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1、<p><b>  附錄Ⅰ:翻譯原文</b></p><p>  Modeling of an obstacle detection sensor for horizontal directional drilling (HDD) operations</p><p>  A.P. Jaganathan a, J.N. Shah a, E.N. Allouc

2、he a,?, M. Kieba b, C.J. Ziolkowski b</p><p>  Keywords: Look-ahead;Numerical modeling;Differential impedance;Obstacle detection;Horizontal directional drilling</p><p>  Abstract: Horizontal Dir

3、ectional Drilling (HDD) is a commonly used construction method for the installation of underground pipelines, conduits and cables in urban areas and across obstacles such as rivers, railways and highways. A key concern i

4、n using the HDD method is the risk of hitting existing buried utilities during the pilotboring operation, which could potentiallly result in significant economic losses, disruption of services and injuries and/or loss of

5、 life. The Differential Impedance Ob</p><p>  Introduction</p><p>  Beneath the US landscape lie a vast network of buried utilities and pipelines, stretching for nearly 10.6million miles, which

6、include natural gas lines, power lines, water distribution and collection systems and optical-fiber communication lines [1]. The need for laying new utilities to support newtechnologies (i.e., the ‘lastmile’ program), co

7、upled with increasing dem ands of an ever growing population, has resulted in a highly congested underground space, particularly in urban areas. A paralle</p><p>  Current practices for avoiding physical dam

8、age during HDD operations include search of GIS based databases (i.e., One Call system in U.S) to identify existing buried utilities within the project boundaries and surface surveys using geophysical tools such as cable

9、 locators, ground penetrating radar (GPR) and other locating methods. However, in some cases the One Cal l system is not fully effective due to inaccurate (or non-existing) records, cluttered environment (e.g., utilities

10、 that are stacked</p><p>  Fig. 1. Utility hits (cross-bore) resulting from HDD installations</p><p>  A literature review of current and emerging ‘look-ahead’ technology development efforts is

11、presented. Thereafter, a description of the Differential Impedance Obstacle Detection DIOD system developed by the Gas Technology Institute (GTI) in collaboration with the Trenchless Technology Center (TTC) is provided.

12、The DIOD system induces a low frequency electric fie ld within the soil medium surrounding the drill head. The obstacle is detected by measuring changes in impedance occurring due to distor</p><p>  Current

13、and emerging borehole technologies for obstacle detection</p><p>  To avoid a utility strike, HDD operators have to detect buried utilities before a physical contact between the drill head and the utility ta

14、kes place. In recent years several efforts have been made to develop sensor technology that could be incorporated into the HDD drill head with the capablity of detecting both, metallic and nonmetallic obstacles in near r

15、eal-time.</p><p>  Nakauchiet al. [8] developed a small ground-penetrating radar system that is incorporated within a HDD drill head. It consists of a pair of antennas located at the cutting edge of th e dri

16、ll head and protected by a ceramic cover, a signal generator, a receiver and a communication link for transfering data gathered to the ground surface. The principle of operation behind this technology is similar to that

17、of a pulsed GPR, where an electromagnetic signal with duration of 0.6 ns is transmitted ahea</p><p>  California Energy Commission (CEC) [10] reported the development of a multisensory platform named SafeNav

18、? for HDD operations. The SafeNav system has been coupled with the AccuNav? guidance system, used for establishing the location of the drill head [11]. Safe Nav and AccuNavwork in conjunction to detect underground obstac

19、les, and also to communic ate the information gathered by the various sensory systems to the surface [12]. The system consists of 25 sensors including two sets of magnetometer</p><p>  SoniPulse Inc. has dev

20、eloped a seismic based obstacle detection system for HDD. It employs an array of geophones located on the ground surface above the HDD path for detecting the seismic signals generated by the drill head [13]. The seismic

21、energy generated by the drill head is scattered by the buried obstacles along its path, and this scattered energy is recorded by geophones located 0.3 m apart. The geophones were coupled with the ground such that the sig

