tunnel

隧道
  • 文章类型: Journal Article
    随着我国交通网络的快速发展,比如川藏铁路,许多隧道正在建设或计划在山区。其中一些隧道必须穿越或位于活动断层带附近,这可能会受到断层滑动的损害。在这项研究中,利用断层-结构系统分两步分析了山岭隧道在同震断层作用下的地震反应。首先,提出了一种非均匀滑动模型来计算地质尺度上特定活动断层引起的地面变形和内部位移,考虑断层面上的非均匀滑移。选择1989年LomaPrieta和2022年门源地震作为案例研究,以验证所提出的滑移模型。其次,将门源地震的计算位移作为输入荷载,在工程规模上对大良隧道进行离散-连续耦合分析。大良隧道的模拟变形与门源地震后的现场破坏观测结果一致。最后,研究了不同断层条件对隧道地震反应的影响。结果表明,衬砌的峰值纵向应变的分布受断层机制的支配。断层滑动程度显著影响隧道的响应。穿过活动断层的隧道,具有较宽的断层断裂带和较小的倾角,其破坏较小。
    With the rapid development of Chinese transportation networks, such as the Sichuan-Tibet railway, numerous tunnels are under construction or planned in mountainous regions. Some of these tunnels must traverse or be situated near active fault zones, which could suffer damage from fault slip. In this study, the seismic response of a mountain tunnel subjected to coseismic faulting was analyzed using a fault-structure system in a two-step process. Firstly, a nonuniform slip model was proposed to calculate the ground deformations and internal displacements induced by a specific active fault on a geological scale, considering nonuniform slips on the fault plane. The 1989 Loma Prieta and 2022 Menyuan earthquakes were chosen as case studies to validate the proposed slip model. Secondly, the calculated displacement of the Menyuan earthquake was used as the input load for the discrete-continuous coupling analysis of the Daliang tunnel on an engineering scale. The simulated deformation of the Daliang tunnel aligned with the on-site damage observations following the Menyuan earthquake. Lastly, the effects of different fault conditions on the tunnel seismic response were investigated. The results indicate that the distribution of the peak longitudinal strain of the lining is governed by fault mechanisms, and the degree of fault slip significantly influences the response of the tunnel. A tunnel passing through an active fault with a wider fault fracture zone and smaller dip angle experience less damage.
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  • 文章类型: Journal Article
    目的:中隔穿孔(SP)是一个独特的挑战。有许多描述的手术方法具有可变的成功率。这项研究的目标是描述一种修复SP的新技术。
    方法:对18例前间隔穿孔患者进行了基于筛前动脉皮瓣(AEA)的“隧道技术”的内镜修复。人口统计数据,病因学,穿孔的大小,并收集成功率。
    结果:从2019年至2022年,招募了18例男性为主(67%)。平均穿孔尺寸为1.5cm(0.5-3.6cm)。完整的SP闭合成功率为94%(n=17/18),术后无并发症。随访7±5.2个月。
    结论:隧道技术AEA皮瓣重建与SP闭合的良好结果相关。隧道技术提供了一个有用的襟翼垫,并最大限度地减少了其他支持措施的使用。该技术为间隔穿孔修复提供了其他技术的补充。
    方法:第4级。
    OBJECTIVE: Septal perforations (SPs) present a distinct challenge. There are many described surgical approaches with variable success rates. The goal of this study is to describe a new technique in repairing SP.
    METHODS: A case series of eighteen patients with anterior septal perforation who underwent endoscopic repair with the \"tunnel technique\" based on anterior ethmoid artery flap (AEA) were analyzed. Demographic data, etiology, size of perforation, and success rate were collected.
    RESULTS: Eighteen cases with male predominance (67%) were enrolled from 2019 to 2022. The average perforation size was 1.5 cm (0.5- 3.6 cm). The success rate of complete SP closure was 94% (n = 17/18) with no complications after surgery. The patients were followed up for 7 ± 5.2 months.
