Tunnelling and Underground Space Technology最新文献_第10页

Influence of inclined groove on rock-crushing behavior of TBM cutter 斜槽对TBM刀具破岩性能的影响

IF 7.4 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2026-01-06 DOI: 10.1016/j.tust.2025.107404

Xuhui Zhang , Zeren Peng , Hanwen Lai , Shenghui Kang , Yashi Liao , Yimin Xia

To investigate the impact of groove angle on rock-crushing behavior of a TBM cutter, the finite element method was employed to simulate both rock cutting and rock-crushing processes. Then, the average vertical load, average rolling load, and specific energy required for rock-crushing by TBM cutter were calculated and analyzed under varying groove angles and groove spacings. Furthermore, some rock-crushing tests were performed to show the cutter’s crushing behavior regarding the groove angle and groove spacing. The study’s results indicate that the effectiveness of crack propagation to the groove is influenced by the groove angle and groove spacing. Specifically, for the given groove angle, when the groove spacing remains at a low value, the cracks produced can effectively extend to grooves. However, when the groove spacing surpasses a certain threshold, the cracks fail to sufficiently reach the grooves. This threshold is referred to as the critical groove spacing, which varies with different groove angles. Notably, as the groove angle increases, the critical groove spacing also tends to increase. Furthermore, when the two cutting grooves can facilitate rock crushing, a rise from 0° to 60° in the groove angle results in a decrease in both the cutter’s vertical load and rolling load. Additionally, the specific energy initially falls and then rises with the growth of the groove angle. An optimal groove spacing that minimizes the specific energy exists for a certain groove angle. In particular, the optimal groove spacings at groove angles of 0°, 15°, 30°, 45°, and 60° are 70 mm, 70 mm, 80 mm, 80 mm, and 90 mm, respectively. Notably, when the grooves with different groove angles and groove spacings can provide an auxiliary crushing effect, the crushing load of the cutter is minimized at a groove angle of 60°, while the specific energy of the cutter reaches its lowest point at a groove angle of 30°.

为了研究槽角对TBM刀具破岩性能的影响，采用有限元方法模拟了切削和破岩过程。然后，计算分析了不同槽角和槽距条件下TBM刀破碎岩石所需的平均垂直载荷、平均滚动载荷和比能。此外，还进行了一些岩石破碎试验，以显示切割器在槽角和槽距方面的破碎行为。研究结果表明，裂纹扩展到沟槽的有效性受沟槽角度和沟槽间距的影响。在沟槽角度一定的情况下，当沟槽间距保持在一定值时，裂纹能够有效地扩展到沟槽中。然而，当沟槽间距超过一定阈值时，裂纹不能充分到达沟槽。这个阈值称为临界槽距，它随槽角的不同而变化。值得注意的是，随着槽角的增大，临界槽距也有增大的趋势。当两个切槽有利于破碎岩石时，当切槽角度从0°增大到60°时，切刀的垂直载荷和滚动载荷均减小。随着槽角的增大，比能呈先下降后上升的趋势。在一定的槽角下，存在比能量最小的最佳槽距。其中，槽角为0°、15°、30°、45°和60°时的最佳槽间距分别为70 mm、70 mm、80 mm、80 mm和90 mm。值得注意的是，当不同凹槽角度和凹槽间距的凹槽能够提供辅助破碎作用时，刀具的破碎载荷在凹槽角度为60°时最小，而刀具的比能在凹槽角度为30°时达到最低点。

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引用次数: 0

Groundwater inflow into tunnels: semi-empirical methods for estimating steady state inflow associated with excavation induced drawdown 隧道的地下水流入：估计开挖诱导下降的稳态流入的半经验方法

IF 7.4 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2026-01-06 DOI: 10.1016/j.tust.2025.107430