22、nal-to background noise ratio was mini</p><p>  Fig. 2. A HDD drill mounted with DIOD; original device (top) and the corresponding CAD model (bottom).</p><p>  Differential impedance obstacle de

23、tection (DIOD) sensor</p><p>  The operating principle of the DIOD sensor is based on the Wheat stone bridge circuit. When the sensor is buried within a homogeneous soil with no obstacles (e.g., metallic pip

24、e) in its vicinity, the bridge circuit is in a balanced state with the differential output between the sensing electrodes returning a null value. As the sensor approaches the obstacle, the impedance of the soil medium ch

25、anges, and as a result the bridge reaches an unbalanced state with differential voltage observed between</p><p>  Finite element modeling</p><p>  Numerical modeling of the DIOD sensor was carri

26、ed out using the commercially available finite element software COMSOL Multiphysics with AC/DC module [15]. Since the wavelengths of the electric signal used in DIOD are very large compared with the dimensions of the mod

27、eled structure, the problem was treated as static/quasi-static in nature [15]. Two separate numerical models were created using the electrostatic and quasi-static modes available in CO MSOL AC/DC module. The electrostati

28、c mode was us</p><p>  Fig. 3. 3-D mesh of the numerical model containing a HDD drill mounted with DIOD.</p><p>  A 3-D rendering of the numerical model (approximately 220,000 interior elements

29、and 19,500 exterior elements) is shown in Fig. 3. The cutting edge of the drill was assigned a value of +30 V and the sleeve was assigned a value of ?30 V, similar to the actual system. The external boundary of the model

30、ed domain was assumed to be grounded as it was sufficiently distanced from the modeled device. The interfaces between the dielectric mediums were assigned ‘electrical continuity boundary’ condition. T</p><p>

31、;<b>  附錄Ⅱ:翻譯</b></p><p>  水平定向鉆機(jī)障礙檢測傳感器運(yùn)行建模</p><p>  A.P. Jaganathan a, J.N. Shah a, E.N. Allouche a,?, M. Kieba b, C.J. Ziolkowski</p><p>  關(guān)鍵詞:預(yù)見性;數(shù)值模擬;差分阻抗;障礙物探測;水平定向

32、鉆機(jī)</p><p>  摘要:水平定向鉆進(jìn)(HDD)是一種常用的安裝地下管道的施工方法,管道和電纜在城市地區(qū)和跨越障礙,如河流、鐵路和高速公路。使用HDD方法的一個關(guān)鍵問題是鉆孔過程中有破壞現(xiàn)有的公用設(shè)施造成生命威脅。差分阻抗的障礙檢測(二極管)是一種“預(yù)見性”傳感系統(tǒng),開發(fā)的目的是檢測金屬和熱塑性塑料管道在鏜頭的路徑。采用二極管傳感器數(shù)值模擬,并通過比較其預(yù)測模型進(jìn)行驗(yàn)證與實(shí)驗(yàn)測量物理原型在受控的環(huán)境中執(zhí)行。

33、驗(yàn)證后的模型中,參數(shù)研究能對二極管在實(shí)踐中可能遇到的各種情況進(jìn)行預(yù)測。</p><p><b>  引言</b></p><p>  美國景觀下埋著龐大的網(wǎng)絡(luò)工具和管道,綿延近10.6百萬英里,其中包括天然氣線,電源線,配水和收集系統(tǒng)和光纖通信線路。需要鋪設(shè)新的管道,以支持新技術(shù) (即“ 用戶距離 ”計劃) ,再加上不斷增長的人口的不斷增長的需求,導(dǎo)致了高度擁擠的地下

