Underground Space最新文献

Combined active and passive support technology and its application for deformation control in large-section weakly cemented tunnel 主被动联合支护技术及其在大断面弱胶结隧道变形控制中的应用

IF 8.3 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2026-01-08 DOI: 10.1016/j.undsp.2025.10.007

Qing Ma , Wei Zhang , Xiaoli Liu , Weiqiang Xie , Ruosong Wang , Jinpeng Zhao

The development of large cross-section tunnels is an inevitable trend driven by the intensification of coal mining activities and advancements in mining equipment technology. However, the disturbance stress exerted by adjacent caverns has a more pronounced impact on weakly cemented rock strata in the vicinity of neighboring tunnels. To mitigate deformation in weakly cemented tunnels, grouting and the installation of long anchor cables were employed to reinforce the self-supporting capacity of the surrounding rock, thereby establishing an active support layer. Additionally, U-shaped steel frames combined with the subsequent application of flexible filling materials were utilized to aid the surrounding rock in mobilizing its self-supporting capacity, which resulted in the formation of a passive support layer. A layered collaborative control methodology integrating both active and passive support mechanisms was developed and implemented in engineering practice. The findings demonstrate that the vertical stress was alleviated after cavern excavation and was predominantly transferred toward the adjacent tunnel, with the influence zone extending approximately 7 to 12 times the tunnel height. Conversely, the horizontal stress is primarily dispersed laterally, affecting a region approximately 3 to 6 times the tunnel width. Following the infilling of pebbles between the U-shaped steel frame and the adjacent rock mass, the maximum compressive stress experienced by the U-shaped steel frame decreased by 50%. Additionally, the spatial extent of the maximum axial force was reduced by 65%, whereas the stresses within the rock bolts and cable bolts increased by 30% and 40%, respectively. Grouting reinforcement contributed to bonding and compaction effects on the delamination and fracturing of the roof strata, with the grout predominantly distributed within a range of 1.5 to 5 m from the central region of the roof. The research outcomes presented in this paper can provide valuable reference for a large-section weakly cemented tunnel.

随着煤炭开采活动的加剧和矿山设备技术的进步，大断面隧道的发展是必然趋势。而邻近洞室产生的扰动应力对邻近隧道附近弱胶结岩层的影响更为明显。为了缓解弱胶结隧道的变形，采用注浆和安装长锚索的方法来增强围岩的自支护能力，从而建立一个主动支护层。另外，利用u型钢框架配合后续柔性充填材料的应用，帮助围岩调动自支护能力，形成被动支护层。提出了一种结合主动和被动支撑机制的分层协同控制方法，并将其应用于工程实践。结果表明：洞室开挖后竖向应力得到缓解，并主要向邻近隧道转移，影响区延伸至隧道高度的7 ~ 12倍；相反，水平应力主要横向分散，影响区域约为隧道宽度的3 ~ 6倍。在u形钢框架与相邻岩体之间填充卵石后，u形钢框架承受的最大压应力降低了50%。此外，最大轴向力的空间范围减小了65%，而锚杆和锚索锚杆内的应力分别增加了30%和40%。注浆加固对顶板岩层起到粘结压实作用，使顶板岩层分层破裂，注浆主要分布在距顶板中心区1.5 ~ 5m范围内。本文的研究成果可为大断面弱胶结隧道的施工提供有价值的参考。

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引用次数: 0

Numerical simulation on progressive leakage in shield tunnel and corresponding mitigation 盾构隧道递进式泄漏数值模拟及治理

IF 8.3 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2026-01-07 DOI: 10.1016/j.undsp.2025.10.006