    CONCLUSIONS: AEA flap reconstruction with the tunnel technique is associated with favorable outcomes in SP closure. The tunnel technique provides a useful flap bolster and minimizes the use of other supportive measures. This technique offers an addition to other techniques for septal perforation repair.
    METHODS: Level 4.
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  • 文章类型: Journal Article
    电缆芯和电缆套管的温度对于传输系统的安全性和效率至关重要。准确预测气体绝缘输电线路(GIL)隧道内输电温度场的分布和变化规律,是确保长GIL隧道输电系统安全稳定运行的关键。本文解决了在超长GIL输电隧道中计算非稳态传热流的挑战。本文提出了一个模型,和超长GIL传输传热流的快速求解方法。此外,分析了1000kVGIL运行过程中的温度变化。结果表明:随着运行时间的延长,导线和电缆套管温度逐渐升高,且趋于相对稳定。研究结果可为GIL隧道输电运行调控提供理论依据和数据支持。
    The temperature of the cable core and cable casing is crucial for the safety and efficiency of the transmission system. Accurately predicting the distribution and variation of the transmission temperature field in the gas insulated transmission lines (GIL) tunnel is essential to ensure the long GIL tunnel transmission system\'s safe and stable operation. This paper addresses the challenge of calculating unsteady heat transfer flow in extra-long GIL transmission tunnels. The paper proposes a model, and a rapid solution method for extra-long GIL transmission heat transfer flow. In addition, the temperature variation during the operation of 1000 kV GIL has been analyzed. The results indicated that the conductor and cable casing temperature gradually increases and tends to be relatively stable with the operation time. The research results can provide theoretical basis and data support for the regulation of GIL tunnel transmission operation.
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  • 文章类型: Journal Article
    尽管近年来在地理学领域取得了多项技术进步,使新的应用得以实现,并简化了合并的应用,一些任务仍然具有挑战性,低效,费时费力。这是狭窄空间的精确三维调查的情况。静态激光扫描是一种准确可靠的方法,但对于广泛的隧道环境是不切实际的;另一方面,便携式激光扫描是时间有效和高效的,但在没有地面控制约束的情况下不是很可靠。本文介绍了一种新颖的基于图像的多相机系统的开发过程,旨在解决这一特定问题:可靠,和有效的结果。从系统概念化和初步调查到设计选择和准确性要求,都说明了开发过程。所得到的工作原型已经进行了测试,以验证所提出的方法的有效性。
    Although the field of geomatics has seen multiple technological advances in recent years which enabled new applications and simplified the consolidated ones, some tasks remain challenging, inefficient, and time- and cost-consuming. This is the case of accurate tridimensional surveys of narrow spaces. Static laser scanning is an accurate and reliable approach but impractical for extensive tunnel environments; on the other hand, portable laser scanning is time-effective and efficient but not very reliable without ground control constraints. This paper describes the development process of a novel image-based multi-camera system meant to solve this specific problem: delivering accurate, reliable, and efficient results. The development is illustrated from the system conceptualization and initial investigations to the design choices and requirements for accuracy. The resulting working prototype has been put to the test to verify the effectiveness of the proposed approach.
