Underground Space最新文献

{"title":"Physical and mechanical response of large-diameter shield tunnel lining structure under non-uniform fire: A full-scale fire test-based study","authors":"","doi":"10.1016/j.undsp.2024.06.001","DOIUrl":"10.1016/j.undsp.2024.06.001","url":null,"abstract":"<div><p>When a fire occurs in an underground shield tunnel, it can result in substantial property damage and cause permanent harm to the tunnel lining structure. This is especially true for large-diameter shield tunnels that have numerous segments and joints, and are exposed to specific fire conditions in certain areas. This paper constructs a full-scale shield tunnel fire test platform and conducts a non-uniform fire test using the lining system of a three-ring large-diameter shield tunnel with an inner diameter of 10.5 m. Based on the tests, the temperature field distribution, high-temperature bursting, cracking phenomena, and deformation under fire conditions are observed. Furthermore, the post-fire damage forms of tunnel lining structures are obtained through the post-fire ultimate loading test, and the corresponding mechanism is explained. The test results illustrate that the radial and circumferential distribution of internal temperature within the tunnel lining, as well as the radial temperature gradient distribution on the inner surface of the lining, have non-uniform distribution characteristics. As a result, the macroscopic phenomena of lining concrete bursting and crack development during the fire test mainly occur near the fire source, where the temperature rise gradient is the highest. In addition, the lining structure has a deformation characteristic of local outward expansion and cannot recover after the fire load is removed. The ultimate form of damage after the fire is dominated by crush damage from the inside out of the lining joints in the fire-exposed area. The above results serve as a foundation for future tunnel fire safety design and evaluation.</p></div>","PeriodicalId":48505,"journal":{"name":"Underground Space","volume":null,"pages":null},"PeriodicalIF":8.2,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2467967424000825/pdfft?md5=8e388e786b80d4a679e702694beefa95&pid=1-s2.0-S2467967424000825-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142163956","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":"Seismic performance study of immersed tunnel with longitudinal limit device of flexible joint","authors":"","doi":"10.1016/j.undsp.2024.04.007","DOIUrl":"10.1016/j.undsp.2024.04.007","url":null,"abstract":"<div><p>Flexible joints represent the most vulnerable aspect of the immersed tunnel, necessitating effective waterproofing and the transmission of forces between tunnel segments. However, the role of longitudinal limit devices in the seismic behavior of immersed tunnels is frequently overlooked in contemporary research on their seismic robustness. This study develops a longitudinal force model for flexible joints that incorporates the longitudinal limit device, building upon the beam-spring model of the immersed tunnel. Concurrently, a scaled partial experiment on the immersed tunnel’s flexible joint is undertaken, and validated and compared to the theoretical model. Subsequently, this model is utilized in the seismic assessment of the Ruyifang immersed tunnel. The computational findings revealed a considerable improvement in the seismic resilience of the immersed tunnel following the integration of longitudinal limit devices. With the incorporation of these devices, the opening of flexible joints diminished by 20% to 50% compared to scenarios lacking such devices. In addition, the peak acceleration of the tunnel segments’ mid-point structural response decreased by approximately 50%, accompanied by a significant reduction in the internal force response within the tunnel segments. As proposed in this research, the longitudinal force model for flexible joints under longitudinal limit devices represents the behavior of immersed tunnels under seismic stress more accurately. These numerical simulation outcomes also offer valuable insights for designing flexible joints in immersed tunnels.</p></div>","PeriodicalId":48505,"journal":{"name":"Underground Space","volume":null,"pages":null},"PeriodicalIF":8.2,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2467967424000795/pdfft?md5=242d717c47bdf3fc56715b83905cadb4&pid=1-s2.0-S2467967424000795-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142229035","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":"Integrated approach of predicting rock stability in high mountain valley underground caverns","authors":"","doi":"10.1016/j.undsp.2024.04.005","DOIUrl":"10.1016/j.undsp.2024.04.005","url":null,"abstract":"<div><p>High mountain valleys are characterized by the development of intricate ground stress fields due to geological processes such as tectonic stress, river erosion, and rock weathering. These processes introduce considerable stability concerns in the surrounding rock formations for underground engineering projects in these regions, highlighting the imperative need for rigorous stability assessments during the design phase to ensure construction safety. This paper introduces an innovative approach for the pre-evaluation of the stability of surrounding rocks in underground caverns situated within high mountain valleys. The methodology comprises several pivotal steps. Initially, we conduct inverse calculations of the ground stress field in complex geological terrains, combining field monitoring and numerical simulations. Subsequently, we ascertain stress-strength ratios of the surrounding rocks using various rock strength criteria. To assess the stability characteristics of the surrounding rocks in the 1^# spillway cave within our project