Tianqi Zhang, Bangguo He, Zhitong Chen, Gang Zheng, Chang Liu

Leakage disasters in shield tunnels frequently occur, leading to severe consequences such as tunnel collapse, road collapse, and building destruction. Since it is difficult to record the accident evolution process onsite, it is necessary to reproduce it through credible numerical simulations. However, traditional numerical methods face technical bottlenecks when simulating water–sand inrush in shield tunnels due to challenges such as large deformation analysis and fluid–structure coupling, making it difficult to simulate the process of disaster progression. To address this issue, a Coupled Eulerian–Lagrangian (CEL) method incorporating seepage analysis, referred to as the S-CEL method, was proposed to simulate the interaction between water, soil, and a shield tunnel during a disaster. A refined three-dimensional numerical model was developed using the S-CEL method to simulate the water–sand inrush process. The generation sequence of new leakage points at the segment joints and the mechanisms driving the progression of the disaster were revealed. New leakage points were progressively generated along the longitudinal direction of the tunnel. As the number of leakage rings increased, the amount of soil loss increased rapidly. This led to severe uneven settlement and dislocation deformation of the tunnel. A channel steel was introduced to reinforce the tunnel in the numerical simulation to mitigate or decelerate the progression of the leakage disaster. The connection method between the channel steel and tunnel segments was found to be pivotal to the strengthening effect. Employing only bolt anchoring showed limited efficacy, while enhancing the segment-steel interface with epoxy resin achieved much better performance in mitigating disaster progression.

盾构隧道渗漏灾害频繁发生，造成隧道坍塌、道路坍塌、建筑物破坏等严重后果。由于现场难以记录事故演变过程，有必要通过可靠的数值模拟再现事故演变过程。然而，传统数值方法在模拟盾构隧道水沙涌流时，由于存在大变形分析和流固耦合等难题，难以模拟灾害发展过程，面临技术瓶颈。为了解决这一问题，提出了一种结合渗流分析的耦合欧拉-拉格朗日（CEL）方法，即S-CEL方法，以模拟灾害期间水、土壤和盾构隧道之间的相互作用。采用S-CEL方法建立了精细化的三维数值模型来模拟水砂涌流过程。揭示了节理处新渗漏点的产生顺序及引发灾害发展的机理。新的渗漏点沿隧道纵向逐渐产生。随着渗漏环数的增加，土壤流失量迅速增加。这导致隧道严重的不均匀沉降和位错变形。在数值模拟中引入槽钢对隧道进行加固，以减轻或减缓渗漏灾害的发展。槽钢与隧道管片的连接方式对加固效果至关重要。仅采用锚杆锚固效果有限，而环氧树脂增强节段-钢界面的锚固效果更好。

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引用次数: 0

Reliability analysis of 1D estimation for TBM operational parameters TBM运行参数一维估计的可靠性分析

IF 8.3 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2026-01-05 DOI: 10.1016/j.undsp.2025.10.004

Oveis Farzay, Marilena Cardu

Accurate TBM performance estimation is essential for effective tunnel design and planning. This study introduces a one-dimensional (1D) estimation model that estimates thrust, torque, power, cutterhead speed, and tool count using only excavation diameter. The model was developed across four TBM types—open, single shield (SS), double shield (DS), and earth pressure balance (EPB)—to isolate the influence of diameter from other variables. Validation against existing models and a 52-case independent dataset confirmed strong correlations: torque scales with the cube of the excavation diameter (R² = 0.89 for EPB), power grows faster than linearly (R² = 0.83 for EPB), thrust increases supra-linearly (R² = 0.79 for EPB), and cutterhead speed decreases with diameter (R² = 0.87 for open TBM). Tool count grows proportionally. A reliability matrix compares model accuracy and data support, aiding selection based on both fitness and robustness. This 1D model offers fast, consistent estimates for early-stage assessments. While it excludes detailed geological input, it is suited for feasibility studies and preliminary design. Future work will incorporate additional ground and machine parameters and extend validation across a broader range of tunneling conditions to enhance generalizability.