34、空間,特別是在城市地區(qū)。新的施工方法能最大限度地減少開挖,減少對交通的影響和建筑環(huán)境的利用率。水平定向鉆進(jìn)(HDD) ,一個非開挖方法安裝管道和地下管道的技術(shù),已成為近年來流行的施工方法,由于它的多功能性,成本效益和相對較小的施工破壞。使用HDD方法的主要問題是在枯燥的過程中錯誤操作造成危險的發(fā)生。它可能會破壞位于沿其軌道上的現(xiàn)有工具。這種操作錯誤可能會導(dǎo)致極大的經(jīng)濟(jì)損失(即損壞地下管道或建筑物導(dǎo)致服務(wù)中斷),以及受傷和死亡,過去十五年

35、來已經(jīng)報道過上千起由于操作失誤導(dǎo)致危險管道被破壞引起事故的案例,造成了一些嚴(yán)重的后果。應(yīng)用于HDD的損傷信息報告工具(DIRT ),由通用地面聯(lián)盟發(fā)起,僅2005年就在全國推廣。由于天然氣管線或者下水道橫切橫向連接的布置形式,在城市地區(qū)特別關(guān)注損傷信息報告,。這種情況的發(fā)生,通常稱為“交叉孔”,這種布置形式在施工過程中可能</p><p>  為避免HDD造成物理損壞目前的做法包括搜索基礎(chǔ)地理信息系統(tǒng)數(shù)據(jù)庫(即,

36、在美國一個電話系統(tǒng))利用地球物理工具,如電纜定位儀,探地雷達(dá),以確定項(xiàng)目邊界和表面調(diào)查,在現(xiàn)有的地下公用設(shè)施(GPR)和其他定位方法。然而,在某些情況下,一個電話系統(tǒng)由于不準(zhǔn)確的(或不存在)的記錄,雜亂的環(huán)境(例如,被垂直堆疊,或在水平方向上編織的實(shí)用程序),過度的環(huán)境噪聲(例如,架空電力線完全有效,鋼筋混凝土路面)和/或在當(dāng)?shù)氐牧⒎┒矗羌訅汗芫W(wǎng)從需要免除業(yè)主找到他們的資產(chǎn)提前建設(shè)項(xiàng)目。近年來做了很多嘗試,開發(fā)出“預(yù)讀”傳感器技術(shù),

37、可以在硬盤驅(qū)動器鉆頭內(nèi)運(yùn)行,以努力消除HDD造成破壞。</p><p>  圖1. HDD中的典型案例</p><p>  當(dāng)前新興的預(yù)測技術(shù)是在研發(fā)文獻(xiàn)回顧中提出的。此后,差分阻抗障礙物天然氣技術(shù)研究所( GTI)與非開挖技術(shù)中心(TTC )合作開發(fā)檢測( DIOD )系統(tǒng)的描述提供。該DIOD系統(tǒng)引起周圍鉆頭土壤介質(zhì)中低頻電場。所述障礙物是通過測量發(fā)生由于電場引起的障礙物的存在的失真變

38、化,阻抗檢測[7]。本文介紹了創(chuàng)建預(yù)測和優(yōu)化DIOD系統(tǒng)的性能進(jìn)行全面的三維數(shù)字模型的開發(fā)和驗(yàn)證。以下數(shù)值模型的實(shí)驗(yàn)驗(yàn)證,一個廣泛的參數(shù)研究的目的在于研究預(yù)計在實(shí)踐中遇到的各種條件,包括各種土壤類型,障礙物的不同方向就前進(jìn)的鉆頭,并根據(jù)不同的DIOD的表現(xiàn)管(或'障礙')的材料。</p><p>  當(dāng)前和新興的鉆孔障礙檢測技術(shù)</p><p>  為了避免公用事業(yè)遭到破壞

