Tunnelling and Underground Space Technology最新文献

{"title":"Replicating the sequential excavation method in tunnel model tests","authors":"Xuchao Du ,&nbsp;Yao Li ,&nbsp;Xing Dong ,&nbsp;Zhanglong Guo ,&nbsp;Houxian Chen","doi":"10.1016/j.tust.2025.106425","DOIUrl":"10.1016/j.tust.2025.106425","url":null,"abstract":"<div><div>To investigate soil deformation and stress distribution during tunnel excavation, a series of model tests were conducted at varying buried depths. These tests replicated the three-bench excavation method employed in the Luochuan Tunnel, utilizing prefabricated initial support segments connected by 3D-printed sliding connectors to achieve rapid sequential excavations and support installations. The results indicated that: (1) Increased buried depth enhances soil stability before excavation and reduces both the duration and magnitude of tunneling-induced disturbances. (2) A longitudinal soil arch forms in advance of the excavation face and weakens as the excavation face approaches the monitored cross-section. During excavation, the soil above the tunnel’s maximum width line exhibits a strong stress unloading effect, while the lower soil experiences significant loading. Consequently, the soil pressure in different directions takes on a bottle shape before excavation and transitions to a butterfly shape during and after excavation. (3) As buried depth increases, the triangular core soil arch transforms into an M-shape, accompanied by an increase in both the height of the core soil arch and the extent of the loosened zone. (4) For a given tunnel width, the distance of surface cracks from the centerline increases with buried depth, suggesting the presence of inclined failure planes rather than vertical failure planes above the tunnel, as proposed by Terzaghi.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"158 ","pages":"Article 106425"},"PeriodicalIF":6.7,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143199375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical and experimental investigation into dynamic fracture and energy dissipation of red sandstone under multi-axial confining pressure","authors":"Jianhua Yang ,&nbsp;Tao Yu ,&nbsp;Zhiwei Ye ,&nbsp;Yi Zou ,&nbsp;Chuangbing Zhou","doi":"10.1016/j.tust.2025.106446","DOIUrl":"10.1016/j.tust.2025.106446","url":null,"abstract":"<div><div>Investigating the dynamic behavior of rock under confining pressure is instrumental in enhancing the understanding of rock fracture characteristics and energy efficiency of deep rock blasting. Related investigations have been conducted extensively by using modified Split Hopkinson Pressure Bar (SHPB) apparatus. However, in these experimental tests, the real-time observation of the dynamic fracture process of rock remains a significant challenge due to confinement. Numerical simulation offers a viable solution to overcome this obstacle. In this study, a full-scale numerical model of a true triaxial SHPB test system is first developed by using the hybrid discrete element method and finite difference method (DEM-FDM). Then the numerical triaxial SHPB is experimentally validated through assessments of stress wave propagation, dynamic stress equilibrium and dynamic stress–strain behavior in rock. By employing the numerical triaxial SHPB tests in combination with the experimental tests, the dynamic fracture behavior and energy dissipation of red sandstone under biaxial and triaxial confining pressure are investigated. Based on these investigations, the energy required for rock fragmentation by blasting under in-situ stress is discussed. The numerical and experimental results show that the strain rate effect on the dynamic compressive strength of red sandstone is related to the state of confining pressure, exhibiting a decrease with increasing axial pressure and an increase with increasing lateral pressure. Both tensile and shear microcracks are generated within the rock specimen under the coupled uniaxial impact loading and multi-axial confining pressure. As the axial pressure increases, there is an augmentation in the total number of microcracks, accompanied by an escalated proportion of tensile cracks. Consequently, the dynamic fracture behavior of rock is predominated by tensile failure. Conversely, the total number of microcracks decreases and shear failure becomes the primary fracture pattern with an increase in the lateral pressure. The dynamic specific fracture energy required for creating a new fracture surface of unit area correspondingly decreases with increasing axial pressure while increases with increasing lateral pressure. Compared to biaxial or triaxial anisotropic pressure states with the same average pressure, the energy required for rock fracture is highest under the triaxial isotropic pressure condition. Regarding deep rock blasting under in-situ stress, the fracture zone decreases and the energy consumption in rock fragmentation increases with the increase of the stress level, indicating that rock blasting under high in-situ stress becomes more challenging.