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  • 文章类型: Journal Article
    目的:本研究旨在比较隧道式外周中心静脉置管(T-PICC)与成人癌症患者的常规PICC(C-PICC)。
    方法:一项多中心随机对照试验于2021年4月至2022年1月在中国7家医院进行。564名参与者被随机分配到T-PICC或C-PICC。收集并比较这些数据:基线特征和导管插入相关特征,围手术期并发症,和长期并发症。
    结果:553名参与者(年龄,52.6±12.3岁;女性,39.1%)进行最终分析。T-PICC组和C-PICC组患者围手术期并发症差异无统计学意义(均p>0.05)。与C-PICC相比,T-PICC可显著降低长期并发症的发生率(26.4%vs.39.9%,p<0.001)。具体来说,在中心线相关血流感染中发现并发症减少(1.8%vs.5.1%,p=0.04),血栓形成(1.1%vs.4.0%,p=0.03),导管移位(4.7%与10.1%,p=0.01),非传染性渗出(17.3%vs.28.6%,p=0.002),局部感染(3.6%vs.7.6%,p=0.04),皮肤刺激(6.1%vs.10.9%,p=0.046),并减少意外导管移除(2.2%vs.7.2%,p=0.005)。T-PICC和C-PICC在导管闭塞方面无显著差异(6.5%vs.5.8%,p=0.73)或皮肤损伤(2.2%vs.2.9%,p=0.58)。
    结论:T-PICC安全,可有效减少长期并发症。
    结论:隧道技术可有效减少PICC相关的长期并发症。因此,建议用于PICC相关并发症高风险的癌症患者.
    背景:https://www上的注册号。chictr.org.cn/是ChiCTR2100044632。试验注册中心的名称是“隧道与临床使用的多中心随机对照研究。非隧道式PICC“。
    结论:Cather相关并发症与导管插入技术有关。与常规PICC相比,隧道式PICC减少了导管相关的长期并发症。隧道式PICC放置为癌症患者提供了一种替代的导管插入方法。
    OBJECTIVE: This study aimed to compare the safety and effectiveness of tunneled peripherally inserted central catheters (T-PICC) vs. conventional PICCs (C-PICC) in adult cancer patients.
    METHODS: A multicentre randomized controlled trial was conducted between April 2021 and January 2022 in seven hospitals in China. 564 participants were randomly assigned to T-PICC or C-PICC. These data were collected and compared: the baseline characteristics and catheterization-related characteristics, periprocedural complications, and long-term complications.
    RESULTS: Five-hundred fifty-three participants (aged, 52.6 ± 12.3 years; female, 39.1%) were ultimately analyzed. No significant differences in periprocedural complications were found between the T-PICC and C-PICC groups (all p > 0.05). Compared with C-PICC, T-PICC significantly reduced the incidence of long-term complications (26.4% vs. 39.9%, p < 0.001). Specifically, reduced complications were found in central line-associated bloodstream infection (1.8% vs. 5.1%, p = 0.04), thrombosis (1.1% vs. 4.0%, p = 0.03), catheter dislodgement (4.7% vs. 10.1%, p = 0.01), non-infectious oozing (17.3% vs. 28.6%, p = 0.002), local infection (3.6% vs. 7.6%, p = 0.04), skin irritation (6.1% vs. 10.9%, p = 0.046), and reduced unplanned catheter removal (2.2% vs. 7.2%, p = 0.005). No significant differences were found between T-PICC and C-PICC regarding catheter occlusion (6.5% vs. 5.8%, p = 0.73) or skin damage (2.2% vs. 2.9%, p = 0.58).
    CONCLUSIONS: T-PICC is safe and effectively reduces long-term complications.
    CONCLUSIONS: The tunneled technique is effective in reducing PICC-related long-term complications. Thus, it is recommended for cancer patients at high risk of PICC-related complications.
    BACKGROUND: The registration number on https://www.chictr.org.cn/ is ChiCTR2100044632. The name of the trial registry is \"A multicenter randomized controlled study of clinical use of tunneled vs. non-tunneled PICC\".
    CONCLUSIONS: Cather-related complications are associated with the technique of catheterization. Compared with conventional PICC, tunneled PICC reduced catheter-related long-term complications. Tunneled PICC placement provides an alternative catheterization method for cancer patients.
