Underground Space最新文献_第9页

Intelligent optimization of TBM cutter spacing and FDEM-based investigation of rock breakage considering brittleness TBM刀距智能优化及基于fdem的脆性破岩研究

IF 8.2 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2025-08-01 Epub Date: 2025-07-01 DOI: 10.1016/j.undsp.2025.02.011

Youlin Qin , Li Yu , Mingnian Wang , Zhaohui Chen , Hong Jin , Mingyang Yu , Songshen Wang

Cutter spacing is a key factor influencing the efficiency of TBM operations. Meanwhile, rock brittleness, as a critical indicator of rock fracture, significantly influences fragmentation behavior and rock-breaking efficiency. This study investigates the influence of rock brittleness on rock-breaking through numerical penetration experiments based on the hybrid finite-discrete element method (FDEM) and proposes four intelligent hybrid models to optimize cutter spacing. The results show that as the rock brittleness index (BI) increases from 4.731 to 32.588, the count, depth, width, and proportion of tensile cracks increase, and crack propagation shifts from horizontal to oblique orientations. Moderate cutter spacing (90–110 mm) is optimal for generating tensile cracks. The rock-breaking force increases significantly with higher BI; for instance, at 80 mm spacing, the maximum force for rock with a BI of 13.134 is 5.51 times that for rock with a BI of 4.731. The influence of BI on cutter work and specific energy (SE) is more substantial than the effect of cutter spacing. As BI increases, both cutter work and SE rise considerably. Among the proposed models, the particle swarm optimization and extreme gradient boosting (PSO-XGBoost) model demonstrates the highest performance, achieving an R² of 0.994, VAF of 99.418%, RMSE of 0.987, and MAPE of 5.217% on the test datasets. An optimization method for cutter spacing is proposed based on this model.

刀距是影响掘进机作业效率的关键因素。同时，岩石脆性作为岩石破裂的重要指标，对岩石破碎行为和破岩效率有显著影响。基于有限-离散元混合方法（FDEM），通过数值侵彻实验研究岩石脆性对破岩的影响，提出了四种智能混合模型来优化刀距。结果表明：随着岩石脆性指数（BI）从4.731增加到32.588，拉伸裂纹的数量、深度、宽度和比例均有所增加，裂纹扩展方向由水平向斜向转变；适度的刀具间距（90-110毫米）是产生拉伸裂纹的最佳选择。随着BI的增大，破岩力显著增大；例如，在80 mm间距下，BI为13.134的岩石的最大受力是BI为4.731的岩石的5.51倍。BI对刀具功和比能（SE）的影响大于刀具间距的影响。随着BI的增加，切削功和SE都显著增加。其中，粒子群优化和极端梯度增强（PSO-XGBoost）模型的性能最好，在测试数据集上的R2为0.994，VAF为99.418%，RMSE为0.987，MAPE为5.217%。在此基础上提出了一种刀具间距优化方法。

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引用次数: 0

Hygrothermal behavior of energy diaphragm wall and the induced heat and moisture interaction with adjacent underground space 能量连续墙的热湿特性及其与邻近地下空间的热湿相互作用

IF 8.2 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2025-08-01 Epub Date: 2025-04-23 DOI: 10.1016/j.undsp.2025.01.006

Xu Zhou , Xiaoling Cao , Ziyu Leng , Chao Zeng , Yanping Yuan , Shady Attia

In the field of design and application of the energy diaphragm wall (EDW), plenty of research was focused on thermal performances and induced mechanical behaviors. The coupled heat and moisture transfer process and the induced impact on the adjacent underground space were lack of attention, which is inevitable due to the high humidity of the surroundings. Therefore, in this paper, a numerical model taking the gradient of the temperature and relative humidity as the driving potential was established to investigate the characteristics of the coupled heat and moisture transfer in the EDW. Firstly, the behavior of the coupled heat and moisture transfer in the summer and winter was investigated separately, and it was compared with the pure thermal model. Results show that the colder the wall surface, the more humid it is. The heat flux is enlarged by the operation of the EDW. Moreover, the heat flux will be underestimated by more than 3.43% in the heat extraction season and by more than 3.90% in the heat injection case if the moisture transfer is not considered. The following long-running investigations have revealed that the latent flux reaches its maximum and minimum value in transition seasons, with a value that is ten times smaller than that of the sensible heat flux. The sensible heat flux reaches 18.7 W/m² in summer, while in winter it is −27.4 W/m². The peak latent heat flux is reduced by 14.7% as a result of the combined effect of changes in surface temperature and humidity, due to the operation of the EDW. Additionally, the magnitude of these fluxes is affected by the indoor conditions (temperature and relative humidity of the indoor air) and the operating temperature of EDW. Therefore, an orthogonal test is performed to evaluate how much the discrepancies are induced by variations in those parameters. The impact of each parameter varies across the seasons (summer, transition season, and winter). However, the indoor relative humidity has a more significant influence on the water vapor flux in all the seasons. This paper provided details about the coupled heat and moisture transfer process in the EDW. Moreover, it attempts to raise an issue about the impact on the hygrothermal load induced by the heat and moisture flux through the wall surface when applying EDW in underground engineering.