准确的隧道掘进机性能评估对有效的隧道设计和规划至关重要。本研究引入了一维（1D）估算模型，该模型仅使用开挖直径估算推力、扭矩、功率、刀盘速度和刀具数量。该模型建立在四种掘进机类型（开式、单盾构（SS）、双盾构（DS）和土压平衡（EPB））上，以隔离直径对其他变量的影响。对现有模型和52例独立数据集的验证证实了强相关性：扭矩与开挖直径的立方呈正相关（对于EPB， R2 = 0.89），功率增长快于线性（对于EPB， R2 = 0.83），推力增加超线性（对于EPB， R2 = 0.79），刀盘速度随直径减小（对于开式TBM， R2 = 0.87）。工具数量按比例增长。可靠性矩阵比较模型的准确性和数据支持度，帮助基于适应度和鲁棒性的选择。这种一维模型为早期评估提供了快速、一致的估计。虽然它不包括详细的地质输入，但它适合于可行性研究和初步设计。未来的工作将纳入更多的地面和机器参数，并在更广泛的隧道条件下扩展验证，以提高通用性。

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引用次数: 0

Effects of shield tunnelling parameters on the long-term settlement of piled buildings in soft ground 软土地基中盾构施工参数对桩基建筑长期沉降的影响

IF 8.3 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2026-01-05 DOI: 10.1016/j.undsp.2025.10.003

Ruikun Wang , Gang Zheng , Huayang Lei , Xuesong Cheng , Eng-Choon Leong , Yetao Ji

This study investigated the long-term settlement behaviour of piled buildings induced by shield tunnelling in soft ground conditions within urban environments. By integrating a detailed case study with advanced numerical modelling techniques, this study provided a nuanced understanding of the interactions between tunnel construction and existing pile foundations. Central to the investigation is the role of soil consolidation, which significantly contributes to the settlement of piled buildings. To address this, this study emphasizes the critical need for the precise calibration of tunnelling parameters such as face pressure and grouting pressures. These parameters are meticulously controlled to mitigate the adverse effects on nearby piled buildings, ensuring their stability and integrity. It is established that an optimal face pressure, set at 90% of the lateral earth pressure, consistently minimizes the settlement of piled buildings, primarily due to the minimal reduction in the pile toe resistance observed near the tunnel. Similarly, the ideal grouting pressure was identified to be within the range of 120%–160% of the vertical earth pressure, with the smallest building settlement and decrease in pile toe resistance observed at a grouting pressure of 150% of the overburden pressure. This finding elucidates the load transfer mechanism within piled buildings. This study further demonstrated that the settlement induced by the second tunnel excavation is smaller than that caused by the first tunnel excavation owing to the sheltering effects of the adjacent first tunnel and pile foundations. During the consolidation phase following tunnel excavation, the settlement caused by the second tunnel is smaller than that caused by the first tunnel, which is attributed to the dissipation of the negative excess pore pressure around the first tunnel, leading to soil volume expansion. These insights not only validate the effectiveness of the numerical model but also contribute significantly to the field of geotechnical engineering by providing actionable guidelines for future tunnelling projects.

本文研究了城市软土地基条件下盾构隧道施工引起的桩基建筑长期沉降行为。通过将详细的案例研究与先进的数值模拟技术相结合，本研究提供了对隧道施工与现有桩基之间相互作用的细致理解。调查的中心是土壤固结的作用，这对堆积的建筑物的沉降有很大的贡献。为了解决这一问题，本研究强调了对掘进参数（如工作面压力和注浆压力）进行精确校准的迫切需要。这些参数经过精心控制，以减轻对附近堆积的建筑物的不利影响，确保它们的稳定性和完整性。结果表明，最优工作面压力为侧土压力的90%时，可使已桩建筑物的沉降始终最小，这主要是由于在隧道附近观察到的桩脚阻力减小最小。同样，理想注浆压力为竖向土压力的120% ~ 160%，注浆压力为覆盖层压力的150%时，建筑沉降最小，桩脚阻力减小最小。这一发现阐明了桩内荷载传递机制。研究进一步表明，由于相邻第一隧道和桩基的庇护作用，第二隧道开挖引起的沉降小于第一隧道开挖引起的沉降。在隧道开挖后固结阶段，第二隧道引起的沉降小于第一隧道引起的沉降，这是由于第一隧道周围负超孔隙压力的消散导致土体积膨胀。这些见解不仅验证了数值模型的有效性，而且通过为未来的隧道工程提供可操作的指导方针，对岩土工程领域做出了重大贡献。