Simone L. Markus, Mark S. Diederichs

Estimation of groundwater inflow is essential for tunnel design and construction; however, analytical solutions used in current engineering practice have limited applicability, especially in cases where drawdown of the water table occurs due to excavation associated drainage. Existing methods for estimating steady state groundwater inflow under a drawn-down water table require improvement, as they typically assume fixed water table boundaries. This article unites and compares classical inflow formulations and reviews their applicability and limitations. Based on numerical modelling, the study proposes two novel methods for estimating inflow into tunnels based on drawdown: one for inflow into shallow tunnels where full drawdown of the water table occurs (trench-like inflow), and one for inflow into moderately deep tunnels, where partial drawdown of the water table occurs. The inflow-drawdown relationship devised accounts for the influence of tunnel size and depth on drawdown shape, and is independent of assumptions of boundary conditions, which limit applicability of other equations. Additionally, practical guidance for numerical modelling of tunnels below the water table is provided, including sensitivity analysis of boundary conditions.

地下水位估算是隧道设计和施工的重要内容。然而，目前工程实践中使用的解析解的适用性有限，特别是在由于开挖相关排水而导致地下水位下降的情况下。现有的在下降的地下水位下估计稳态地下水流入的方法需要改进，因为它们通常假设固定的地下水位边界。本文对经典的流入公式进行了统一和比较，并对其适用性和局限性进行了评述。在数值模拟的基础上，本研究提出了两种基于水位下降估算隧道入流的新方法：一种用于水位完全下降的浅埋隧道入流（沟槽式入流），另一种用于水位部分下降的中深埋隧道入流。所设计的流降关系考虑了隧道尺寸和深度对流降形状的影响，并且不依赖于限制其他方程适用性的边界条件假设。此外，本文还为地下隧道的数值模拟提供了实用的指导，包括边界条件的敏感性分析。

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引用次数: 0

A “Proactive-Prevention and Post-Resistant” support method for alleviating rockburst in deep-buried large-section tunnels 缓解深埋大断面隧道岩爆的“先防后抗”支护方法

IF 7.4 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2026-01-06 DOI: 10.1016/j.tust.2025.107402

Fengqiang Gong , Zhixuan Zhang , Bo Wang , Jinhao Dai , Pengyu Ma

Rockburst persistently challenge the safe construction of large-section hard rock tunnels under high geostress environments. At present, the insufficient adaptability of conventional active support strategy which is “Excavate First and Then Support” (EFTS) has limitations in the prevention of the dynamic damage of rockburst. To address the limitations of rockburst prevention, this study proposes a “Proactive-Prevention and Post-Resistant” support (PPS) method for dynamic stability control, which consists of two consecutive steps. First, an initial tunnel with reduced diameter is excavated, followed by installation of pre-stressed rockbolt beyond the designed profile to establish an advanced pressure arch. Subsequently, the tunnel is expanded to the designed cross-section with supplementary reinforcement measures. This new strategy collaboratively combines the stress redistribution effect caused by the initial tunnel geometry, thereby alleviating the degradation of surrounding rock strength caused by excavation and improving the stability of the rock mass. In addition, this strategy takes advantage of the energy absorption capacity of pre-stressed anchor rods, effectively suppressing the risks associated with instantaneous energy release. A case study was conducted on the diversion tunnel No.3 of the Jinping II hydropower station. The evolution of advanced pressure arch boundaries under varying initial tunnel diameters was systematically investigated, as well as the effectiveness of the PPS method. Validation results demonstrate that compared to EFTS support strategy, the PPS method significantly reduces rockburst intensity from widespread moderate to severe rockburst to none or minor rockburst. Mechanistic analysis confirms that this strategy effectively minimizes tangential stress concentration by optimizing pressure arch geometry while enhancing energy dissipation efficiency. The PPSmethod provides a new perspective and methodology for rockburst mitigation in deep large-section hard rock tunnels.