在节能连续墙的设计和应用领域，大量的研究集中在热性能和诱导力学行为上。热湿耦合传递过程及其对邻近地下空间的影响缺乏重视，这是周边高湿环境不可避免的。为此，本文建立了以温度和相对湿度梯度为驱动势的数值模型，研究了电火花放电室内热湿耦合传递的特征。首先，分别研究了夏季和冬季的热湿耦合传递特性，并与纯热模型进行了比较。结果表明，壁面越冷，壁面湿度越大。EDW的运行使热流密度增大。在不考虑水分传递的情况下，抽热季节的热流密度被低估了3.43%以上，注热季节的热流密度被低估了3.90%以上。随后的长期调查表明，潜热通量在过渡季节达到最大值和最小值，其值比感热通量小10倍。夏季感热通量为18.7 W/m2，冬季感热通量为- 27.4 W/m2。由于EDW的运行，地表温度和湿度变化的综合影响使潜热通量峰值降低了14.7%。此外，这些通量的大小受室内条件（室内空气的温度和相对湿度）和EDW的工作温度的影响。因此，进行正交试验以评估由这些参数的变化引起的差异。每个参数的影响在不同的季节（夏季、过渡季节和冬季）有所不同。而室内相对湿度对各季节水汽通量的影响更为显著。本文详细介绍了电炉内的热湿耦合传递过程。此外，还试图提出在地下工程中应用电火花堆焊时，墙体表面的热湿通量对湿热负荷的影响问题。

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引用次数: 0

Monitoring and strengthening of prestressed concrete cylinder pipes based on distributed acoustic sensing and iron-based shape memory alloys 基于分布声传感和铁基形状记忆合金的预应力混凝土圆柱形管监测与加固

IF 8.2 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2025-08-01 Epub Date: 2025-04-27 DOI: 10.1016/j.undsp.2025.01.007

Jianghao Ji , Hong Zhu , Zhiqiang Dong , Yijie Pan , Shitong Hou , Liping Cui

This paper proposes an integrated system for monitoring and strengthening the prestressed concrete cylinder pipe (PCCP) with broken wires, which is based on distributed acoustic sensing (DAS) and self-prestressing iron-based shape memory alloy (Fe-SMA). This system was evaluated in a full-scale study on a PCCP with an inner diameter of 1400 mm and a length of 6000 mm. Firstly, the wire breakage signals were monitored by the DAS system. After that, the PCCP with broken wires were strengthened by Fe-SMA bars, and the mechanical properties were tested. The parameters such as different wire breakage ratios and self-prestressing degrees of Fe-SMA bars were also studied. The results show that the DAS system can identify the time and location of wire breakage; the wire breakage signal is characterized by high amplitude and short duration. After being prestressed with Fe-SMA bars, both the width and length of the main crack, as well as the strains in the concrete, mortar coating, and prestressed steel wires, significantly decreased. Additionally, the higher activation temperature of Fe-SMA bars can effectively offset the negative impact caused by the wire breakage development of PCCP. Combined Fe-SMA with the DAS monitoring system, it enables precise positioning and efficient strengthening of in-service PCCP with broken wires.

提出了一种基于分布式声传感（DAS）和自预应力铁基形状记忆合金（Fe-SMA）的预应力混凝土圆柱管断丝监测与加固综合系统。该系统在内径为1400 mm，长度为6000 mm的PCCP上进行了全面研究。首先，利用DAS系统对断线信号进行监测。然后用Fe-SMA棒对断线PCCP进行强化，并对其力学性能进行测试。并对不同断丝率和自预应力程度等参数进行了研究。结果表明，该系统能够准确识别断线的时间和位置；断线信号具有振幅大、持续时间短的特点。经Fe-SMA钢筋预应力后，主裂缝的宽度和长度以及混凝土、砂浆涂层和预应力钢丝中的应变均显著减小。此外，Fe-SMA棒的较高活化温度可以有效抵消PCCP断丝发展带来的负面影响。将Fe-SMA与DAS监测系统相结合，可以对断线的在用PCCP进行精确定位和有效强化。