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"158 ","pages":"Article 106446"},"PeriodicalIF":6.7,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143097332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel approach to seismic fragility evaluation of underground structures considering hybrid epistemic uncertainties of both seismic demand and capacity","authors":"Minze Xu ,&nbsp;Chunyi Cui ,&nbsp;Jingtong Zhao ,&nbsp;Chengshun Xu ,&nbsp;Kun Meng","doi":"10.1016/j.tust.2024.106278","DOIUrl":"10.1016/j.tust.2024.106278","url":null,"abstract":"<div><div>Precise seismic fragility analysis holds significant importance in the evaluation of seismic resilience for underground structures. However, the conventional seismic fragility analysis of underground structures usually ignores the hybrid epistemic uncertainties caused by the limited samples of both seismic demand and thresholds and deterministic boundaries between different limit states, which can inevitably cause errors in the seismic resilience evaluation of underground structures. Thus, focusing on the quantification of epistemic uncertainties, this paper aims to propose an approach to seismic fragility evaluation of underground structures considering hybrid epistemic uncertainties of both seismic demand and capacity. In this approach, the analytical formulation of seismic fragility considering the fuzziness of limit states is firstly derived via adopting the entropy equivalence method. Then, the non-parametric Bootstrap method and maximum entropy principle, as well as the Copula theory are combined to establish a probability model characterizing the statistical uncertainties of both seismic demand and capacity. On this basis, the variability of failure probability of underground structures is quantified, and the envelope fuzzy seismic fragility is obtained. Moreover, the influences of the coupling effect of statistical uncertainty and fuzziness on the seismic fragility of underground structures are also analyzed in this paper. The results show that the seismic fragility of underground structures based on limited samples of both seismic demand and thresholds and deterministic boundaries between different limit states has significant variability, and the variability degree of fragility is various under different ground motion intensities. Besides, the envelope fuzzy seismic fragility curves can effectively reflect the coupling effect of statistical uncertainty and fuzziness and adequately characterize the variability of estimated seismic fragility, which can provide a more accurate basis for seismic resilience evaluation of underground structures.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"156 ","pages":"Article 106278"},"PeriodicalIF":6.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142788872","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-objective optimization framework for generative design of horseshoe-shaped pipe arrangement in pre-stressed underground bundles","authors":"Wen He ,&nbsp;Yue Pan ,&nbsp;Yongmao Hou ,&nbsp;Jin-Jian Chen","doi":"10.1016/j.tust.2025.106437","DOIUrl":"10.1016/j.tust.2025.106437","url":null,"abstract":"<div><div>The underground bundle composite pipe integrated by transverse pre-stressing (UBIT) is an emerging method for underground excavation. It offers advantages such as the enhanced structural performance, reduced deformation, simplified construction process, and improved economic efficiency. However, the complexity inherent in the UBIT structure, coupled with the subjective nature of individual experience, renders the manual design of the UBIT pipe arrangement within tunnel cross-sections a challenging task. To address this, this research proposes an intelligent design method named multi-objective optimization-based generative design (MOOGD), which combines multi-objective optimization principles with generative design techniques. The proposed MOOGD has two main innovations: (a) It enables an “end-to-end” design process that enhances efficiency while minimizing human errors; (b) It incorporates five classic multi-objective optimization algorithms, offering flexibility for engineers to select or substitute algorithms based on specific project needs. The effectiveness of MOOGD is validated through a case study of the Pingli Station construction project on Shanghai Metro Line 20. It is a two-layer underground station in Shanghai Metro Line 20, with a horseshoe-shaped circular tunnel cross-section. Compared to the original engineering design, the MOOGD-based UBIT pipe arrangement design solutions using five candidate multi-objective optimization algorithms achieve significant improvements of 11.03 %, 10.64 %, 10.95 %, 10.89 %, and 10.80 %, respectively. MOOGD provides a highly efficient and reliable design tool for engineers, facilitating a rapid exploration of design alternatives and the automated generation of optimal UBIT pipe arrangements that adhere to real-world engineering specifications.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"158 ","pages":"Article 106437"},"PeriodicalIF":6.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143097331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of the impact of landscape zone on driver distraction and visual comfort in road tunnels","authors":"Jia Liu ,&nbsp;Fei Ye ,&nbsp;Wenhao Zhu ,&nbsp;Enjie Su ,&nbsp;Wenbo Peng ,&nbsp;Xingbo Han ,&nbsp;Xiaobao Wen","doi":"10.1016/j.tust.2024.106248","DOIUrl":"10.1016/j.tust.2024.106248","url":null,"abstract":"<div><div>Studies have shown that accidents in tunnels can be more severe than those in open road networks, and drivers are considered the critical factor for such accidents. An in-depth understanding of driver behavior helps analyze pre-accident safety measures and develop policies. Decoration of landscape zones is considered an effective measure for improving the driving environment inside road tunnels and has been widely adopted in China. However, the research