在高地应力环境下，冲击地压对大断面硬岩隧道的安全施工提出了严峻的挑战。目前，传统的主动支护策略“先挖后支护”（EFTS）适应性不足，在防治岩爆动力损伤方面存在一定的局限性。针对岩爆防治的局限性，提出了一种由两个连续步骤组成的“前防后抗”支护（PPS）动态稳定控制方法。首先，挖掘直径减小的初始隧道，然后在设计剖面之外安装预应力锚杆以建立先进的压力拱。随后，通过补充加固措施将隧道扩展至设计截面。这种新策略协同结合了隧道初始几何形状引起的应力重分布效应，从而缓解了开挖引起的围岩强度退化，提高了岩体稳定性。此外，该策略利用了预应力锚杆的吸能能力，有效地抑制了瞬时能量释放带来的风险。系统研究了不同初始隧洞直径条件下超前压力拱边界的演化规律，并验证了PPS方法的有效性。验证结果表明，与EFTS支护策略相比，PPS方法显著降低了岩爆强度，从普遍的中度至重度岩爆到无岩爆或轻度岩爆。力学分析证实，该策略通过优化压拱几何形状，有效降低切向应力集中，同时提高能量耗散效率。该方法为深埋大断面硬岩巷道岩爆防治提供了新的视角和方法。

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引用次数: 0

Dynamic prediction of surrounding rock grades in TBM tunnels based on physics–data dual-driven model 基于物理-数据双驱动模型的TBM隧道围岩等级动态预测

IF 7.4 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2026-01-05 DOI: 10.1016/j.tust.2025.107311

Kang Fu , Yiguo Xue , Daohong Qiu , Fanmeng Kong , Jianning Wang

Accurate and dynamic identification of surrounding rock grades in TBM tunnels is crucial for ensuring excavation safety and improving construction efficiency. This study proposes a hybrid modeling method based on a physics-data dual-driven approach to achieve high-precision dynamic identification of surrounding rock grades. First, the Isolation Forest model is employed to eliminate outliers from the raw tunneling data, and the key tunneling parameters influencing rock grades are identified using mutual information. Then, the Seasonal and Trend decomposition using LOESS (STL) model is used to perform multimodal decomposition on the dominant tunneling parameters, obtaining the corresponding trend, periodic, and residual components. Subsequently, an Improved Refined Composite Multiscale Sample Entropy (IRCMSE) model is adopted to calculate the feature entropy of each component, forming a dynamic sample database for the data-driven model. Based on this, an improved Convolutional Neural Network – Long Short-Term Memory (CNN-LSTM) model is developed to realize data-driven dynamic identification of TBM tunnel strata. Furthermore, a variation identification formula for surrounding rock grades was proposed based on the principle of geological continuity, enabling physics-driven dynamic identification of surrounding rock grades in TBM tunnels. On this basis, a fusion method combining the physical-driven model and the data-driven model is proposed. The constructed physics-data dual-driven model achieves average precision, recall, F1-score, and accuracy of 98.29 %, 97.98 %, 98.13 %, and 98.30 %, respectively, representing an average improvement of 2.17 % over the data-driven model and 15.07 % over the physical-driven model. Engineering validation results indicate that the overall performance of the model decreases by only 1.74 % and 5.29 % under similar and different geological conditions, respectively, demonstrating strong generalization and robustness, and meeting the requirements of intelligent TBM tunneling under complex geological conditions.