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引用次数: 0

Time-dependent behaviors of energy piles embedded in multilayered saturated transversely isotropic soils 多层饱和横向各向同性土中埋置能量桩时变性研究

IF 8.2 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2025-08-01 Epub Date: 2024-11-29 DOI: 10.1016/j.undsp.2024.07.009

Yongzhi Zhao, Zhenming Shi, Zhiyong Ai

This paper presents a solution for the time-dependent behaviors of energy piles embedded in transversely isotropic soils, which considers the mechanical and thermal consolidation. By using the transformed differential quadrature method, kernel functions of coupled thermal-hydro-mechanical solution on the soil-energy pile interface are obtained and the boundary integration is conducted. Then, the energy pile is discretized into finite elements. After introducing the displacement coordination and boundary conditions, matrix equations to reflect the interaction between the surrounding soils and energy piles are formulated and solved. Since the consolidation is considered, the solution for energy pile behaviors with time including displacements and thermal stresses are achieved. Computational results are compared with data of existed literatures and field tests to validate the theory in this study. Finally, numerical examples are conducted to discuss the effects of transverse isotropy of soils, consolidation process and the length-diameter ratio of the energy pile.

本文提出了一种考虑力学固结和热固结的横向各向同性土中能量桩的时效特性求解方法。利用变换微分正交法，得到了土-能桩界面上热-水-力耦合解的核函数，并进行了边界积分。然后，将能量桩离散为有限元。在引入位移协调和边界条件后，建立并求解了反映周围土体与能量桩相互作用的矩阵方程。由于考虑固结，得到了能量桩位移和热应力随时间变化的解。计算结果与已有文献和现场试验数据进行了比较，验证了本文的理论。最后，通过数值算例讨论了土体横向各向同性、固结过程和能量桩长径比对能量桩稳定性的影响。

引用次数: 0

Passive instability of longitudinally inclined shallowly-buried shield tunnel using physical model tests and DEM simulations 纵向倾斜浅埋盾构隧道被动失稳物理模型试验与DEM模拟

IF 8.2 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2025-08-01 Epub Date: 2025-05-30 DOI: 10.1016/j.undsp.2025.02.006

Zhiwang Lu , Youlin Ye , Pengpeng Ni , Zijie Qian , Ben Niu , Shijian Shang

Stability of tunnel face is crucial, but previous studies often overlooked the effect of longitudinal tunnel inclination, leading to inaccurate stability assessments. In this study, nine groups of 1g model tests were conducted to study the influence of longitudinal tunnel inclination on passive limit support pressure and passive failure mode of soil in front of the tunnel face under shallow burial conditions (i.e., cover depth ratio of 0.25, 0.50 and 0.75) in a sand stratum. In addition, discrete element method (DEM) analyses at the same scale were established and calibrated against the model test results. Accordingly, the micromechanical information of soil was derived from a microscopic perspective. The results indicate that upon the passive instability of tunnel face, the soil in front of the tunnel face firstly moved approximately perpendicular to the tunnel face, and then it deflected. The instability area of soil in front of the tunnel face increased with the decrease of longitudinal inclination, when the tunnel cover depth was fixed. Furthermore, microscopic analyses indicate that the longitudinal inclination could significantly affect the soil contact orientation in front of the tunnel face. This was more likely to cause the failure zone to rotate.

隧道工作面稳定性至关重要，但以往的研究往往忽略了隧道纵向倾斜的影响，导致稳定性评估不准确。本研究通过9组1g模型试验，研究浅埋条件下（覆盖深度比分别为0.25、0.50和0.75）沙层中隧道纵向倾斜对隧道前方土体被动极限支撑压力和被动破坏模式的影响。此外，建立了相同尺度下的离散元法（DEM）分析，并根据模型试验结果进行了校正。因此，从微观角度获得了土壤的微观力学信息。结果表明：在隧道工作面被动失稳时，隧道工作面前方土体先近似垂直于工作面移动，然后发生偏转；当隧道覆盖深度一定时，巷道前方土体失稳面积随着纵向倾斜度的减小而增大。细观分析表明，纵向倾角对巷道前方土体接触方向有显著影响。这更有可能导致故障区旋转。

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引用次数: 0

Introduction to the second Jeme Tien Yow Lecture 第二次詹天佑讲座简介

IF 8.2 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2025-08-01 Epub Date: 2025-05-03 DOI: 10.1016/j.undsp.2025.04.001

