Underground Space最新文献

Analysis of hydraulic breakdown and seepage of tail sealing system in shield tunnel machines 盾构隧道机尾部密封系统的液压破坏和渗流分析

IF 8.2 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2024-10-24 DOI: 10.1016/j.undsp.2024.08.003

Dalong Jin , Zhuoyu Li , Dajun Yuan , Yangyang Gan , Jian Chen , Haipeng Guo

The use of shield method in tunnel construction is limited by the engineering conditions of highwater pressure. This is mainly due to the uncertainty of the pressure-bearing capacity of the sealing chambers of the shield tail under different grades and conditions when subjected to different external water pressures. Therefore, it is crucial to determine the pressure-bearing capacity of the sealing chambers. However, there is a lack of studies on the calculating method of the pressure-bearing capacity, which requires more theoretical investigation. To explore the common patterns of multi-grade sealing-related parameters and quantify the pressure-bearing capacity of the sealing chambers, a breakdown and leakage model of the shield tail is proposed, targeting the basic sealing unit of the system. Based on non-Newtonian fluid dynamics and fractal theory of porous media, the model is used to calculate the breakdown pressure and grease seepage rate corresponding to tunneling and shutdown states. In addition, a hydraulic breakdown device of the sealing unit of the static shield tail is built to investigate the relationship between the shield tail clearance and the shield tail brush porous media area, which helps to verify the theoretical model. Finally, the analysis of sealing chamber geometry parameters, grease rheological parameters, and an environmental parameter using the proposed theoretical model shows that the pressure-bearing capacity of the shield tail can be improved by increasing the shield tail clearance and grease yield stress. It also shows that the length of the sealing chamber and the plastic viscosity of the grease do not have a significant effect on the breakdown pressure of the shield tail. The model proposed in this paper will provide ideas for the calculation of the pressure-bearing capacity of multi-grade sealing chambers in the future.

盾构法在隧道施工中的应用受到高水压工程条件的限制。这主要是由于不同等级和条件下的盾尾密封舱在承受不同外部水压时的承压能力存在不确定性。因此，确定密封腔的承压能力至关重要。然而，有关承压能力计算方法的研究还很缺乏，这需要更多的理论研究。为了探索多级密封相关参数的共同规律，量化密封腔的承压能力，针对系统的基本密封单元，提出了盾尾的击穿和泄漏模型。该模型基于多孔介质的非牛顿流体动力学和分形理论，用于计算隧道状态和停机状态对应的击穿压力和油脂渗漏率。此外，还建立了静态盾尾密封单元的液压击穿装置，研究了盾尾间隙与盾尾刷多孔介质面积之间的关系，有助于验证理论模型。最后，利用所提出的理论模型对密封腔几何参数、润滑脂流变参数和环境参数进行分析，结果表明，通过增加盾尾间隙和润滑脂屈服应力，可以提高盾尾的承压能力。研究还表明，密封腔的长度和润滑脂的塑性粘度对盾尾的击穿压力影响不大。本文提出的模型将为今后计算多级密封腔的承压能力提供思路。

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引用次数: 0

Characteristics of deformation and defect of shield tunnel in coastal structured soil in China 中国沿海结构土盾构隧道变形与缺陷特征

IF 8.2 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2024-10-16 DOI: 10.1016/j.undsp.2024.07.007

Fanyan Meng , Bo Hu , Renpeng Chen , Hongzhan Cheng , Huaina Wu

Shield tunnel is a type of linear underground structure assembled by lining segments, characterized with long joint, weak stiffness, and strict deformation control requirement. The situation of the long-term deformation and defect of the shield tunnel in soft ground in coastal area of China is severe, mainly attributed to the tunneling-induced ground consolidation, frozen cross passage, groundwater pumping, cyclic train load, and nearby construction. Shield tunnel is buried in ground, and the above factors could result in underlying ground settlement, overlying ground loading/unloading, and at-side ground unloading. As a result, the tunnel could suffer from different types of structural deformation and defect. Based upon the aforementioned different reasons, this study investigates the characteristics of the tunnel deformation and defect corresponding to the different types of ground stress change and deformation. It is found that tunneling-induced ground consolidation, frozen cross passage, groundwater pumping, and cyclic train load mainly contribute to the longitudinal differential settlement but negligible transverse convergence, associated with water leakages at circumferential joints. In comparison, surface surcharge and at-side unloading not only cause significant longitudinal differential deformation but also increase transverse lining internal forces, resulting in water leakages at circumferential joints, longitudinal lining concrete cracks and water leakages. Finally, nearby construction could strongly disturb the ground and cause the generation of excess pore-water pressure, making the shield tunnel deformation develops continuously after the nearby construction is completed.

