì)體及地質(zhì)災(zāi)害的監(jiān)測。(2)開展了表面粘貼光纖應(yīng)變感測性能的試驗研究。當分布式光纖表面粘貼長度L15.8cm時,低傳感段長度可以控制在7cm以內(nèi),表明在工程應(yīng)用中,采用表面粘貼工藝時,光纖應(yīng)保證有足夠的粘貼長度,在采集應(yīng)變數(shù)據(jù)時,應(yīng)舍棄端部低傳感段誤差較大的數(shù)據(jù)。(3)理論推導(dǎo)了光纖測管式位移計的誤差計算公式,得出位移誤差與測試距離的平方成正比,與管徑成反比,并在試驗中得到了很好的印證。該公式還可適用于在其他梁式類結(jié)構(gòu)中進行位移分布式光纖監(jiān)測時的誤差分析。(4)設(shè)計并改進了基于DFOS技術(shù)的新型金屬基索狀應(yīng)變感測光纜,對課題組研發(fā)的基于FBG技術(shù)的溫度傳感器、滲壓計、液位計、鋼筋應(yīng)力計和土壓力計,開展了一系列試驗測試。設(shè)計出了庫岸邊坡多場光纖監(jiān)測方案,包括不同監(jiān)測場的DFOS技術(shù)及傳感器的選擇、感測光纜的布設(shè)方法、傳感器的安裝工藝、多場信息數(shù)據(jù)的表征、處理及分析。(5)建立了三峽庫區(qū)馬家溝邊坡多場光纖監(jiān)測系統(tǒng),成功獲得了岸坡二年的多場信息數(shù)據(jù),準確定位了邊坡深部滑動面和坡表滑動邊界,并定量得到了岸坡的位移變化規(guī)律。(6)結(jié)合基于Apriori算法的數(shù)據(jù)挖掘技術(shù),提取了多場信息的關(guān)聯(lián)規(guī)則,得到了三峽庫水位與馬家溝邊坡變形間的關(guān)聯(lián)性：整體而言,水位升高邊坡變形速率降低；水位處于低位時,邊坡變形速率增大。(7)建立了滲流場作用下馬家溝邊坡安全系數(shù)的數(shù)值計算模型。計算結(jié)果顯示,邊坡的安全系數(shù)與庫水位和庫水位變化速率有密切的關(guān)系。整體而言,高水位下邊坡的安全系數(shù)高,低水位下安全系數(shù)低；庫水位及其變化速率不同,邊坡的安全系數(shù)出現(xiàn)明顯的分區(qū)現(xiàn)象。當庫水位下降到150m水位附近時,安全系數(shù)最低；庫水位處于152～155m且變化速率在-0.45～0.26m/天時,安全系數(shù)出現(xiàn)快速降低。該計算結(jié)果也得到了邊坡變形監(jiān)測結(jié)果的印證。(8)引入了粒子群優(yōu)化算法,有效提高了邊坡非線性突變動力模型的反演精度。論證了邊坡滑面段測管位移與應(yīng)變作為狀態(tài)變量進行建模的等價性；建立了馬家溝邊坡變形發(fā)展的非線性動力學方程,并采用突變理論,分析得出馬家溝邊坡目前整體處在穩(wěn)定蠕變,尚未進入滑坡突變發(fā)展的階段。
[Abstract]:In comparison with other conditions , the reservoir slope is a complex multi - field system composed of basic field , seepage field , stress field , temperature field , deformation field and so on . Optic Sensing ( DFOS ) technology breaks through the limitation of traditional point sensing technology , and can realize continuous distributed monitoring of bank slope , so as to provide basic data for stability evaluation and disaster warning of bank slope .
The distributed optical fiber sensing system on bank slope has been established and two years of monitoring data have been obtained in combination with the Majigou slope in the Three Gorges Reservoir area .
Based on this , data mining and numerical simulation are used to analyze the correlation of multi - field and its influence on slope stability during the evolution of bank slope .
The results are as follows : ( 1 ) The results are as follows : ( 1 ) The results are as follows : ( 1 ) The results are as follows : ( 1 ) The results are as follows : ( 1 ) The results are as follows : ( 1 ) The results are as follows : ( 1 ) The results are as follows : ( 1 ) The spatial resolution of the BOFDA demodulator manufactured by Neubrex Company is higher than that of BOFDA demodulation instrument produced by Terre , and the measurement repeatability is similar ;
The spatial resolution of the two is inversely proportional to the measurement repeatability , and the product is controlled within 鹵 0.2 MHz * m and is within 鹵 4 渭蔚 * m range .
It is necessary to sense the optical fiber forming loop , which belongs to the double - end measurement , which is suitable for the fine monitoring of geological engineering structure , but has great survival risk for the monitoring of geological body under complex conditions .
In this paper , a series of tests have been carried out in this paper , which is based on the data mining technology based on the Apriori algorithm , and the relationship between the water level of the three gorges reservoir and the deformation of the Majigou slope is obtained .
The results show that the safety factor of the slope is high and the safety factor is low under the low water level .
The water level and its rate of change are different , and the safety factor of the slope has obvious zoning phenomenon . When the water level of reservoir falls to the water level of 150 m , the safety factor is the lowest ;
When the water level is 152 锝，

本文編號：1876076