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引用次数: 0

Degradation mechanism of microstructure of residual coal pillars during highly mineralized mine-water storage in coal mine goaf 煤矿采空区高矿化储水过程中残余煤柱微结构降解机理

IF 8.3 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2025-12-24 DOI: 10.1016/j.undsp.2025.10.001

Hao Liu , Zenghui Zhao , Qing Ma , Xiaoli Liu , Longjie Zhu

Driven by the “dual carbon” strategy, the functionality of coal mine underground reservoirs is transitioning toward multimedia collaborative storage, such as CO₂ geological sequestration and strategic energy reserves. The microscopic structures of the coal pillar dams, which are subjected to mining-induced damage and long-term infiltration erosion by highly mineralized mine water, continuously deteriorate over time, posing significant risks to the long-term safety and stability of the reservoirs. This study, based on the Lingxin Coal Mine Underground Reservoir Demonstration Project, employs a multi-technique characterization approach including X-ray diffraction (XRD), scanning electron microscope, nuclear magnetic resonance, and computed tomography to systematically reveal the multiscale collaborative erosion mechanisms of highly mineralized mine water on the mineral composition, crystal structure, and pore development of coal pillar dams. The results indicate: (1) significant concentration-dependent deterioration of mineral composition and crystal structure; kaolinite hydrolysis had a weakening effect on XRD peaks while quartz remained inert; (2) initiation of progressive microstructural damage at boundaries via dissolution/loosening; this damage advanced through layered mineral delamination and pore development (evidenced by NMR T₂ broadening), resulting in irreversible void formation with chloride precipitation; (3) formation of pore-throat halite crystals, primarily due to chloride ions (Cl^–); these crystals propagated microfractures through salt-expansion stress, establishing a cyclic dissolution–migration–crystallization–cracking process; (4) triggering of accelerated deterioration of the coal matrix owing to prolonged retention; this induced time- and concentration-dependent expansion and interconnection of pore-fracture networks, resulting in geomechanical deterioration.

在“双碳”战略的推动下，煤矿地下储层的功能正在向CO2地质封存、战略能源储备等多媒体协同存储功能过渡。煤柱坝由于受到采动破坏和高矿化矿井水的长期入渗侵蚀，其微观结构随着时间的推移不断恶化，对水库的长期安全稳定构成重大威胁。本研究以灵新煤矿地下水库示范工程为依托，采用x射线衍射（XRD）、扫描电镜、核磁共振、计算机断层扫描等多技术表征方法，系统揭示了高矿化矿水对煤柱坝矿物组成、晶体结构、孔隙发育的多尺度协同侵蚀机制。结果表明：(1)矿物组成和晶体结构随浓度显著恶化；高岭石水解对XRD峰有减弱作用，而石英保持惰性；(2)通过溶解/松动在边界处引发渐进的显微组织损伤；这种破坏通过层状矿物分层和孔隙发育进行（核磁共振T2展宽证明），导致氯离子沉淀形成不可逆孔隙；(3)形成孔喉岩盐晶体，主要是由于氯离子（Cl -）；这些晶体通过盐膨胀应力扩展微裂缝，形成了溶蚀-迁移-结晶-破裂的循环过程；(4)长时间滞留导致煤基体加速变质；这导致了随时间和浓度变化的孔隙-裂缝网络的扩展和连接，从而导致地质力学恶化。

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引用次数: 0

GPR-HIDiff: A diffusion-based model for horizontal interference suppression in urban underground detection radar profiles GPR-HIDiff：基于扩散的城市地下探测雷达剖面水平干扰抑制模型