Hehua Zhu

引用次数: 0

Optimizing microseismic sensor networks in underground space using Cramér–Rao Lower Bound and improved genetic encoding 基于cramsamr - rao下界和改进遗传编码的地下空间微震传感器网络优化

IF 8.2 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2025-08-01 Epub Date: 2025-06-08 DOI: 10.1016/j.undsp.2025.02.009

Yichao Rui , Jie Chen , Junsheng Du , Xiang Peng , Zelin Zhou , Chun Zhu

The layout of a sensor network is a critical determinant of the precision and reliability of microseismic source localization. Addressing the impact of sensor network configuration on positioning accuracy, this paper introduces an innovative approach to sensor network optimization in underground space. It utilizes the Cramér-Rao Lower Bound principle to formulate an optimization function for the sensor network layout, followed by the deployment of an enhanced genetic encoding to solve this function and determine the optimal layout. The efficacy of proposed method is rigorously tested through simulation experiments and pencil-lead break experiments, substantiating its superiority. Its practical utility is further demonstrated through its application in a mining process within underground spaces, where the optimized sensor network solved by the proposed method achieves remarkable localization accuracy of 15 m with an accuracy rate of 4.22% in on-site blasting experiments. Moreover, the study elucidates general principles for sensor network layout that can inform the strategic placement of sensors in standard monitoring systems.

传感器网络的布局是决定微震源定位精度和可靠性的关键因素。针对传感器网络配置对定位精度的影响，提出了一种创新的地下空间传感器网络优化方法。利用cram - rao下界原理建立传感器网络布局的优化函数，利用增强的遗传编码对该函数进行求解，确定最优布局。通过仿真实验和铅笔芯断裂实验，验证了该方法的有效性，证明了其优越性。通过在地下空间采矿过程中的应用，进一步证明了该方法的实用性，在现场爆破实验中，采用该方法求解的优化传感器网络的定位精度达到了15 m，准确率为4.22%。此外，该研究阐明了传感器网络布局的一般原则，可以为标准监测系统中传感器的战略放置提供信息。

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引用次数: 0

Multi-patch attention Transformer for multivariate long-term time series forecasting of TBM excavation parameters TBM开挖参数多变量长期时间序列预测的多补丁关注变压器

IF 8.2 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2025-08-01 Epub Date: 2025-06-03 DOI: 10.1016/j.undsp.2025.02.007

Mingjun Liu , Jianqin Liu , Wei Guo , Hongxu Liu , Xiao Guo

To address the research gap in multivariable long-term time series forecasting in the field of tunnel boring machine (TBM) and provide long-term insights for decision-making in TBM construction, this paper studies a novel Transformer-based forecasting model. Leveraging a multi-patch attention mechanism, the newly developed multi-patch attention Transformer (MPAT) model is designed to predict long-term trends of multiple TBM operation parameters. The innovation lies in finding the most relevant time delay series of the input series through autocorrelation calculation, and designing a multi-patch attention mechanism to replace the traditional attention mechanism of Transformer, so that the model can capture local and global information of the series and improve the accuracy of long-term prediction of high-frequency and weakly periodic TBM data. Experimental results have shown that MPAT model has a significant effect on capturing TBM data in terms of temporal dependencies. In a case study, we applied MPAT to the Rongjiang Guanbu Water Diversion Project in Guangdong Province and predicted four excavation parameters. The experimental results show that MPAT exhibits accurate predictive ability when the input length is 36 and the outputs are 12, 24, 48, and 72, respectively. In comparison with some state-of-the-art models, MPAT outperforms MSE by 19.1%, 23.6%, 36.4%, and 48.3%, respectively. We also discussed the impact of input length and the number of patches on performance, and found that each prediction length has the best input length corresponding to it, and longer inputs don’t represent more accurate predictions. The determination of the number of patches should also depend on the input length, as too many or too few patches can affect the capture of local information in the sequence.