39、,HDD在鉆頭和工具接觸地下公用設(shè)施之前先檢測。近年來已經(jīng)開發(fā)出了一些傳感器技術(shù),可以納入HDD鉆機(jī)動力頭中以檢測金屬和非金屬障礙的能力。</p><p>  Nakauchi et al. 開發(fā)的是在一個HDD鉆頭中的小探地雷達(dá)系統(tǒng)。它由一對設(shè)在鉆頭的切削刃和陶瓷蓋組成,一個信號發(fā)生器,一個接收機(jī)和一個通信鏈路聚集到地面?zhèn)鬏敂?shù)據(jù)的保護(hù)天線。該技術(shù)的原理是類似脈沖GPR的,其中的電磁信號以0.6納秒的持續(xù)時間發(fā)送

40、領(lǐng)先于鉆頭和背散射電磁波被用于區(qū)分所述障礙物[8]。另一種基于探地雷達(dá)技術(shù),HDD報告了赫希[9]。這種特殊的雷達(dá)采用電磁波信號,25 MHz和500 MHz的頻率。赫希報道,證明了該傳感器是通過一個直徑100毫米的聚乙烯管道拉動原型設(shè)備進(jìn)行測試。</p><p>  加州能源委員會(CEC)[10]報道了一個名為安全導(dǎo)航?HDD運(yùn)作的多感官平臺的發(fā)展。安全導(dǎo)航系統(tǒng)已被加上準(zhǔn)確導(dǎo)航?引導(dǎo)系統(tǒng),用于確定所述鉆頭[1

41、1]的位置。安全導(dǎo)航,準(zhǔn)確導(dǎo)航協(xié)同工作,以探測地下障礙物,并且還要通過各種傳感系統(tǒng)收集信息傳達(dá)到表面[12] 。該系統(tǒng)由25個傳感器包括兩組磁強(qiáng)計,用于檢測埋地電力線,兩套三軸傳感器,用于跟蹤特定頻率的檢測通信線路的目的,地震檢波器,用于檢測聲信號,加速度計,用于跟蹤鉆頭頭部??的位置,并溫度傳感器,用于監(jiān)測常與HDD操作相關(guān)聯(lián)的苛刻工作條件下的電子設(shè)備的操作條件。該傳感器被設(shè)計成定位位于障礙物平行或垂直于鉆頭的軌跡前進(jìn)。該設(shè)計兼容最常

42、規(guī)的定向鉆井平臺。并且進(jìn)行了各種現(xiàn)場試驗(yàn)以對設(shè)計進(jìn)行改進(jìn)[12] 。</p><p>  SoniPulse公司已經(jīng)開發(fā)出了基于地震障礙物檢測系統(tǒng)的HDD。它采用設(shè)于地面上的HDD的路徑上,用于檢測由該鉆頭[13]產(chǎn)生的地震信號的地震檢波器的陣列。由鉆頭沿其路徑遭遇的障礙所產(chǎn)生的地震能量散射出去,而這散射能量被記錄由位于0.3米除了地震檢波器。地震檢波器分別加上接地,使得信號與背景噪聲比被最小化。高強(qiáng)度的聲音被連

43、續(xù)監(jiān)測,交叉相關(guān),并處理檢測到的峰的強(qiáng)度。如由鉆頭所產(chǎn)生的聲波太弱檢測低于一定的深度,一個噪聲發(fā)生器包括一個旋轉(zhuǎn)錘,其產(chǎn)生的特定聲音頻率加入到所述鉆頭組件。該技術(shù)已經(jīng)過測試,在5至10米,小直徑的管道在鉆頭2米距離的前方探測距離大口徑管道。</p><p>  圖2. 在HDD上安裝DIOD;原始設(shè)備(上)和相應(yīng)的CAD模型圖(下)</p><p>  差分阻抗障礙檢測傳感器</p&

44、gt;<p>  該DIOD傳感器的工作原理是基于小麥?zhǔn)瘶螂娐?。?dāng)傳感器被埋入均勻的土壤內(nèi),在其附近沒有障礙物(例如,金屬管),電橋電路在平衡狀態(tài)下與所述感測電極在返回一個空值之間差分輸出。作為傳感器接近障礙物,在土壤介質(zhì)的阻抗變化,并因此在橋到達(dá)一個不平衡的狀態(tài),其中每一對沿直徑放置感測電極之間觀察到的差分電壓。圖2示出的圖像原型DIOD傳感器集成在一個模擬的硬盤鉆頭以及感官系統(tǒng)的3維CAD渲染。原型鉆頭長900毫米直徑