IF 8.3 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2025-12-13 DOI: 10.1016/j.undsp.2025.08.002

Xiaosong Tang , Feng Yang , Xu Qiao , Jialin Liu , Haitao Zuo , Liang Gao , Jianshe Zhao , Suping Peng

Automated subsurface utility detection systems in construction rely heavily on the quality of ground-penetrating radar (GPR) profiles, which are often degraded by high-amplitude horizontal interference. Existing low-rank decomposition methods lack the intelligence and flexibility required for multi-site data processing and involve labor-intensive parameter tuning, impeding their integration into intelligent construction workflows. To address these challenges, this paper proposes a horizontal interference suppression algorithm based on a diffusion model, termed GPR-HIDiff. The proposed model replaces conventional sequential convolutional operators with ResBlocks throughout the encoder, intermediate layer, and decoder of the UNet architecture, enhancing training stability. Lightweight agent attention modules are embedded between ResBlocks at each level to improve global information modeling capability. A spatial attention mechanism is deployed between the encoder and decoder to achieve adaptive spatial feature optimization. Furthermore, the forward diffusion phase adopts a cos

θ

schedule-based strategy to ensure a smooth temporal variation of noise variance. A standardized dataset comprising real-world measured samples and finite difference time domain simulation samples of urban road models has also been constructed. The effectiveness of the hybrid dataset, the introduced modules, the robustness analysis, and the cos

θ

schedule is validated through training with single/mixed datasets, ablation studies, evaluation of metric variations before and after the introduction of different noise levels, and comparative experiments with constant, linear, and cos

θ

schedules. Experimental results demonstrate that GPR-HIDiff significantly outperforms both traditional methods and state-of-the-art deep learning models on both simulated and real-world test samples. It effectively suppresses horizontal artifacts, preserves target hyperbolic contours, and avoids excessive reduction of target scattering, showcasing its exceptional performance. This method provides a powerful algorithmic foundation for high-resolution GPR imaging and target detection.

建设中的自动化地下公用事业探测系统在很大程度上依赖于探地雷达（GPR）剖面的质量，而这些剖面经常受到高振幅水平干扰的影响。现有的低秩分解方法缺乏多站点数据处理所需的智能和灵活性，并且涉及劳动密集型的参数调整，阻碍了它们与智能施工工作流的集成。为了解决这些挑战，本文提出了一种基于扩散模型的水平干扰抑制算法，称为GPR-HIDiff。该模型在UNet架构的编码器、中间层和解码器中使用ResBlocks取代传统的顺序卷积算子，增强了训练的稳定性。在每个级别的ResBlocks之间嵌入轻量级代理关注模块，以提高全局信息建模能力。在编码器和解码器之间部署空间注意机制，实现自适应空间特征优化。此外，前向扩散阶段采用基于成本θ调度的策略，以确保噪声方差的平滑时间变化。构建了由城市道路模型的实际测量样本和有限差分时域模拟样本组成的标准化数据集。混合数据集、引入的模块、鲁棒性分析和成本θ计划的有效性通过单个/混合数据集的训练、烧蚀研究、引入不同噪声水平前后度量变化的评估以及恒定、线性和成本θ计划的比较实验来验证。实验结果表明，GPR-HIDiff在模拟和现实世界的测试样本上都明显优于传统方法和最先进的深度学习模型。它有效地抑制了水平伪影，保留了目标的双曲轮廓，避免了目标散射的过度减少，显示出其优异的性能。该方法为高分辨率探地雷达成像和目标检测提供了强大的算法基础。

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引用次数: 0

A DEA–based efficiency evaluation method for metro-led urban underground public space 基于dea的地铁主导城市地下公共空间效率评价方法

IF 8.3 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2025-12-13 DOI: 10.1016/j.undsp.2025.02.013