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  • 文章类型: Journal Article
    在现有车站下修建隧道时,有必要控制他们的定居。现有车站有桩基时,桩路切割对既有站的沉降有显著影响。为确定既有桩对地铁车站沉降的影响,提出了合理的截桩时间。在成都地铁9号线下穿现有1号线孵化场站的基础上,通过数值模拟分析了隧道下穿既有1号线车站的沉降规律。此外,现有桩的变形和应力特性,管道屋顶,讨论了隧道衬砌和对既有车站的支护作用。结论是,现有桩的切割会引起隧道承载系统的变化,从而导致车站的一定变形。然后分析了不同截桩时间对既有站沉降的影响,明确了二次衬砌施工后隧道支护刚度显著增强。此时,显著降低了现有桩站的沉降。最后,通过实地调查,表面灌浆的效果,管棚,并确定了在现有桩基础存在时对现有车站的沉降控制的多层衬砌。该研究可为地下开挖隧道超小距离既有站的沉降控制和基础托换提供参考。
    In the construction of tunnels under existing stations, it is necessary to control their settlement. When there is a pile foundation in the existing station, the pile cutting has a significant impact on the settlement of the existing station. To determine the influence of existing piles on the settlement of subway stations, a reasonable pile-cutting time is proposed. Based on the Chengdu Metro Line 9 underpassing the existing Line 1 hatchery station, the settlement law of the tunnel underpassing the existing Line 1 station is analysed via a numerical simulation. Furthermore, the deformation and stress characteristics of the existing piles, pipe roofs, and tunnel linings and the supporting effect on the existing station are discussed. It is concluded that the cutting of existing piles causes a change in the tunnel bearing system, thus resulting in a certain deformation of the station. The influence of different pile cutting times on the settlement of the existing station is then analysed, and it is clarified that the tunnel support stiffness is significantly enhanced after the construction of the secondary lining. At this time, the settlement of the existing pile station is significantly reduced. Finally, through a field investigation, the effect of surface grouting, pipe shed, and multilayer lining on the settlement control of the existing station while the existing pile foundation exists is determined. This research can provide a reference for the settlement control and foundation underpinning of existing stations at ultra-small distances in underground excavation tunnels.
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  • 文章类型: Journal Article
    背景肝脏,作为身体最大的内脏器官,裂片显示出各种总体形态变化,可能具有临床意义的裂缝和过程。在各种解剖学变化中,发现最多的是肝圆韧带的变异裂隙。本研究是为了分类,review,比较和讨论有关肝圆韧带裂隙异常的文献。方法100例福尔马林保存的人肝脏从乔治国王医科大学解剖学系获得,勒克瑙,学习了一年。在我们的研究中,15%的肝脏显示出圆肝韧带裂隙的形态变化。这些被分为四种类型。在I型(2%)中,裂隙被肝桥改造成隧道。在II型(3%)中,肝圆韧带有一个不完整的裂隙,延伸到膈表面。在III型(4%)中,肝圆韧带仅在内脏表面出现不完整的裂隙。在IV型(6%)中,裂缝被薄膜覆盖。结论在这项对北印度人口的研究中,15%的肝脏有大体形态变异。因此,对肝脏上存在变异或异常表面特征的彻底解剖学知识对于理解放射科医生和外科医生的潜在病理学至关重要,以便可以实现有利的结果。
    Background The liver, being the largest internal organ of the body shows a variety of gross morphological variations about lobes, fissures and processes which may be clinically significant. Among various anatomical variations, the most found is the variant fissure for ligamentum teres hepatis. The present study was done to classify, review, compare and discuss the literature for anomalies in fissures for ligamentum teres hepatis. Methods A total of 100 formalin-preserved human livers were obtained from the Department of Anatomy of King George\'s Medical University, Lucknow, and studied for one year. Result In our study, 15% of the liver showed morphological variations in fissures for ligamentum teres hepatis. These were classified into four types. In type I (2%), the fissure was converted into a tunnel by pons hepatis. In type II (3%), there was an incomplete fissure for ligamentum teres hepatis extending into the diaphragmatic surface. In type III (4%), there was an incomplete fissure for ligamentum teres hepatis present only on the visceral surface. In type IV (6%), the fissure was covered by a thin membrane. Conclusion In this study of the North Indian population, 15% of liver have gross morphological variations. So thorough anatomical knowledge of the existence of variant or abnormal surface features on the liver is imperative to understanding the underlying pathology for radiologists and surgeons so that a favorable outcome can be achieved.