隧道掘进机隧道围岩等级的准确动态识别对于保证开挖安全、提高施工效率至关重要。提出了一种基于物理数据双驱动的混合建模方法，实现了围岩等级的高精度动态识别。首先，采用隔离森林模型剔除原始掘进数据中的异常值，利用互信息识别影响岩石品位的关键掘进参数；然后，利用黄土（STL）模型进行季节和趋势分解，对优势参数进行多模态分解，得到相应的趋势分量、周期分量和残差分量。随后，采用改进的精细复合多尺度样本熵（IRCMSE）模型计算各分量的特征熵，形成数据驱动模型的动态样本库。在此基础上，提出了一种改进的卷积神经网络-长短期记忆（CNN-LSTM）模型，实现了数据驱动的TBM隧道地层动态识别。在此基础上，提出了基于地质连续性原理的围岩等级变异识别公式，实现了TBM隧道围岩等级的物理驱动动态识别。在此基础上，提出了一种物理驱动模型与数据驱动模型相结合的融合方法。所构建的物理-数据双驱动模型的平均精密度、查全率、f1得分和准确率分别达到98.29%、97.98%、98.13%和98.30%，比数据驱动模型平均提高2.17%，比物理驱动模型平均提高15.07%。工程验证结果表明，该模型在相似地质条件和不同地质条件下的综合性能仅下降1.74%和5.29%，具有较强的通用性和鲁棒性，满足复杂地质条件下智能隧道掘进机掘进的要求。

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引用次数: 0

A numerical study of damage evolution and crack propagation in backfill bodies of high-temperature thermal energy storage cavities in mines 矿山高温储热腔充填体损伤演化与裂纹扩展数值研究

IF 7.4 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2026-01-04 DOI: 10.1016/j.tust.2025.107362

Rui Zhan, Bo Zhang, Lang Liu, Chao Huan, Huisheng Qu, Huicong Xu, Jin Zhang, Hongjun Xi

The utilization of goafs for building high-temperature thermal energy storage cavities is an effective approach to large-scale solar thermal energy storage. However, its long-term stability is constrained by the damage evolution and crack propagation of the backfill body under thermo-mechanical coupling effects. To address this, this study establishes a thermo-mechanical-damage coupled model based on elastic damage theory to describe the damage behavior of the backfill body under thermal expansion effects. Damage evolution is jointly governed by the maximum tensile stress criterion and the Drucker-Prager criterion. The model’s accuracy is validated through numerical simulations, high-temperature uniaxial compression tests on backfill bodies, and comparisons with analytical solutions. Based on this model, the crack propagation and damage evolution patterns during long-term operation of the thermal energy storage cavity are investigated. Results indicate that the circular thermal energy storage cavity, due to its axisymmetric structure, facilitates a uniform distribution of thermal stresses. Radial thermal expansion is converted into uniform circumferential stresses, thereby reducing local stress concentrations. Storage temperature is a key factor controlling backfill body damage. The damage growth rate reaches as much as 56.8 % in the high-temperature range of 400 °C to 450 °C, significantly higher than the 16.8 % growth rate observed between 300 °C and 350 °C. Under low vertical stress conditions, damage zones in the backfill body remain controllable without crack propagation. Conversely, high vertical stress induces coupling between stress concentration and the thermal softening effect, leading to tensile damage at the top and bottom of the thermal energy storage cavity and ultimately resulting in crack formation. Furthermore, maintaining a spacing between adjacent thermal energy storage cavities on the same level that exceeds 1.5 times the cavity diameter effectively mitigates the risk of overall instability caused by the interconnection of damage zones. This study provides theoretical foundations and technical references for the safe design of high-temperature thermal energy storage cavities in mine goaf areas.

利用采空区建造高温储热腔是实现大规模太阳能蓄热的有效途径。但其长期稳定性受到充填体在热-力耦合作用下的损伤演化和裂纹扩展的制约。为此，本研究基于弹性损伤理论建立了热膨胀作用下充填体的热-机-损伤耦合模型来描述充填体的损伤行为。损伤演化受最大拉应力准则和Drucker-Prager准则共同支配。通过数值模拟、回填体高温单轴压缩试验以及与解析解的比较，验证了模型的准确性。基于该模型，研究了蓄热腔在长期运行过程中的裂纹扩展和损伤演化模式。结果表明，圆形储热腔由于其轴对称结构，有利于热应力的均匀分布。径向热膨胀转化为均匀的周向应力，从而减少了局部应力集中。贮存温度是控制充填体损伤的关键因素。在400 ~ 450℃的高温范围内，损伤增长率高达56.8%，显著高于300 ~ 350℃的16.8%。在低竖向应力条件下，充填体内部损伤区域保持可控，不发生裂纹扩展。反之，高垂直应力会引起应力集中与热软化效应耦合，导致储热腔顶部和底部出现拉伸损伤，最终形成裂纹。此外，保持相邻储热腔之间在同一水平上的间距超过1.5倍的腔径，有效地减轻了由于损伤区互连而导致的整体不稳定的风险。本研究为矿山采空区高温储热空腔的安全设计提供了理论依据和技术参考。