Zi-Yun Zhang, Fang-Le Peng, Chen-Xiao Ma, Yong-Kang Qiao

Despite the thriving development of metro-led urban underground public space (UUPS) and its significant benefits and costs, there remains a critical research gap in understanding and evaluating its efficiency. This paper intends to improve the post-evaluation system of metro-led UUPS by proposing an efficiency evaluation framework based on data envelopment analysis. The public and the private sectors are taken as different coexisting decision-makers, and a pair of linear programming is built accordingly (with different assignments of discretionary and non-discretionary inputs) for each decision-making unit. The directional vector is calculated based on CRITIC weights to model the searching process of referential cases in terms of urban renewal. The empirical study of twenty metro-led UUPSs in central Shanghai reveals that (1) the proposed evaluation framework is feasible and discriminative, (2) the efficient form of metro-led UUPS in Shanghai is mainly limited to a compact pattern with a low proportion of pure public space, (3) the essential solution to promote efficiencies is closer cooperation between different parties, and (4) efficiency evaluation is crucial to avoiding the “the-more-the-better” type of development. The findings of this study are expected to shed light on the future planning and operation of metro-led UUPS.

尽管地铁主导的城市地下公共空间（UUPS）蓬勃发展，其效益和成本显著，但在认识和评估其效率方面仍存在重大的研究空白。本文提出了一种基于数据包络分析的效率评价框架，旨在完善城域ups的后评价体系。将公共部门和私营部门视为不同的共存决策者，并相应地为每个决策单元构建一对线性规划（自由裁量和非自由裁量输入的分配不同）。基于CRITIC权重计算方向向量，模拟城市更新参考案例的搜索过程。通过对上海市中心城区20个地铁主导UUPS的实证研究表明：(1)本文提出的评价框架具有可行性和判别性；(2)上海地铁主导UUPS的效率形态主要局限于紧凑格局，纯公共空间比例较低；(3)提高效率的根本解决方案是各方更密切的合作；(4)效率评价是避免“越多越好”型发展的关键。这项研究的结果有望为地铁主导的UUPS的未来规划和运营提供启示。

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引用次数: 0

Dynamic response of deep tunnel subjected to contour blasting-unloading considering internal free surface radius 考虑内自由面半径的深埋隧道轮廓爆破卸载动力响应

IF 8.3 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2025-12-06 DOI: 10.1016/j.undsp.2025.09.005

Siyu Peng, Xibing Li, Lisha Liang, Jingyao Gao

The dynamic stress response of the surrounding rock in deep tunnels during contour blasting is first derived using elastic statics and dynamics theory alongside Fourier transform methods. This solution uniquely accounts for the effects of lateral stress coefficient, blasting loading, two-dimensional unloading, and the redistribution of static stress fields induced by internal free surfaces. Discrete element numerical simulations are also performed and cross-validated with the theoretical model. The study analyzes and discusses the effects of in-situ stress levels, lateral stress coefficients

k

, and internal radius ratio

{\tilde{r}}_{0}

(ratio of internal free surface radius to tunnel radius) on the failure characteristics and mechanisms of surrounding rocks. The results indicate that increasing

{\tilde{r}}_{0}

can reduce the unloading amplitude, thereby decreasing the dynamic circumferential compressive stress and circumferential cracking induced by unloading, especially under high in-situ stress. Under low stress levels, the maximum dynamic radial compressive stress during blasting decreases, reducing radial compression-shear failure. Simultaneously, the dynamic circumferential tensile stress is also reduced, thereby minimizing blasting-induced radial fractures. However, under extreme lateral stress conditions (k < 0.2), adjusting

{\tilde{r}}_{0}

cannot cause the circumferential stress to exceed the radial stress at the tunnel contour along the maximum principal stress direction. As a result, an ideal contour blasting effect cannot be achieved, and failure continues to propagate radially. In conclusion, the derived dynamic blasting-unloading stress response, in relation to the internal radius ratio, provides theoretical analysis tools for understanding the failure characteristics and mechanisms of surrounding rock during contour blasting, serving as a foundation for optimizing blasting and support design.