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  • 文章类型: Journal Article
    在隧道中生产堆肥的两种替代方法,从某些类别(猫。)3动物副产品(ABP)和其他非ABP材料,被评估。第一种方法建议最低温度为55°C,持续72小时,第二种方法为60°C,持续48小时,两者的最大粒径为200毫米。生物危害小组(BIOHAZ)的评估专门针对猫。3ABP材料(不再用于人类消费的餐饮废物和动物来源的加工食品)。评估了拟议的堆肥过程的功效,以减少至少5log10的粪肠球菌和沙门氏菌Senftenberg(775W,H2S阴性)和至少3log10的相关耐热病毒。申请人提供了可能进入堆肥过程的生物危害列表,并选择了细小病毒作为耐热病毒的指标。申请人提供的证据包括:(a)有关生物危害热灭活的文献资料;(b)关于减少粪肠球菌的验证研究的结果,沙门氏菌Senftenberg775WH2S阴性和犬细小病毒在欧洲堆肥植物中进行;(c)和使用两种替代方法的时间/温度条件直接测量堆肥材料中鼠细小病毒感染性降低的实验数据。提供的证据表明,拟议的替代方法可将粪肠球菌和沙门氏菌Senftenberg775WH2S阴性减少至少5log10,并将细小病毒减少至少3log10。BIOHAZ小组得出的结论是,正在评估的两种替代方法可以被视为等同于目前在欧盟委员会法规(EU)No142/2011中批准的处理方法。
    Two alternative methods for producing compost in a tunnel, from certain category (Cat.) 3 animal by-products (ABP) and other non-ABP material, were assessed. The first method proposed a minimum temperature of 55°C for 72 h and the second 60°C for 48 h, both with a maximum particle size of 200 mm. The assessment of the Panel on Biological Hazards (BIOHAZ) exclusively focused on Cat. 3 ABP materials (catering waste and processed foodstuffs of animal origin no longer intended for human consumption). The proposed composting processes were evaluated for their efficacy to achieve a reduction of at least 5 log10 of Enterococcus faecalis and Salmonella Senftenberg (775W, H2S negative) and at least 3 log10 of relevant thermoresistant viruses. The applicant provided a list of biological hazards that may enter the composting process and selected parvoviruses as the indicator of the thermoresistant viruses. The evidence provided by the applicant included: (a) literature data on thermal inactivation of biological hazards; (b) results from validation studies on the reduction of E. faecalis, Salmonella Senftenberg 775W H2S negative and canine parvovirus carried out in composting plants across Europe; (c) and experimental data from direct measurements of reduction of infectivity of murine parvovirus in compost material applying the time/temperature conditions of the two alternative methods. The evidence provided showed the capacity of the proposed alternative methods to reduce E. faecalis and Salmonella Senftenberg 775W H2S negative by at least 5 log10, and parvoviruses by at least 3 log10. The BIOHAZ Panel concluded that the two alternative methods under assessment can be considered to be equivalent to the processing method currently approved in the Commission Regulation (EU) No 142/2011.