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引用次数: 0

TTM: A concise yet effective surface reconstruction approach for tunnel point cloud from mobile mapping system TTM：一种基于移动测绘系统的隧道点云地表重建方法

IF 7.4 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2026-01-03 DOI: 10.1016/j.tust.2025.107411

Hao Cui , Jian Li , Qingwu Hu , Long He , Yiwen Tao , Lei Xu , Qingzhou Mao

Tunnels are critical infrastructure, the surface reconstruction of their point cloud is essential for applications such as reality capture BIM and digital twin systems. While mobile mapping systems (MMS) represent an efficient approach for acquiring tunnel point clouds, existing surface reconstruction methods suffer from low efficiency and poor geometric fidelity in tunnel environments. This paper proposes TTM (topology transfer meshing), a concise yet efficient surface reconstruction method for MMS-acquired tunnel point clouds. The approach employs an occlusion-free projection to map 3D point clouds onto a 2D plane, constructs a 2D Delaunay triangulation, and subsequently transfers the mesh topology back to 3D space through a topology transfer mechanism. Qualitative and quantitative experiments conducted on point cloud datasets totaling over 6 km of subway, high-speed rail, and highway tunnels, comprising more than 1 billion points, demonstrate that our method outperforms both conventional and deep learning-based surface reconstruction approaches in both computational efficiency and geometric fidelity. Additional experiments confirm the method’s robust meshing capability with decimated point clouds while revealing heightened sensitivity to point clouds containing substantial measurement errors. Beyond tunnel engineering, this technique extends to digital modeling of linear infrastructure, including pipelines and utility tunnels, providing efficient technical support for intelligent operation and maintenance.

隧道是关键的基础设施，其点云的表面重建对于现实捕获BIM和数字孪生系统等应用至关重要。虽然移动测绘系统（MMS）是一种获取隧道点云的有效方法，但现有的表面重建方法在隧道环境中存在效率低和几何保真度差的问题。本文提出了一种简洁而高效的mms获取隧道点云表面重建方法TTM（拓扑转移网格）。该方法采用无遮挡投影将三维点云映射到二维平面上，构建二维Delaunay三角剖分，随后通过拓扑转移机制将网格拓扑转移回三维空间。在总计超过6公里的地铁、高速铁路和公路隧道的点云数据集上进行的定性和定量实验表明，我们的方法在计算效率和几何保真度方面优于传统和基于深度学习的表面重建方法。额外的实验证实了该方法对大量点云的鲁棒网格划分能力，同时揭示了对包含大量测量误差的点云的更高灵敏度。除了隧道工程，该技术还扩展到线性基础设施的数字建模，包括管道和公用隧道，为智能运维提供有效的技术支持。

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引用次数: 0

Dynamic response of an underwater single-tube double-track tunnel under high-speed train loads: experimental and numerical investigation 高速列车荷载作用下水下单管双线隧道动力响应：试验与数值研究

IF 7.4 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2026-01-03 DOI: 10.1016/j.tust.2025.107425

Zhi Ding , Chaofeng Chen , Yang Chen , Honglei Sun , Hai Xia , Zhenhua Chen , Xiao Zhang