为了解决隧道掘进机多变量长期时间序列预测的研究空白，为隧道掘进机施工决策提供长期参考，本文研究了一种基于变压器的隧道掘进机预测模型。利用多补丁注意机制，新开发的多补丁注意转换器（MPAT）模型用于预测TBM多个运行参数的长期趋势。创新之处在于通过自相关计算找到输入序列中最相关的时滞序列，并设计了一种多补丁关注机制来取代Transformer的传统关注机制，使模型能够捕获该序列的局部和全局信息，提高高频弱周期TBM数据的长期预测精度。实验结果表明，MPAT模型在时间依赖性方面对TBM数据的捕获效果显著。以广东容江关埠引水工程为例，应用MPAT对4个开挖参数进行了预测。实验结果表明，当输入长度为36，输出长度为12、24、48和72时，MPAT具有准确的预测能力。与一些最先进的模型相比，MPAT分别比MSE高出19.1%、23.6%、36.4%和48.3%。我们还讨论了输入长度和patch数量对性能的影响，发现每个预测长度都有与之相对应的最佳输入长度，更长的输入并不代表更准确的预测。补丁数量的确定还应取决于输入长度，因为补丁太多或太少都会影响序列中局部信息的捕获。

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引用次数: 0

Minimizing problems and maximizing benefits from underground space use 从地下空间的使用中尽量减少问题和最大限度地提高效益

IF 8.2 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2025-08-01 Epub Date: 2025-05-08 DOI: 10.1016/j.undsp.2025.02.001

Raymond L. Sterling

For thousands of years, humans have used the underground for many purposes and we are now in an era when such uses are becoming more important to support our living patterns, our material needs and to improve the sustainability of our way of life. Many underground facilities serve their intended function well and have proven to have long lifetimes. Some have not been so successful for a variety of reasons or have been retired as no longer meeting the original purpose and not being suitable for conversion to another purpose. While the difference between success and failure is often tied to the specifics of a particular project, this paper seeks to extract some of the general principles that underlie the benefits or drawbacks of different types of underground space uses and how to maximize “success”. The paper is a mixture of the general and the specific because both play a role in success. The paper draws significantly from a recent study of the “lessons learned” from 42 worldwide underground facilities with an average of over 37 years of service mixed with other observations by the author from a career of studying underground space use and underground construction technologies.

几千年来，人类将地下用于许多目的，我们现在所处的时代，这种用途对支持我们的生活模式、物质需求和提高我们生活方式的可持续性变得越来越重要。许多地下设施都能很好地发挥其预期功能，并已被证明具有很长的使用寿命。有些由于各种原因而不那么成功，或已退休，不再符合原来的目的，不适合改为其他目的。虽然成功与失败之间的差异通常与特定项目的具体情况有关，但本文试图提取一些一般原则，这些原则构成了不同类型地下空间使用的利弊，以及如何最大限度地实现“成功”。这篇论文是一般和具体的混合，因为两者都在成功中发挥作用。本文主要借鉴了最近对全球42个地下设施的“经验教训”的研究，这些设施的平均服务时间超过37年，并结合了作者研究地下空间利用和地下建筑技术的其他观察结果。

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引用次数: 0

Practical use of initial displacement monitoring for predicting support behavior with asymmetric deformation in deep tunnel 初始位移监测在深部隧道非对称变形支护性能预测中的应用

IF 8.2 1区工程技术 Q1 ENGINEERING, CIVIL

Underground Space

Pub Date : 2025-08-01 Epub Date: 2025-04-17 DOI: 10.1016/j.undsp.2025.01.005

Takeshi Sato , Fumiharu Nakahara , Kazuo Sakai , Weiren Lin , Kiyoshi Kishida

Displacement monitoring provides essential information for safe and rational tunnel excavation. The data obtained allow engineers to analyze and predict tunnel behavior, facilitating the selection of appropriate supports and the evaluation of their effectiveness. In a recent tunnelling project in the Akaishi Mountains of central Japan, displacement monitoring was intensively implemented to ensure the stability of the 4.2-km-long Hirogawara adit, excavated to a maximum depth of 832 m. Analysis revealed a strong correlation between initial and final displacements. However, the tunnel experienced occasional support deformations. To address this, the trend of 3D absolute displacements was analyzed to predict and evaluate asymmetric deformation. The effective use of 1-cycle displacement monitoring proved critical for predicting final displacements and optimizing rock supports, particularly in cases with high overburden and limited geotechnical information.

位移监测为安全合理的隧道开挖提供了必要的信息。获得的数据允许工程师分析和预测隧道的行为，便于选择适当的支护和评估其有效性。最近在日本中部赤石山脉的一个隧道工程中，为了确保最大开挖深度为832米、长4.2公里的Hirogawara隧道的稳定性，进行了密集的位移监测。分析显示，初始位移和最终位移之间存在很强的相关性。然而，隧道偶尔会发生支护变形。为了解决这一问题，分析了三维绝对位移的趋势，以预测和评估非对称变形。事实证明，有效使用1周期位移监测对于预测最终位移和优化岩石支撑至关重要，特别是在覆盖层高且岩土信息有限的情况下。

引用次数: 0