area, we employ numerical simulations to compute stress-strength ratios based on different rock strength criteria. Furthermore, we undertake a comparative analysis, utilizing data from the 5^# Underground Laboratory (Lab 5) of Jinping II Hydropower Station, aligning the chosen rock strength criterion with the damage characteristics of Lab 5′s surrounding rocks. This analysis serves as the cornerstone for evaluating other mechanical responses of the surrounding rocks, thereby validating the pre-evaluation methodology. Our pre-evaluation method takes into account the intricate geological evolution processes specific to high mountain valleys. It also considers the influence of the initial geostress field within the geological range of underground caverns. This comprehensive approach provides a robust foundation for the analysis and assessment of the stability of surrounding rocks, especially in high mountain valley areas, during the design phase of underground engineering projects. The insights derived from this analysis hold substantial practical significance for the effective guidance of such projects.</p></div>","PeriodicalId":48505,"journal":{"name":"Underground Space","volume":null,"pages":null},"PeriodicalIF":8.2,"publicationDate":"2024-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2467967424000746/pdfft?md5=0f212efa334d36d48b5f77f1824979d9&pid=1-s2.0-S2467967424000746-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141838869","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":"Model test on cutterhead-soil interaction during shield tunneling and its theoretical model","authors":"","doi":"10.1016/j.undsp.2024.03.006","DOIUrl":"10.1016/j.undsp.2024.03.006","url":null,"abstract":"<div><p>This study aims to develop a rational theoretical model for cutterhead-soil interaction. The cutterhead-soil interaction mechanism is divided into two components: the cutting action of the cutter on the soil and the extrusion of the cutterhead on the soil. By enhancing the Mckyes–Ali model, we analyze and deduce the force state of the cutter during shield tunneling, obtaining a calculation method for determining the force on the cutter. Additionally, we conduct an in-depth analysis of the extrusion effect of the cutterhead on the soil during shield tunneling, utilizing the fundamental solution of the Kelvin problem. Based on these theoretical calculations, we validate the tunneling thrust and cutterhead torque of the shield using our self-developed multi-functional large-scale shield tunneling test platform. The test results demonstrate that the tunneling thrust and cutterhead torque derived from the established cutterhead-soil interaction model in this paper are relatively close to the experimental monitoring values. This provides a theoretical foundation for establishing reasonable shield tunneling loads.</p></div>","PeriodicalId":48505,"journal":{"name":"Underground Space","volume":null,"pages":null},"PeriodicalIF":8.2,"publicationDate":"2024-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2467967424000722/pdfft?md5=6100098abc815e1895e44ae09c9c2df5&pid=1-s2.0-S2467967424000722-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141847383","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":"Vibration transfer from underground train to multi-story building: Modelling and validation with in-situ test data","authors":"","doi":"10.1016/j.undsp.2024.04.004","DOIUrl":"10.1016/j.undsp.2024.04.004","url":null,"abstract":"<div><p>Excessive underground train-induced vibration becomes a serious environmental problem in cities. To investigate the vibration transfer from an underground train to a building nearby, an explicit-integration time-domain, three-dimensional finite element model is developed. The underground train, track, tunnel, soil layers and a typical multi-story building nearby are all fully coupled in this model. The complex geometries involving the track components and the building are all modelled in detail, which makes the simulation of vibration transfer more realistic from the underground train to the building. The model is validated with in-situ tests data and good agreements have been achieved between the numerical results and the experimental results both in time domain and frequency domain. The proposed model is applied to investigate the vibration transfer along the floors in the building and the influences of the soil stiffness on the vibration characteristics of the track-tunnel-soil-building system. It is found that the building vibration induced by an underground train is dominant at the frequency determined by the P2 resonance and influenced by the vibration modes of the building. The vertical vibration in the building decreases in a fluctuant pattern from the foundation to the top floor due to loss of high frequency contents and local modes. The vibration levels in different rooms at a same floor can be different due to the different local stiffness. A room with larger space thus smaller local stiffness usually has higher vibration level. Softer soil layers make the tunnel lining and the building have more low frequency vibration. The influence of the soil stiffness on the amplification scale along the floors of the building is found to be nonlinear and frequency-dependent, which needs to be further investigated.