The single-tube double-track underwater tunnel has gained prominence in recent years due to its practicality. Given the unique structural configuration, systematic investigation into the dynamic responses of this type of tunnels under train loads holds substantial practical value. This study adopts a technical route combining physical model testing and numerical simulation, conducting systematic research on the coupled scenario of “high water pressure–high-speed train load–large-diameter tunnel–single-tube double-track”. Peak particle acceleration (PPA) and frequency response function (FRF) were employed as key indicators to evaluate dynamic behavior. The results indicated that higher train speeds elevated the intensity of dynamic response magnitude along the segments, while the overall shape of the envelope remained consistent. Additionally, key response quantities (e.g., PPA and excess PWP) in the surrounding soil increased with train speed, showing nonlinear variation characteristics, with higher values observed in the upper and lower zones. While initial saturation amplified the dynamic response compared to dry conditions, both the peak acceleration and displacement were suppressed as hydrostatic water pressure increased. The similar suppressive effect was observed in the excess PWP response (whether overall magnitude or oscillations induced by train loads) of soil, possibly due to the additional lateral constraint effects. Compared to unidirectional loading, bidirectional loading notably increased the peak acceleration response and fluctuation amplitude of internal forces in the tunnel structure as well as the excess PWP response in the surrounding soil, while the magnitudes of these increases varied across different locations. Meanwhile, stress and strain responses in the surrounding soil concentrated primarily above and below the tunnel during the meeting of train crossings. The findings of this study provide insights for the construction and design of single-tube double-track underwater tunnel.

近年来，单管双轨水下隧道因其实用性而备受关注。由于其独特的结构形式，系统研究列车荷载作用下该类隧道的动力响应具有重要的实用价值。本研究采用物理模型试验与数值模拟相结合的技术路线，对“高水压-高铁-大直径隧道-单管双轨”耦合场景进行了系统研究。采用峰值粒子加速度（PPA）和频率响应函数（FRF）作为评价动态行为的关键指标。结果表明，列车运行速度越快，动力响应强度越高，而包络线的整体形状保持不变。此外，周边土壤关键响应量（如PPA和过剩PWP）随列车速度的增加而增加，呈现非线性变化特征，上下区域均较高。与干燥条件相比，初始饱和放大了动态响应，但随着静水压力的增加，峰值加速度和位移均受到抑制。类似的抑制效应在土壤的过量PWP响应（无论是总体幅度还是由火车负载引起的振荡）中被观察到，可能是由于额外的横向约束效应。与单向加载相比，双向加载显著增加了隧道结构的峰值加速度响应、内力波动幅值以及周围土体的超PWP响应，但不同位置的增加幅度有所不同。同时，列车道口交汇时，隧道周围土体的应力应变响应主要集中在隧道上方和下方。研究结果为单管双轨水下隧道的施工设计提供了参考。

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引用次数: 0

Mechanical performance and damage characteristics of segmental joints in semi-rigid element immersed tunnel under bending deformation: A combined experimental and numerical study 弯曲变形下半刚性单元沉管隧道分段节理力学性能及损伤特征：试验与数值结合研究

IF 7.4 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2026-01-03 DOI: 10.1016/j.tust.2025.107427

Zhinan Hu , Yuejian Wang , Shaobo Qin , Shunde Yin , Haiyang Pan , Kaimeng Ma

The mechanical performance of segmental joints in semi-rigid element immersed tunnels is influenced significantly by differential settlement. The mechanical behaviors and failure mechanisms of segmental joints under longitudinal differential settlement were investigated in this study. The validity of the numerical simulation methods was verified through 1:10 scale physical model tests. Subsequently, a full-scale segmental joint model of the Hong Kong-Zhuhai-Macao Bridge (HZMB) immersed tunnel was established. Systematic analyses of the mechanical responses, damage evolution, and sensitive damage zones were conducted. Based on the observations, an optimized design scheme was proposed. It provides theoretical and technical support for structural health monitoring and optimization. The results indicate that the bending resistance of semi-rigid element segment joints is provided primarily by the prestressed cables on the open side. As the rotation angle increases, the rotation center moves upward, and the contact stress concentrates on the top plate. The shear force of the shear keys first decreases and then increases. This is related to their mechanical performance. Shear keys function mainly in shear rather than bending. Tensile and compressive damage concentration zones oriented at 45° form near the shear keys in both middle-wall and side-walls of the segments. The tensile damage at the side-wall shear keys occurs earlier. At 0.004 rad, tensile damage is observed at the middle-wall shear keys (also oriented at 45°). Based on the damage characteristics of the segmental joint, an optimized design scheme using high ductility concrete (HDC) for vertical shear keys was proposed. After optimization, the toughness of the shear keys was enhanced significantly, and the plastic damage was delayed effectively.