首先利用弹性静力学和动力学理论，结合傅立叶变换方法，推导了深埋巷道轮廓爆破过程中围岩的动应力响应。该解决方案独特地考虑了侧向应力系数、爆破载荷、二维卸载以及内部自由表面引起的静态应力场重分布的影响。本文还进行了离散元数值模拟，并与理论模型进行了交叉验证。研究分析和讨论了地应力水平、侧向应力系数k和内半径比r ~ 0（内自由面半径与巷道半径之比）对围岩破坏特征和破坏机制的影响。结果表明，增大r ~ 0可以减小卸荷幅值，从而减小动周向压应力和卸荷引起的周向开裂，特别是在高地应力条件下。在低应力水平下，爆破过程中最大动态径向压应力减小，减少了径向压剪破坏。同时，动态周向拉应力也降低了，从而最大限度地减少了爆破引起的径向裂缝。然而，在极端侧向应力条件下（k < 0.2），调整r ~ 0不能使沿最大主应力方向隧道轮廓处的周向应力超过径向应力。因此，不能达到理想的轮廓爆破效果，破坏继续径向传播。综上所述，推导出的与内半径比相关的动爆卸荷应力响应，为了解轮廓爆破过程中围岩破坏特征和破坏机制提供了理论分析工具，为优化爆破和支护设计提供了依据。

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引用次数: 0

Carbon emission mechanism and influence of design-oriented railway tunnel engineering 以设计为导向的铁路隧道工程碳排放机理及影响

IF 8.3 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2025-12-04 DOI: 10.1016/j.undsp.2025.09.004

Yajuan Li, Xueying Bao

Tunnels are critical transportation infrastructure, with >80% of their lifecycle carbon emissions from the design phase. Therefore, low-carbon design is a pathway to achieving “zero carbon” goals. However, multi-source and heterogeneous design information creates challenges because of tunnel carbon emission data silos. This study proposes a carbon emissions-structure-design framework with a multi-layered integrated structure for tunnel carbon footprint assessment, clarifying the relationships among design parameters, structural characteristics, and carbon emissions. Additionally, a design structure matrix-carbon footprint model is established to analyze the relationships between low-carbon design elements (LDEs) and the lifecycle carbon footprint. A model is developed to examine the nonlinear mechanisms by which LDEs affect carbon emissions. Case studies indicate that carbon emissions during the construction phase primarily arise from tunnel boring machine excavation, slag transportation, shotcreting, and tunnel lining. They are significantly influenced by LDEs, such as the surrounding rock grade, tunnel radius, advance rate, and slope, which exhibit threshold effects. In the operational phase, carbon emissions are dominated by train traction energy consumption, which increases with speed and decreases with radius. This is in contrast to the construction phase, where larger radii lead to higher emissions. This study integrates tunnel design parameters with lifecycle carbon emissions to overcome the limitations of traditional segmented approaches. The findings provide a decision-support framework for source-level emission reduction during the design phase, enabling engineers to predict carbon emissions for parameter combinations and offer a new strategy for achieving carbon neutrality in transportation infrastructure.

隧道是关键的交通基础设施，其生命周期中80%的碳排放来自设计阶段。因此，低碳设计是实现“零碳”目标的途径。然而，由于隧道碳排放数据孤岛，多源和异构的设计信息带来了挑战。本研究提出了一种多层一体化结构的隧道碳足迹碳排放-结构-设计框架，明确了设计参数、结构特征与碳排放之间的关系。建立设计结构矩阵-碳足迹模型，分析低碳设计元素与全生命周期碳足迹之间的关系。本文建立了一个模型来检验低密度发光二极管影响碳排放的非线性机制。实例研究表明，施工阶段的碳排放主要来自隧道掘进机开挖、输渣、喷射和隧道衬砌。围岩坡度、隧道半径、推进速度、坡度等因素对巷道围岩的影响显著，表现出阈值效应。在运行阶段，碳排放以列车牵引能耗为主，随速度增加而增加，随半径减小。这与施工阶段形成对比，在施工阶段，更大的半径导致更高的排放。该研究将隧道设计参数与生命周期碳排放相结合，克服了传统分段方法的局限性。研究结果为设计阶段的源头减排提供了决策支持框架，使工程师能够预测参数组合的碳排放，并为实现交通基础设施的碳中和提供了新的策略。