</p></div>","PeriodicalId":48505,"journal":{"name":"Underground Space","volume":null,"pages":null},"PeriodicalIF":8.2,"publicationDate":"2024-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2467967424000710/pdfft?md5=d73516275ef4edd5f9166ea38a8c8160&pid=1-s2.0-S2467967424000710-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141696351","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":"Optimization of spatial layouts for underground facilities to achieve carbon neutrality in cities: A multi-agent system model","authors":"Lingxiang Wei ,&nbsp;Dongjun Guo ,&nbsp;Junyuan Ji ,&nbsp;Zhilong Chen ,&nbsp;Huapeng Hu ,&nbsp;Xiaoli Peng","doi":"10.1016/j.undsp.2024.03.005","DOIUrl":"https://doi.org/10.1016/j.undsp.2024.03.005","url":null,"abstract":"<div><p>Subways, underground logistics systems and underground parking, as the primary facilities types of underground, contribute significantly to the achievement of carbon–neutral cities by moving surface transportation to underground, thereby releasing surface space for the creation of more urban blue-green space for carbon sink. Therefore, in-depth studies on carbon neutrality strategies as well as reliable layout optimization solutions of these three types of underground facilities are required. This study proposes a spatial layout optimization strategy for carbon neutrality using underground hydrogen storage and geothermal energy for these three types of underground facilities employing a multi-agent system model. First, three spatial layout relationships, competition, coordination, and followership, between five underground facilities that contribute to emission reduction were investigated. Second, the implementation steps for optimizing the spatial layout of underground facilities were determined by defining the behavioral guidelines for spatial environment, underground facility, and synergistic agent. Finally, using the Tianfu New District in Chengdu City, China, as a case study, layouts of underground facilities under three different underground space development scenarios were simulated to verify the model. The findings of this study address the gap in the research on underground spatial facilities and their layout optimization in response to emission reduction. This study provided a significant reference for the study of underground space and underground resources at the planning level to aid in achieving carbon–neutral cities.</p></div>","PeriodicalId":48505,"journal":{"name":"Underground Space","volume":null,"pages":null},"PeriodicalIF":8.2,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S246796742400062X/pdfft?md5=6869e2d580c2e3bfac61c8356bb60278&pid=1-s2.0-S246796742400062X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141605096","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":"Permeability evolution of fluid-injection-reactivated granite fractures of contrasting roughnesses","authors":"","doi":"10.1016/j.undsp.2024.02.007","DOIUrl":"10.1016/j.undsp.2024.02.007","url":null,"abstract":"<div><p>Fracture/fault instability induced by fluid injection in deep geothermal reservoirs could not only vary the reservoir permeability but also trigger hazardous seismicity. To address this, we conducted triaxial shear experiments on granite fractures with different architected roughnesses reactivated under fluid injection, to investigate the controls on permeability evolution linked to reactivation. Our results indicate that the fracture roughness and injection strategies are two main factors affecting permeability evolution. For fractures with different roughnesses, a rougher fracture leads to a lower peak reactivated permeability (<em>k</em>_max), and varying the fluid injection strategy (including the confining pressure and injection rate) has a less impact on <em>k</em>_max, indicating that the evolution of permeability during fluid pressurization is likely to be determined by the fracture roughness along the shear direction. Both the fracture roughness and injection strategies affect the average rates of permeability change and this parameter also reflects the long-term reservoir recovery. Our results have important implications for understanding the permeability evolution and the injection-induced fracture/fault slips in granite reservoirs during the deep geothermal energy extraction.</p></div>","PeriodicalId":48505,"journal":{"name":"Underground Space","volume":null,"pages":null},"PeriodicalIF":8.2,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2467967424000631/pdfft?md5=b8c7f8910f33c92161733ec946e116f2&pid=1-s2.0-S2467967424000631-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141716351","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":"Optimal intensity measure for seismic performance assessment of shield tunnels in liquefiable and non-liquefiable soils","authors":"Yiyao Shen, M. Hesham El Naggar, Dongmei Zhang, Zhongkai Huang, Xiuli Du","doi":"10.1016/j.undsp.2024.03.008","DOIUrl":"https://doi.org/10.1016/j.undsp.2024.03.008","url":null,"abstract":"","PeriodicalId":48505,"journal":{"name":"Underground Space","volume":null,"pages":null},"PeriodicalIF":8.2,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141848500","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 shield tunnel seepage control via microbially induced calcite precipitation","authors":"Shuai Zhao, Shifan Wu, Dong-ming Zhang, Hongyu Huang, Jian Chu","doi":"10.1016/j.undsp.2024.03.007","DOIUrl":"https://doi.org/10.1016/j.undsp.2024.03.007","url":null,"abstract":"","PeriodicalId":48505,"journal":{"name":"Underground Space","volume":null,"pages":null},"PeriodicalIF":8.2,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141845501","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":"MatDEM-based study of disc cutter force model in open TBM tunnels: Incorporating installation radius and synergistic effects","authors":"Yadong Xue, Lushan Shu, Lan Zhao, Wei Luo, Yongfa Guo","doi":"10.1016/j.undsp.2024.02.008","DOIUrl":"https://doi.org/10.1016/j.undsp.2024.02.008","url":null,"abstract":"","PeriodicalId":48505,"journal":{"name":"Underground Space","volume":null,"pages":null},"PeriodicalIF":8.2,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141852516","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}