半刚性单元沉管隧道分段节理的力学性能受不均匀沉降的显著影响。研究了纵向差异沉降作用下节理的力学行为和破坏机制。通过1:10比例物理模型试验验证了数值模拟方法的有效性。随后，建立了港珠澳大桥沉管隧道全尺寸节理模型。对结构的力学响应、损伤演化和损伤敏感区进行了系统分析。在此基础上，提出了优化设计方案。为结构健康监测和优化提供理论和技术支持。结果表明：半刚性单元节段节点的抗弯能力主要由开口侧预应力索提供；随着旋转角度的增大，旋转中心向上移动，接触应力集中在顶板上。剪切键的剪切力先减小后增大。这与它们的机械性能有关。剪切键的作用主要是剪切而不是弯曲。在中、侧壁剪切键附近均形成45°方向的拉压损伤集中区。侧壁剪力键处的拉伸损伤发生较早。在0.004 rad时，在中壁剪切键处观察到拉伸损伤（同样方向为45°）。根据节理节点的损伤特点，提出了采用高延性混凝土（HDC）进行竖向剪力键优化设计的方案。优化后，剪切键的韧性得到显著提高，塑性损伤得到有效延缓。

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引用次数: 0

Full-scale experimental study of flame behavior and thermal distribution in utility tunnel fires 公用事业隧道火灾火焰特性及热分布的全尺寸实验研究

IF 7.4 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2026-01-02 DOI: 10.1016/j.tust.2025.107439

Xiaojiang Liu , Zhao-Dong Xu , Jun Dai , Jiayu Che , Zhong-Wei Hu , Defu Che

A series of full-scale fire experiments were conducted in the largest utility tunnel platform in China (100 m × 3 m × 3 m), aiming to investigate the flame behavior and thermal flow evolution of utility tunnel fires. Both oil pool fires and cable fires were employed to realistically replicate fire scenes while maintaining reasonable costs. The heat release rates, ventilation conditions, multiple fire sources, and cable arrangements were analyzed comprehensively. Oil pool fires were conducted to simulate the thermal output of early-stage cable fires, results under ventilated conditions demonstrated downstream shifts in peak temperatures and asymmetric longitudinal temperature distributions due to interactions between hot smoke and opposing airflow. In cable fires, heat release accumulates through layer-by-layer ignition pattern. The flame initially propagates vertically, then transitions to longitudinal spread after sufficient thermal accumulation. Based on these findings, shutting down ventilation and sealing openings during early fire stages is recommended to limit oxygen supply, as analyzed from ventilation tests under both oil pool and cable fire cases. Optimizing cable layout can further mitigate vertical flame spread, such as placing cables in lower bracket layers and adding fire-resistant partitions, based on the results from cable fire tests. These results provide primary full-scale experimental data and new insights into the distinct fire dynamics and thermal behavior of spreading fire sources in elongated, confined utility tunnels, offering valuable references for fire safety design and risk control in similar infrastructures.