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引用次数: 0

Experimental study on rock damage and failure induced by multi-source dynamic disturbances 多源动力扰动对岩石损伤破坏的实验研究

IF 8.3 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2025-12-04 DOI: 10.1016/j.undsp.2025.09.003

Han-Yi Liu, Ben-Guo He, Jia-Hua Guan, Hong-Yuan Fu

Research into the mechanical behaviour of rock surrounding the deep-buried tunnel under multi-source dynamic disturbance is key to the safety of underground engineering operations. Based on a dynamic true-triaxial testing apparatus, the present study examined the mechanical behaviours and fracture mechanisms of deep granite under the coupled effects of intermediate-frequency dynamic disturbance (f = 300 Hz) and low-frequency dynamic disturbance (f = 5–20 Hz). Intermediate-frequency dynamic disturbance markedly initiates the genesis of tensile micro-cracks within rock, while low-frequency dynamic disturbance exacerbates the propagation and interconnection of cracks, ultimately leading to the formation of a tensile-shear mixed failure mode. The severity of the influence of intermediate-frequency disturbance on the peak strength of rock is the initial crack compaction σ_cc (decreased by 8.1%), the damage stress σ_cd (decreased by 6.4%), and the crack initiation stress σ_ci (decreased by 4.7%) under different disturbance timings. This changes the characteristic stress of the rock and significantly decreases its brittleness index. Meanwhile, the low-frequency f of weak disturbance significantly affects the failure mode and peak strength of the rock. The peak strength σ_p exhibits U-shaped variation, with the maximum decrease reaching 15 MPa, which indicates the presence of a resonance effect between the external disturbance and the natural frequency of the rock. The timing of intermediate-frequency disturbance alters the natural frequency of the rock. Analysis of the fracture surface shows that cracks induced by intermediate-frequency disturbance primarily propagate along the σ₁-direction, while low-frequency disturbance promotes propagation of shearing cracks along the σ₃-direction. Brittle failure occurs due to the through-going shearing cracks. The results further reveal the synergistic mechanism of action of multi-source dynamic disturbance on rock failure, indicating that the coupled effects of multi-source dynamic disturbances significantly increase the risk of brittle failure in the rock mass.

多源动力扰动作用下深埋隧道围岩的力学行为研究是影响地下工程安全运行的关键。基于动态真三轴试验装置，研究了中频动态扰动（f = 300 Hz）和低频动态扰动（f = 5 ~ 20 Hz）耦合作用下深部花岗岩的力学行为和断裂机制。中频动力扰动显著地启动了岩石内部拉伸微裂纹的形成，低频动力扰动则加剧了裂缝的扩展和连接，最终导致拉剪混合破坏模式的形成。不同干扰时间中频扰动对岩石峰值强度的影响程度分别为初始裂纹压实σcc（减小8.1%）、损伤应力σcd（减小6.4%）和裂纹起裂应力σci（减小4.7%）。这改变了岩石的特征应力，显著降低了岩石的脆性指数。同时，弱扰动的低频f显著影响岩石的破坏模式和峰值强度。峰值强度σp呈u型变化，最大降幅达15 MPa，表明外部扰动与岩石固有频率之间存在共振效应。中频扰动的发生时间改变了岩石的固有频率。断口形貌分析表明，中频扰动诱发的裂纹主要沿σ1方向扩展，低频扰动诱发的剪切裂纹主要沿σ3方向扩展。脆性破坏是由贯通的剪切裂纹引起的。结果进一步揭示了多源动力扰动对岩石破坏的协同作用机制，表明多源动力扰动的耦合作用显著增加了岩体脆性破坏的风险。

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引用次数: 0