盾构隧道是一种由衬砌分段拼装而成的地下线性结构，具有接头长、刚度弱、变形控制要求严格等特点。我国沿海地区软土地基中盾构隧道的长期变形和缺陷形势严峻，主要原因是掘进引起的地层固结、冻结穿越、地下水抽排、列车循环荷载以及附近施工等。盾构隧道埋于地下，上述因素可能导致地下沉降、上覆地层加载/卸载和边侧地层卸载。因此，隧道可能会出现不同类型的结构变形和缺陷。基于上述不同原因，本研究探讨了不同类型地应力变化和变形所对应的隧道变形和缺陷特征。研究发现，隧道诱发的地层固结、冻结横通道、地下水抽水和列车循环荷载是造成纵向差异沉降的主要原因，而与周向接缝处漏水有关的横向收敛则可以忽略不计。相比之下，地表附加荷载和侧向卸载不仅会造成显著的纵向差异变形，还会增加横向衬砌内力，导致周向接缝处漏水、纵向衬砌混凝土裂缝和漏水。最后，附近施工会强烈扰动地层，导致产生过大的孔隙水压力，使盾构隧道在附近施工结束后变形持续发展。

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引用次数: 0

Experimental study on mechanical behavior and countermeasures of mountain tunnels under strike-slip fault movement 走向滑动断层运动下的山岭隧道力学行为与对策试验研究

IF 8.2 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2024-10-03 DOI: 10.1016/j.undsp.2024.07.006

Zhen Wang , Zilan Zhong , Mi Zhao , Xiuli Du , Jingqi Huang , Hongru Wang

In the seismic mountainous regions such as western China, it is usuallly inevitable to construct tunnels near active fault zones. Those fault-crossing tunnel structures can be extremely vulnerable during earthquakes. Extensive experimental studies have been conducted on the response of continuous mountain tunnels under reverse and normal fault movements, limited experimental investigations are available in the literatures on mountain tunnels with special structural measures crossing strike-slip faults. In this study, a new experimental facility for simulating the movement of strike-slip fault was developed, accounting for the spatial deformation characteristics of large active fault zones. Two groups of sandbox experiment were performed on the scaled tunnel models to investigate the evolution of ground deformation and surface rupture subjected to strike-slip fault motion and its impact on a water conveyance tunnel. The nonlinear response and damage mechanism of continuous tunnels and tunnels incorporated with specially designed articulated system were examined. The test results show that most of slip between stationary block and moving block occurred within the fault core, and significant surface ruptures are observed along the fault strike direction at the fault damage zone. The continuous tunnel undergoes significant shrinkage deformation and diagonal-shear failure near the slip surface and resulted in localized collapse of tunnel lining. The segments of articulated system tunnel suffer a significant horizontal deflection of about 5°, which results in opening and misalignment at the flexible joint. The width of the damaged zone of the articulated system tunnel is about 0.44 to 0.57 times that of the continuous tunnel. Compared to continuous tunnels, the articulated design significantly reduces the axial strain response of the tunnel lining, but increases the circumferential tensile strain at the tunnel crown and invert. It is concluded that articulated design provides an effective measure to reduce the extent of damage in mountain tunnel.