在国内最大的公用隧道平台（100 m × 3 m × 3 m）上进行了一系列全尺寸火灾实验，研究了公用隧道火灾的火焰行为和热流演变。油田火灾和电缆火灾都可以在保持合理成本的情况下真实地复制火灾场景。对放热速率、通风条件、多火源、电缆布置等进行了综合分析。采用油池火灾模拟了早期电缆火灾的热输出，通风条件下的结果表明，由于热烟和反向气流之间的相互作用，峰值温度向下移动，纵向温度分布不对称。在电缆火灾中，热量释放是通过一层一层的点火模式积累起来的。火焰最初垂直传播，然后在足够的热积累后转变为纵向传播。根据这些发现，根据油池和电缆火灾情况下的通风测试分析，建议在火灾早期关闭通风并密封开口，以限制氧气供应。根据电缆火灾测试结果，优化电缆布局可以进一步减少垂直火焰蔓延，例如将电缆放置在较低的支架层并增加防火隔板。这些结果提供了第一手的全尺寸实验数据，并对细长密闭公用设施隧道中蔓延火源的独特火灾动力学和热行为有了新的认识，为类似基础设施的消防安全设计和风险控制提供了有价值的参考。

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引用次数: 0

Failure mechanism and stability control of fault induced by underground cavern excavation: insights from theoretical analysis and numerical modeling 地下洞室开挖断层破坏机制与稳定性控制：理论分析与数值模拟的启示

IF 7.4 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2026-01-02 DOI: 10.1016/j.tust.2025.107410

Guangzhe Tao , Zongqing Zhou , Bing Shao , Ning Liu , Chenglu Gao , Daosheng Zhang

The fault is one of the key factors that restricts the stability of surrounding rock masses in underground caverns. A comprehensive method including theoretical analysis, numerical simulation, and field investigation was conducted to investigate the failure mechanisms and control strategy of fault based on the underground cavern of the Kala (KL) hydropower station in Southwest China. Firstly, a mechanical failure criterion of fault failure was derived based on Anderson’s fault stress model and the Mohr-Coulomb criterion. Then, discrete element numerical software 3DEC was used to reveal the evolution process of fault slip and the influence mechanisms of system parameters, including shear stiffness, fault dip angle, and shear strength. Finally, a support and control strategy for fault stability was proposed based on the fault instability failure mechanism, which was implemented in the field. The results indicate that fault stability increases with increasing internal friction angle, cohesion, and minimum principal stress, but decreases with increasing maximum principal stress. The fault slip process exhibits three distinct successive stages: slow growth, rapid evolution, and stable equilibrium. Numerical results show that fault slip displacement follows a nonlinear trend with increasing dip angle (increasing first and then decreasing) and decreases significantly with higher shear stiffness and internal friction angle. A synergistic support strategy including “precision blasting + timely support” and “shotcrete + prestressed rockbolt + prestressed cables” was proposed based on the fault failure mechanism, which significantly reduces the risk of fault instability activation. Field monitoring indicates that the support scheme significantly reduces the tendency for fault instability, enhancing the stability of the surrounding rock.

断层是制约地下洞室围岩稳定性的关键因素之一。以西南Kala水电站地下洞室为例，采用理论分析、数值模拟和现场调查相结合的综合方法，对断层破坏机理和控制策略进行了研究。首先，基于Anderson断层应力模型和Mohr-Coulomb准则，推导了断层破坏的力学破坏准则；利用离散元数值软件3DEC揭示了断层滑动的演化过程以及剪切刚度、断层倾角、剪切强度等系统参数的影响机制。最后，基于故障失稳失效机理，提出了故障稳定的支持与控制策略，并在现场实施。结果表明：断层稳定性随内摩擦角、黏聚力和最小主应力的增大而增大，随最大主应力的增大而减小；断层滑动过程表现出三个明显的连续阶段：缓慢生长、快速演化和稳定平衡。数值结果表明，断层滑动位移随倾角的增大呈先增大后减小的非线性趋势，随剪切刚度和内摩擦角的增大而显著减小。根据断层破坏机理，提出了“精密爆破+及时支护”和“喷射混凝土+预应力锚杆+预应力索”的协同支护策略，显著降低了断层失稳激活的风险。现场监测结果表明，该支护方案明显降低了断层失稳的趋势，提高了围岩的稳定性。

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引用次数: 0