on the impact of landscape zones on driving safety and comfort remains inadequate. It is worthwhile to explore whether the rich and colorful decoration of landscape zones results in driver distraction by excessively capturing driver’s attention, thereby increasing accident risk. To investigate this issue, a driving simulator was used, and tunnel interior scenarios characterized by three landscape zones with different spatial distributions (namely “wall,” “vault,” and “round”) were established. Eye tracking, driving performance, and pupil diameter data were collected to further analyze the driver’s psychological and physiological conditions while driving. The results showed that i) compared to no-landscape zones, the number of driver distractions increased when driving through landscape zones, with distractions caused by vault and round landscapes being particularly noticeable; ii) wall landscapes have certain advantage in maintain longitudinal driving speeds of vehicles more stable; iii) using normalized pupil diameter as an indicator for evaluating visual sensation, all three landscape zones can effectively improve the driver’s visual comfort, with no significant differences among the three; and iv) the pupil diameter changes of the wall landscapes were relatively stable compared to others, indicating the preference for landscape decoration on sidewalls inside the tunnels. The results of this investigation provide new insights into measures for improving the driving environment inside the road tunnels.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"156 ","pages":"Article 106248"},"PeriodicalIF":6.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142788875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Groundwater environmental effects risk evaluation in mountain tunnel construction: A dynamic decision support system based on fuzzy two-dimensional cloud probability model","authors":"Huaiyuan Sun ,&nbsp;Ling Le ,&nbsp;Yiming Dai ,&nbsp;Yi Rui ,&nbsp;Hehua Zhu ,&nbsp;Xiaojun Li ,&nbsp;Xuhui Li ,&nbsp;Guangwen Xue","doi":"10.1016/j.tust.2024.106276","DOIUrl":"10.1016/j.tust.2024.106276","url":null,"abstract":"<div><div>The underground water environment in mountain tunnels constitutes a complex system. During tunnel construction, the interaction between tunnel and underground water environment can lead to chain construction accidents and environmental damage. Identifying comprehensive risks of underground water environment effects and making rational decisions are crucial. Considering the diversity, complexity, uncertainty, and dynamics of groundwater environmental effects, this study develops a risk decision support system for tunnel construction. Firstly, to reflect the complexity and diversity of groundwater environmental effects, a disaster chain is established, and two indicator systems are extracted. Secondly, dynamic datasets are generated using a combination of expert system knowledge base and multi-source data fusion. Finally, based on the theories of fuzzy mathematic and two-dimensional cloud model, along with probabilistic algorithm, this study proposes a Fuzzy Two-Dimensional Cloud Probability Model (FTDCPM) to quantify the uncertainty of groundwater environmental effects. This engineering system can provide reference in similar projects.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"156 ","pages":"Article 106276"},"PeriodicalIF":6.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142788881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Failure characteristics of tunnels neighbouring karst fissures: Insights from laboratory observations and machine learning-interpreted simulations","authors":"Enlin Ma ,&nbsp;Jinxing Lai ,&nbsp;Xulin Su ,&nbsp;Tao Peng ,&nbsp;Junling Qiu","doi":"10.1016/j.tust.2024.106252","DOIUrl":"10.1016/j.tust.2024.106252","url":null,"abstract":"<div><div>This study primarily investigates the mechanical responses and failure mechanisms of tunnels adjacent to karst fissures through detailed laboratory model experiments, supplemented by machine learning-interpreted simulations. Utilizing a novel tunnel-karst fissure model test system, we meticulously analysed stress and displacement evolution within the surrounding rock during tunnel excavation, elucidating unevenness and complexity of the rock displacement-stress field induced by the fissure’s low stiffness. The experimental findings delineate the critical phases of rock instability, showcasing how hydraulic pressures interact with karst features to induce failure. Key experimental results indicate a mechanism for the formation of water inrush channels, which are crucial for understanding tunnel vulnerability near karst fissures. Complementing the physical experiments, a deep residual network (ResNet), interpreted using SHapley Additive exPlanations (SHAP), was employed to quantify the impacts of fissure positions, lateral pressure coefficients, and hydraulic pressures on the critical safety distances of fissures, according to simulation results. This integrated approach enhances the precision of risk assessments and supports the development of targeted mitigation strategies in karst-affected tunnelling projects, thereby improving the safety and sustainability of underground constructions.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"156 ","pages":"Article 106252"},"PeriodicalIF":6.