在中国西部等地震多发山区，不可避免地要在活动断层带附近修建隧道。这些穿越断层的隧道结构在地震中非常脆弱。关于连续山岭隧道在逆断层和正断层运动下的响应，已经进行了大量的实验研究，但关于具有特殊结构措施的穿越走向滑动断层的山岭隧道的实验研究还很有限。本研究根据大型活动断层带的空间变形特征，开发了一种新的模拟走向滑动断层运动的实验设施。在按比例制作的隧道模型上进行了两组沙盘实验，研究了走向滑动断层运动时地面变形和地表破裂的演变过程及其对输水隧道的影响。试验研究了连续隧道和采用特殊设计的铰接系统的隧道的非线性响应和破坏机理。试验结果表明，静止块体和移动块体之间的大部分滑移发生在断层核心区，在断层破坏区沿断层走向观察到明显的表面破裂。连续隧道在滑移面附近发生了明显的收缩变形和斜切破坏，导致隧道衬砌局部坍塌。铰接式系统隧道的各段发生了约 5° 的显著水平变形，导致柔性连接处开裂和错位。铰接式隧道受损区的宽度约为连续式隧道的 0.44 至 0.57 倍。与连续隧道相比，铰接式设计大大降低了隧道衬砌的轴向应变响应，但增加了隧道顶部和反向的周向拉伸应变。结论是，铰接式设计是减少山区隧道损坏程度的有效措施。

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引用次数: 0

Detecting soil mixing, grain size distribution, and clogging potential of tunnel excavation face by classification-regression algorithms using EPBM operational data 利用 EPBM 运行数据，通过分类-回归算法检测隧道开挖工作面的土壤混合情况、粒度分布和堵塞潜力

IF 8.2 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2024-10-03 DOI: 10.1016/j.undsp.2024.06.007

Sharmin Sarna, Marte Gutierrez

Earth pressure balance machine (EPBM) operation is sensitive to the properties of the excavated soil due to the requirements of proper soil conditioning and maintenance of necessary chamber pressure. However, soil properties are invariably only available at a limited number of borehole explorations and soil samplings conducted during the subsoil investigation. Thus, it is crucial to identify properties of the tunnel excavation face, such as clay-sand mixed conditions, grain size distributions, and clogging potential along the whole alignment beside the few borehole locations to attain optimally efficient EPBM operation. Therefore, this paper presents the development of machine learning prediction models (i.e., classifiers and regressors) to estimate the properties of the tunnel excavation face using EPBM operational data collected during the tunneling operation as input features. Geotechnical data collected from boreholes and soil samples can be used to validate prediction models and calibrate them. To develop such models, the Northgate Link Extension (N125) tunneling project, constructed in Seattle, Washington, the USA, is used to capture and identify the true ground conditions. The results indicate successful prediction performances by the models, providing indication that EPBM parameters are crucial pointers of the tunnel excavation face properties to help attain optimally efficient EPBM operation.

土压平衡机（EPBM）的运行对挖掘土壤的性质非常敏感，因为需要对土壤进行适当的调节并保持必要的腔室压力。然而，在底土勘察过程中，土壤特性往往只能通过有限的钻孔勘探和土壤取样获得。因此，除了少数几个钻孔位置外，确定隧道开挖面的特性（如粘沙混合状况、粒度分布和整个线路的堵塞潜力）对于实现 EPBM 的最佳高效运行至关重要。因此，本文介绍了机器学习预测模型（即分类器和回归器）的开发情况，利用在隧道开挖过程中收集到的 EPBM 运行数据作为输入特征来估计隧道开挖面的属性。从钻孔和土壤样本中收集的岩土工程数据可用于验证预测模型并对其进行校准。为了开发此类模型，我们使用了在美国华盛顿州西雅图市建造的北门连接线延伸段（N125）隧道项目来捕捉和识别真实的地层条件。结果表明，模型的预测性能非常成功，表明 EPBM 参数是隧道开挖面特性的关键指针，有助于实现 EPBM 的最佳高效运行。

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引用次数: 0

Experimental and numerical investigation of the load-bearing capacity of bolt-fastened wedge active joints for prestressed internal bracing in subway excavations 用于地铁挖掘工程预应力内支撑的螺栓紧固楔形活动接头承载能力的实验和数值研究

IF 8.2 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2024-09-27 DOI: 10.1016/j.undsp.2024.06.006