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  • 文章类型: Journal Article
    最近在冲突地区发生的事件强调,成功发现和鉴定了埋藏的秘密综合体,掩体和隧道对全球法医调查人员至关重要,减少或解决犯罪活动,解决国家安全威胁,避免潜在的恐怖袭击。然而,这通常很难证明,特别是在城市地区,可能存在地下非目标物品和地上基础设施,这可能会干扰检测目标。在这里,我们提供了一些成功的案例研究,其中使用法医地球科学技术来检测和表征埋藏的秘密复合体,使用不同地球物理技术的掩体和隧道。一般来说,桌面研究评估预先存在的信息,包括当地的地质情况,土壤,历史/现代遥感,地图和照片告知适当的地球物理测量技术选择。然后采用随后的近地表地球物理技术来生成精确的地下目标计划,对地面基础设施的干扰影响进行数值建模和校正,使校准地球物理数据集,以提供信心,在各自的解释。所有的法医调查都是,当然,每个网站都是独一无二的,因此需要对各自的地面条件采取单独的方法。调查既要分阶段进行,又要反复进行,采用适合当地条件的技术:选择地球物理方法对于提高此类重要埋藏目标的成功率至关重要。
    Recent events in conflict zones have emphasized that the successful detection and characterisation of buried clandestine complexes, bunkers and tunnels is vitally important for forensic investigators globally, to reduce or solve criminal activities, address national security threats and avoid potential terrorist attacks. However, this can often prove very difficult, particularly in urban areas, with potentially both below-ground non target items and above-ground infrastructures present, that can interfere with detecting target(s). Here we provide selected successful case studies where forensic geoscience techniques were used to detect and characterise buried clandestine complexes, bunkers and tunnels using different geophysical techniques. Generally, desktop studies assessing pre-existing information, including local geology, soils, historical/modern remote sensing, maps and photographs inform appropriate geophysical survey technique(s) selection. Subsequent near-surface geophysical techniques are then employed to produce accurate plans of sub-surface targets, with numerical modelling and correction for the interfering effects of above ground infrastructure, enabling the calibration of geophysical datasets to provide confidence in their respective interpretations. All forensic investigations are, of course, unique to every site, and thus require an individual approach to their respective ground conditions. Investigations should be both phased and iterative, with techniques tailored to local conditions: the selection of geophysical method(s) is crucial to improve successful detection rates of such important buried targets.
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  • 文章类型: Journal Article
    在传统的隧道监测中,测量隧道内物体的特征点,获取物体的信息。考虑到传统方法在隧道复杂地表结构测量中的局限性,如有限的监测点,长的测量周期,精度低,这项研究介绍了一种使用三维(3D)激光扫描监测隧道横截面变形的方法。使用这种方法,以某高空超长隧道软弱围岩为监测对象。首先使用3D激光扫描仪扫描测试隧道,并对收集的数据进行了处理。随后将隧道的内部结构数据与实际轮廓线以及不同日期的主要分支和次要衬砌数据进行了比较。结果表明,当一次支管和二次衬砌位置在不同测点、桩号不同时,隧道拱顶在一定时间范围内趋于稳定。左右两侧桩数变形一般不超过0.02m,除了几个测量点。初始分支的实际截面与设计截面的比较表明,隧道初始分支的拱的实际高程大于其设计高程不超过0.3m。因此,通过这项研究,提出了一种方便实用的复杂曲线隧道结构变形监测方法。
    In traditional tunnel monitoring, the characteristic points of an object within a tunnel are measured to obtain information about the object. Considering the limitations of the traditional method in measuring the complex surface structure of tunnels, such as limited monitoring points, a long measurement period, and low precision, this study introduces an approach that uses three-dimensional (3D) laser scanning for monitoring tunnel cross-section deformation. Using this approach, the soft surrounding rock of a high-altitude ultralong tunnel was taken as the monitoring object. The test tunnel was first scanned using a 3D laser scanner, and the collected data were processed. The internal structural data of the tunnel were subsequently compared with its actual contour lines and the data of its primary branch and secondary lining on different dates. The results indicate that the arch roof of the tunnel tended to be stable within a certain time range when the positions of the primary branch and secondary lining were at different measuring points with different pile numbers. The deformation of the pile number on the left and right sides did not generally exceed 0.02 m, except at a few measuring points. A comparison between the actual cross section of the initial branch and that of the designed section showed that the actual elevation of the arch of the initial branch of the tunnel was greater than its designed elevation by no more than 0.3 m. Hence, through this study, a convenient and practical method is presented for monitoring deformation in complex curved tunnel structures.
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