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142788873","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental study on joint behaviour of immersed tunnel subjected to differential settlement","authors":"Jianfeng Li ,&nbsp;Pengpeng Ni ,&nbsp;Zhiwang Lu","doi":"10.1016/j.tust.2024.106261","DOIUrl":"10.1016/j.tust.2024.106261","url":null,"abstract":"<div><div>Differential settlement can cause concentrated deformation in the joints of immersed tunnel during its service stage. In this study, a model for simulating immersion joint was proposed, and tests on immersed tunnels under varying differential settlement were conducted. The mechanical behaviours of joints, including vertical displacement, shear displacement, rotation angle, and joint opening, were systematically analysed. Upon the successful simulation of joint against other works, further experiments were performed to underscore the influence of axial constraint and location of differential settlement. Results indicate that axial constraints can enhance the load transfer capacity and improve the uniformity of joint shear forces and rotation angles, accommodating a larger allowable range of differential settlement for immersed tunnel. The parameter of accommodating deformation ratio was defined to characterise the ratio between maximum axial deformation of joint to compression amount of Gina gasket, which could evaluate the effects of axial constraints on joint opening. Setting the accommodating deformation ratio to 1 can increased the allowable differential settlement by 36%. The location of differential settlement affected the load distribution greatly, with respect to shear and bending behaviour of joints. Settlement at the mid-span of a tunnel element rather than a joint was generally safer for immersed tunnel.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"156 ","pages":"Article 106261"},"PeriodicalIF":6.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142788874","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Slow walking behavior with negative emotion in smoke-filled model-scale tunnel","authors":"Wenhao Li,&nbsp;Miho Seike,&nbsp;Akimasa Fujiwara,&nbsp;Makoto Chikaraishi","doi":"10.1016/j.tust.2024.106224","DOIUrl":"10.1016/j.tust.2024.106224","url":null,"abstract":"<div><div>This study delved into the fundamental relationship between negative emotions and slow walking behaviors in a smoke-filled model-scale tunnel. Behavioral patterns and emotional responses were investigated by video observations and physiological signals. Contrary to previous assumptions, it was revealed that the “slow” was not solely indicative of older people, children, or individuals with disabilities. 15.3% of the slow participants paused several times during evacuation, with those in stress and low-stress cases pausing to look around, whereas a portion of those in fear and anxiety cases did nothing during their pause, potentially linked to threat-induced states such as orienting, freezing, and tonic immobility. 20.7% evacuated while stooping, possibly because of participants’ background (the disaster prevention education in Japan). The Difference-in-Differences (DID) estimation results indicated that negative emotions exerted a more pronounced influence on slow speeds compared to the overall speeds.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"156 ","pages":"Article 106224"},"PeriodicalIF":6.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142788880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simulation of subway flood evacuation based on modified social force model","authors":"Yulong Li ,&nbsp;Dongyue Xu ,&nbsp;Jinghong Wang ,&nbsp;Juan Liu ,&nbsp;Yan Wang ,&nbsp;Juncheng Jiang","doi":"10.1016/j.tust.2024.106244","DOIUrl":"10.1016/j.tust.2024.106244","url":null,"abstract":"<div><div>The issue of crowd evacuation during sudden floods in subway stations has gained increasing attention in recent years. However, previous studies have not sufficiently examined the influence of flood flow characteristics, such as location and velocity, on pedestrian evacuation. This gap has limited the effectiveness of current flood evacuation models for subway stations, restricting their utility in formulating robust emergency evacuation strategies. In response, this paper introduces a modified social force model that integrates the combined effects of flood flow depth and velocity at various station locations on pedestrian movement, while also accounting for the role of obstacles during flood evacuation. A case study of an actual subway station under flood conditions demonstrates that flow presence notably reduces evacuation efficiency, with varying effects depending on location. Evacuation efficiency generally declines initially before improving as flood conditions persist, reaching its lowest point at a platform flood velocity of 0.5 m/s and highest at 2 m/s. On staircases and escalators, increased flood flow velocity correlates with reduced evacuation success rate. In terms of emergency response, strategically placing obstacles in flooded areas enhances evacuation efficiency, reducing evacuation time by up to 16.1 % and improving the success rate by as much as 17.8 %. The key contribution of this study is the introduction of a new methodology for flood evacuation research in subway stations, offering a scientific basis for designing effective emergency evacuation plans and safety measures.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"156 ","pages":"Article 106244"},"PeriodicalIF":6.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142788876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}