Chenhe Ge , Pengfei Li , Mingju Zhang , Meng Yang , Weizi Wan

The present study develops a novel type of active joint node-bolt fasten wedge (BFW) active joints, aiming to investigate the load-bearing capacity of a BFW joint in a quantitative way and put forward precise formulas for its yield load and compression rigidity. To achieve this, indoor axial loading tests were conducted on two BFW joints, accompanied by a set of numerical simulations with the finite element approach implemented in ABAQUS. Parametric research was then conducted to assess the impact of various factors on the yield load and initial compression rigidity of BFW joints, leading to the derivation of precise calculation formulas for accurate prediction of these parameters. The key findings indicate that enhancing the bolt strength from 10.9 to 12.9 significantly improves mechanical performance. Under axial compression, the final bearing force, yield load, and initial compression rigidity increase by 0.86, 1.06, and 0.15 times, respectively. Numerical models accurately predict joint behavior under axial force, confirming their reliability. Parameter studies reveal that increasing web and eaves thickness, bolt strength, and diameter improves bearing capacity, while splint thickness has little effect. The fitting formulas introduced can precisely estimate yield load and rigidity, providing practical value for engineering applications.

本研究开发了一种新型节点-螺栓紧固楔（BFW）主动连接，旨在定量研究 BFW 连接的承载能力，并提出其屈服载荷和压缩刚度的精确公式。为此，对两个 BFW 接头进行了室内轴向加载试验，并使用 ABAQUS 中的有限元方法进行了一系列数值模拟。然后进行了参数研究，以评估各种因素对 BFW 接头的屈服载荷和初始压缩刚度的影响，从而推导出精确预测这些参数的精确计算公式。主要研究结果表明，将螺栓强度从 10.9 提高到 12.9 可显著改善机械性能。在轴向压缩条件下，最终承载力、屈服载荷和初始压缩刚度分别增加了 0.86 倍、1.06 倍和 0.15 倍。数值模型准确地预测了轴向力作用下的连接行为，证实了其可靠性。参数研究表明，增加腹板和檐口厚度、螺栓强度和直径可提高承载能力，而夹板厚度影响不大。引入的拟合公式可以精确估算屈服载荷和刚度，为工程应用提供了实用价值。

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引用次数: 0

Numerical studies on the synergistic effects of smoke extraction and control performance by mechanical ventilation shafts during tunnel fires 隧道火灾中机械通风井排烟和控制性能协同效应的数值研究

IF 8.2 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2024-09-27 DOI: 10.1016/j.undsp.2024.07.005

Bin Zhu , Haiyong Cong , Zhuyu Shao , Hairuo Hu , Lili Ye , Yubo Bi , Yiping Zeng

High smoke extraction efficiency and a relatively stable smoke layer stratification are both expected in tunnel ventilation systems. The purpose of this paper is to explore the overall performance of mechanical board-coupled shaft under different ventilation strategies. A total of 57 simulations were conducted, and the effects of the distance between the shaft and board (

h_{D}

) and ventilation velocity on the overall performance were investigated. The results indicate that the performance of smoke extraction and control will be improved by the application of mechanical ventilation and board. Smoke movement patterns under different working conditions were different, for cases of

h_{D} \leq 0.40 m

the smoke could propagate through the whole tunnel without backflow, while for cases of

h_{D} > 0.40 m

, the backflow exists and the smoke movement can be separated into three periods (propagation, stagnation, and retraction). The critical criterion of backflow was investigated and a simple model was deduced to estimate the maximum propagation length. Moreover, the dimensionless time for the smoke flow to reach its maximum propagation length was established. Finally, a comprehensive index

φ

was proposed to evaluate the synergistic effects of smoke extraction and control performance. These studies may provide positive significance for the ventilation design.