45、63毫米。該鉆頭的切削刃(刃)用于將低頻( 50-500千赫)信號注入到地層中。正交放置圍繞該鉆頭的圓周上有4個電隔離的感應(yīng)銅電極,這是在與地面接觸電阻。在傳感器的早期版本中,銅電極,電容耦合與土壤(銅電極上覆蓋著一個外部塑料管和分別不與土壤直接接觸)。在較新版本的銅電極被重新設(shè)計為具有與所述土壤(與土壤直接接觸)的電阻耦合,以改善接觸電勢[14]。這一修改的實(shí)際意義是傾斜的寬度必須約等于鉆桿直徑。電位差保持在葉片和套管之間,從而使得電

46、場從葉片始發(fā)相交徑向放置銅電極之間的電壓差被放大并在濾波后進(jìn)行測定。在均勻介質(zhì)中的土壤,來自電極的輸出信號將通過該鉆桿前進(jìn)向前保持穩(wěn)定,但是,障礙的存在</p><p><b>  有限元建模</b></p><p>  該DIOD傳感器的數(shù)值模擬使用市售的有限元分析軟件COMSOL Multi physics軟件與AC / DC模塊[ 15 ] 進(jìn)行。由于與模型化的

47、結(jié)構(gòu)的尺寸相比,在DIOD使用的電信號的波長是非常大的,這個問題被視為靜態(tài)/準(zhǔn)靜態(tài)的性質(zhì)[15]。使用靜電和COMSOL AC / DC模塊可準(zhǔn)靜態(tài)模式下創(chuàng)建兩個單獨(dú)的數(shù)字模型。靜電方式用來預(yù)測傳感器的性能的同時,該鉆頭是在開放空間懸浮(即,周圍的空氣; ? = 1),而在準(zhǔn)靜態(tài)模式被用來在一個預(yù)測的傳感器的性能部分導(dǎo)電電介質(zhì)(即,在土壤形成) 。在使用準(zhǔn)靜態(tài)模式模擬中,對兩個獨(dú)立的案件進(jìn)行了模擬。在第一種情況下,忽略使用“準(zhǔn)靜態(tài)電流模

48、式'的磁場和電場之間的耦合進(jìn)行近似模擬。在第二種情況下,在電場和磁場之間的耦合利用“準(zhǔn)靜態(tài)電磁模式”模擬。</p><p>  數(shù)值模型(約220000內(nèi)飾元素和19500外部因素)的3-D渲染在圖3中表示出來。類似于實(shí)際系統(tǒng)的一個值,鉆頭的切削刃被分配+30 V,套筒的值被分配為-30伏。模型化結(jié)構(gòu)域的外部邊界被假定為接地,因?yàn)樗怀浞值貜哪M裝置隔開。介電介質(zhì)之間的接口被設(shè)置了“電氣連續(xù)性邊界'

49、;的條件。以便與各電極直接影響的所有其他電極隔離,接地的金屬圓柱體放置在特氟隆圓筒內(nèi)。在使用靜電模式進(jìn)行模擬,這四個電極被設(shè)置一個“浮動的潛在邊界”條件。在準(zhǔn)靜態(tài)電磁模式模擬運(yùn)行,外部界限通常用于建模導(dǎo)電薄膜[16]被認(rèn)為是磁絕緣和電極被設(shè)置“阻抗邊界“條件。在井孔的幾何形狀的基礎(chǔ)上,假設(shè)該土壤是在與鉆頭頭部??接觸進(jìn)行建模。</p><p>  圖3. 包含一個DIOD的HDD三維網(wǎng)格的數(shù)值模擬</p&g

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