隧道通风系统需要较高的排烟效率和相对稳定的烟层分层。本文旨在探讨机械板耦合竖井在不同通风策略下的整体性能。共进行了 57 次模拟，研究了竖井与板之间的距离（hD）和通风速度对整体性能的影响。结果表明，机械通风和板的应用将提高排烟和控烟性能。不同工况下的烟雾运动模式也不同，当 hD≤0.40m 时，烟雾可在整个隧道内传播，不会出现回流现象；而当 hD>0.40m 时，则会出现回流现象，烟雾运动可分为三个时期（传播期、停滞期和回缩期）。研究了回流的临界标准，并推导出一个简单的模型来估算最大传播长度。此外，还确定了烟流达到最大传播长度的无量纲时间。最后，提出了一个综合指标 φ 来评估排烟和控制性能的协同效应。这些研究可为通风设计提供积极意义。

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引用次数: 0

Coal-rock interface real-time recognition based on the improved YOLO detection and bilateral segmentation network 基于改进的 YOLO 检测和双边分割网络的煤岩界面实时识别技术

IF 8.2 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2024-09-26 DOI: 10.1016/j.undsp.2024.07.003

Shuzhan Xu , Wanming Jiang , Quansheng Liu , Hongsheng Wang , Jun Zhang , Jinlong Li , Xing Huang , Yin Bo

To improve the accuracy and efficiency of coal-rock interface recognition, this study proposes a model built on the real-time detection algorithm, you only look once (YOLO), and the lightweight bilateral segmentation network. Simultaneously, the regional similarity transformation function and dragonfly algorithm are introduced to enhance the quality of coal-rock images. The comparison with three other models demonstrates the superior edge inference performance of the proposed model, achieving a mean Average Precision (mAP) of 90.2 at the Intersection over Union (IoU) threshold of 0.50 (mAP₅₀) and 81.4 across a range of IoU thresholds from 0.50 to 0.95 (mAP_[50,95]). Furthermore, to maintain high accuracy and real-time recognition capabilities, the proposed model is optimized using the open visual inference and neural network optimization toolkit, resulting in a 144.97% increase in the mean frames per second. Experimental results on four actual coal faces confirm the efficacy of the proposed model, showing a better balance between accuracy and efficiency in coal-rock image recognition, which supports further advancements in coal mining intelligence.

为了提高煤岩界面识别的准确性和效率，本研究提出了一种基于实时检测算法 "只看一次（YOLO）"和轻量级双边分割网络的模型。同时，还引入了区域相似性变换函数和蜻蜓算法，以提高煤岩图像的质量。与其他三种模型的比较结果表明，所提出的模型具有卓越的边缘推断性能，在交集大于联合（IoU）阈值为 0.50 时，平均精度（mAP）为 90.2（mAP50），在 IoU 阈值为 0.50 到 0.95 的范围内，平均精度（mAP[50,95]）为 81.4。此外，为了保持高精确度和实时识别能力，还使用开放式视觉推理和神经网络优化工具包对所提出的模型进行了优化，使平均每秒帧数提高了 144.97%。在四个实际煤炭工作面的实验结果证实了所提模型的有效性，表明在煤岩图像识别的准确性和效率之间取得了更好的平衡，从而为煤矿智能化的进一步发展提供了支持。

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引用次数: 0

Experimental investigation on damage development and failure mechanism of shield tunnel lining under internal blast considering stratum-structure interaction 考虑地层-结构相互作用的盾构隧道衬砌在内部爆破下的损伤发展和破坏机理的实验研究

IF 8.2 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2024-09-26 DOI: 10.1016/j.undsp.2024.07.004

Chao Liu , Guanhua Zhao , Yijie Liu , Jie Cui , Hai Liu , Shunhang Zhu

With the expansion of international terrorism and the potential threat of attacks against civil infrastructure, the dynamic response and failure modes of underground tunnels under explosive loads have become a prominent research topic. The high cost and inherent danger associated with explosion experiments have limited current research on tunnel internal explosions, particularly in the context of scaled model tests of shield tunnels. This study presents a series of scaled model tests under 1g-condition simulating internal blast events within a shield tunnel based on the prototype of the Shantou Bay Tunnel, considering the influences of surrounding stratum and equivalent explosive yield. Three different TNT explosive yields are considered in the model tests, namely 0.2, 0.4, and 1.0 kg. The model tests focus on the damage behavior and collapse modes of the shield tunnel lining under internal explosive loads. The model tests reveal that the shield tunnel is prone to damage at the joints of the tunnel crown and shoulder when subjected to internal explosive loads, with the upper half of the tunnel lining experiencing segment collapse, while the lower half remains largely undamaged. As the TNT equivalent increases, the damage area at the tunnel joints expands, and the number of segment failures in the upper half of the tunnel rises, transitioning from a damaged state to a collapsed state. The influence of “stratum-structure” interaction is investigated by comparing two models, one with overburden soil and the other positioned at the ground surface. The model tests reveal that the presence of soil pressure and confinement can significantly enhance the tunnel resistance to internal blast loads. Based on the observation of the model tests, five different damage modes of segment joints under internal explosion are proposed in this study.

随着国际恐怖主义的扩大和民用基础设施受到攻击的潜在威胁，地下隧道在爆炸载荷作用下的动态响应和失效模式已成为一个突出的研究课题。爆炸实验的高成本和固有危险性限制了目前对隧道内部爆炸的研究，特别是在盾构隧道的比例模型试验中。本研究以汕头海湾隧道原型为基础，考虑了周围地层和当量爆炸当量的影响，在 1g 条件下进行了一系列模拟盾构隧道内部爆炸事件的比例模型试验。模型试验考虑了三种不同的 TNT 爆炸当量，即 0.2、0.4 和 1.0 千克。模型试验的重点是盾构隧道衬砌在内部爆炸荷载作用下的破坏行为和坍塌模式。模型试验结果表明，盾构隧道在承受内部爆炸荷载时，隧道顶部和肩部的接缝处容易发生损坏，隧道衬砌的上半部分会发生分段坍塌，而下半部分则基本没有损坏。随着 TNT 当量的增加，隧道接缝处的损坏面积扩大，隧道上半部分的分段坍塌数量增加，从损坏状态过渡到坍塌状态。通过比较两个模型，一个是覆土模型，另一个是位于地表的模型，研究了 "地层-结构 "相互作用的影响。模型试验显示，土壤压力和封闭的存在可显著增强隧道对内部爆炸荷载的抵抗力。根据模型试验的观察结果，本研究提出了五种不同的内爆条件下节段连接的破坏模式。

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引用次数: 0

RM2D: An automated and robust laser-based framework for mobile tunnel deformation detection RM2D：基于激光的移动隧道变形自动稳健检测框架

IF 8.2 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2024-09-16 DOI: 10.1016/j.undsp.2024.07.002

Boxun Chen , Ziyu Zhao , Lin Bi , Zhuo Wang

As mining operations extend to greater depths, the risk of deformation in high-stress tunnels increases significantly, posing a substantial threat. This study introduces a novel framework known as “robust mobility deformation detection” (RM2D), designed for real-time tunnel deformation detection. RM2D employs mobile LiDAR scanner to capture real-time point cloud data within the tunnel. This data is then voxelized and analyzed using covariance matrices to create a voxel-based multi-distribution representation of the rugged tunnel surface. Leveraging this representation, we assess deformations and scrutinize results through machine learning models to swiftly pinpoint tunnel deformation locations. Extensive experimental validation confirms the framework’s capacity to successfully detect deformations, including floor heave, side rib spalling, and roof fall, with remarkable accuracy. For deformation levels at 0.15 m, RM2D was able to successfully detect deformations with an area greater than 2 m². For deformation areas of (3 ± 0.5) m², RM2D successfully detected deformations of levels at (0.05 ± 0.01) m, and its detection capability meets the standard criteria for mining tunnel deformation detection. When compared to two conventional methods, RM2D demonstrates its real-time deformation detection capability in complex environments and on rough surfaces with precision, all at speeds below 10 km/h. Furthermore, we evaluated the predictive performance using multiple evaluation metrics and provided insights into the decision mechanism of the machine learning employed in our research, thereby offering valuable information for practical engineering applications in tunnel deformation detection.

随着采矿作业向更深的深度延伸，高应力隧道的变形风险显著增加，构成了巨大的威胁。本研究介绍了一种被称为 "鲁棒移动变形检测"（RM2D）的新型框架，专为实时检测隧道变形而设计。RM2D 利用移动式激光雷达扫描仪捕捉隧道内的实时点云数据。然后，使用协方差矩阵对这些数据进行体素化和分析，以创建基于体素的崎岖隧道表面多分布表示法。利用这种表示方法，我们通过机器学习模型评估变形并仔细检查结果，从而迅速确定隧道变形位置。广泛的实验验证证实了该框架能够成功检测变形，包括底板隆起、侧肋剥落和顶板塌陷，而且精确度极高。对于 0.15 米的变形水平，RM2D 能够成功检测到面积大于 2 平方米的变形。在变形面积为（3 ± 0.5）平方米时，RM2D 能成功检测出（0.05 ± 0.01）米的变形水平，其检测能力达到了矿山隧道变形检测的标准。与两种传统方法相比，RM2D 展示了其在复杂环境和粗糙表面上精确的实时变形检测能力，所有检测速度均低于 10 km/h。此外，我们还使用多个评估指标对预测性能进行了评估，并深入分析了研究中采用的机器学习的决策机制，从而为隧道变形检测的实际工程应用提供了有价值的信息。

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引用次数: 0

Lightweight defocus deblurring network for curved-tunnel line scanning using wide-angle lenses 使用广角镜头进行曲线隧道线扫描的轻量级去焦模糊网络

IF 8.2 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2024-09-13 DOI: 10.1016/j.undsp.2024.06.005

Shaojie Qin , Taiyue Qi , Xiaodong Huang , Xiao Liang

High-resolution line scan cameras with wide-angle lenses are highly accurate and efficient for tunnel detection. However, due to the curvature of the tunnel, there are variations in object distance that exceed the depth of field of the lens, resulting in uneven defocus blur in the captured images. This can significantly affect the accuracy of defect recognition. While existing deblurring algorithms can improve image quality, they often prioritize results over inference time, which is not ideal for high-speed tunnel image acquisition. To address this issue, we developed a lightweight tunnel structure defect deblurring network (TSDDNet) for curved-tunnel line scanning with wide-angle lenses. Our method employs an innovative progressive structure that balances network depth and feature breadth to simultaneously achieve good performance and short inference time. The proposed depthwise ResBlocks significantly improves the parameter efficiency of the network. Additionally, the proposed feature refinement block captures the structurally similar features to enhance the image details, increasing the peak signal-to-noise ratio (PSNR). A raw dataset containing tunnel blur images was created using a high-resolution line scan camera and used to train and test our model. TSDDNet achieved a PSNR of 26.82 dB and a structural similarity index measure of 0.888, while using one-third of the parameters of comparable alternatives. Moreover, our method exhibited a higher computational speed than that of conventional methods, with inference times of 8.82 ms for a single 512 × 512 pixels image patch and 227.22 ms for completely processing a 2048 × 2560 pixels image. The test results indicated that the structural scalability of the network allows it to accommodate large inputs, making it effective for high-resolution images.

配备广角镜头的高分辨率线扫描相机在隧道探测方面具有高精确度和高效率。然而，由于隧道的弧度，物体距离的变化会超过镜头的景深，从而导致捕捉到的图像出现不均匀的虚焦模糊。这会严重影响缺陷识别的准确性。虽然现有的去模糊算法可以提高图像质量，但它们通常会优先考虑结果而不是推理时间，这对于高速隧道图像采集来说并不理想。为了解决这个问题，我们开发了一种轻型隧道结构缺陷去毛刺网络（TSDDNet），用于使用广角镜头进行曲线隧道线扫描。我们的方法采用了创新的渐进式结构，在网络深度和特征广度之间取得了平衡，从而同时实现了良好的性能和较短的推理时间。所提出的深度ResBlocks大大提高了网络的参数效率。此外，提出的特征细化块能捕捉结构相似的特征，从而增强图像细节，提高峰值信噪比（PSNR）。我们使用高分辨率线扫描相机创建了一个包含隧道模糊图像的原始数据集，用于训练和测试我们的模型。TSDDNet 的 PSNR 为 26.82 dB，结构相似度指数为 0.888，而使用的参数仅为同类替代方法的三分之一。此外，与传统方法相比，我们的方法具有更高的计算速度，单个 512 × 512 像素图像片段的推理时间为 8.82 毫秒，完全处理一幅 2048 × 2560 像素图像的推理时间为 227.22 毫秒。测试结果表明，该网络的结构可扩展性使其能够适应大型输入，从而有效地处理高分辨率图像。

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