Tunnelling and Underground Space Technology最新文献

{"title":"Computed method for the thermal buckling performance of a constrained non-circular heated pipeline with an oval inverted arch","authors":"Qian Zhang ,&nbsp;Shiyi Zhang ,&nbsp;Meiling Shen ,&nbsp;Zhaochao Li","doi":"10.1016/j.tust.2025.106803","DOIUrl":"10.1016/j.tust.2025.106803","url":null,"abstract":"<div><div>This study focuses on the thermal buckling analysis of a confined noncircular pipeline with an oval inverted arch subjected to thermal loads. A trigonometric formula is employed to illustrate the radial inward deflection of the pipeline resulting from the rigid confinement of the surrounding medium (soils/rocks). The governing equations are derived by integrating the classical shell theory with energy criteria. These equations are solved to obtain the temperature–displacement equilibrium paths and critical temperature variations. Furthermore, a comprehensive comparison is conducted to validate the accuracy of the proposed computational method. This favourable alignment with other available solutions substantiates the effectiveness of this investigation. Finally, the impacts of varying central angles, ovalities, and thickness-to-radius ratios on the thermal stability of a noncircular pipeline with an oval inverted arch are analysed. These conclusions indicate that an increased central angle and ovality significantly affect the thermal stability of the system.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"164 ","pages":"Article 106803"},"PeriodicalIF":6.7,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144253522","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":"Research on the grease rear penetration escape behavior and the sealing performance of shield tail under static pressure of shield tail brush","authors":"Zhanlin Cao ,&nbsp;Shunhua Zhou ,&nbsp;Jianguo Liu ,&nbsp;Huiji Guo ,&nbsp;Honggui Di","doi":"10.1016/j.tust.2025.106785","DOIUrl":"10.1016/j.tust.2025.106785","url":null,"abstract":"<div><div>The shield tail sealing system plays a vital role in averting water-inflow incidents during shield tunneling, garnering considerable attention from both academic and engineering communities due to its sealing efficacy and failure determinants. This research investigates the influence of various shield tail clearances on the interaction between grease and shield tail brushes, as well as the subsequent escape of grease from the rear penetration, employing model experiments and mechanical scrutiny. The findings indicate that shield tail clearances significantly impact the elastic behavior of shield tail brushes. The reduction of the shield tail clearance has resulted in a notable enhancement in the working performance of the brushes. The escape process of grease from the rear penetration is delineated into four stages: grease filling, extrusion, rear penetration escape, and unloading. A critical threshold for grease pressure during rear penetration escape process is identified, which is contingent upon the differential pressure within and outside the shield tail brush, the elastic properties of the brush, and the shield tail clearance. As the shield tail clearance diminishes, both the contact force and the grease rear penetration escape pressure of the shield tail brush escalate markedly. Subsequently, employing a mechanical analysis method encompassing multiple parameters such as the elasticity of the shield tail brush, grease pressure, reduction coefficient, front protective plate, and rear clamping plate, alongside experimental findings, the error coefficient <em>K</em>₁ and shield tail brush elasticity proportionality coefficient <em>K</em>₂ are determined. This analysis delineates three regions for evaluating the grease rear penetration escape process: the grease brush effect region (Zone I), safety region (Zone II), and grease rear penetration escape region (Zone III).</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"164 ","pages":"Article 106785"},"PeriodicalIF":6.7,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144253518","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":"Full-scale experimental and numerical study of the influence of beams depth on the smoke flow characteristics in a long-closed channel with lateral opening","authors":"Ke Wang ,&nbsp;Weixin Tong ,&nbsp;Junrui Duan ,&nbsp;Jie Ji ,&nbsp;Fanliang Ge ,&nbsp;Zhiyong Wang","doi":"10.1016/j.tust.2025.106794","DOIUrl":"10.1016/j.tust.2025.106794","url":null,"abstract":"<div><div>This paper aims to study the influence of beams depth on the smoke flow characteristics in a long-closed channel with lateral opening and multiple ceiling beams. A series of full-scale experiments and numerical simulations with different fire heat release rates and beam depths were carried out. The influence of beams depth on the smoke spreading, the longitudinal ceiling temperature distribution, the maximum ceiling excess temperature, and the smoke mass flow along the channel were analyzed. Results show that the existence of the ceiling beams in the long channel with closed ends makes the smoke accumulate, which causes the time of the ceiling jet stage increase with the increase of beams depth. The longitudinal ceiling temperature decays faster and the maximum ceiling temperature rise becomes higher with the increasing depth of beams. Additionally, the prediction correlations of longitudinal ceiling temperature distribution and the maximum ceiling temperature rise in the long channel with ceiling beams were established. Based on the dimensional analysis, a quantitative correlation to predict the smoke mass flow under the beam is proposed considering both beam parameters (depth, width, and the distance from the fire source) and HRR. The smoke mass flow decreases with increased depth of beams due to the weakening of air entrainment, this phenomenon is distinct from the gradual increase of smoke mass flow observed in long channels with open sides. This study is anticipated to contribute to fire prevention and the understanding of the smoke flow pattern in the long-closed channel with lateral opening and ceiling beams.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"164 ","pages":"Article 106794"},"PeriodicalIF":6.7,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144253523","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":"Influence of prestress on failure response and reinforcement mechanism of anchorage layer in tunnels: Experimental insights from P-wave velocity and PIV analysis","authors":"Henghong Yang ,&nbsp;Mingnian Wang ,&nbsp;Li Yu ,&nbsp;Jie Liu ,&nbsp;Xiao Zhang ,&nbsp;Jun Liu ,&nbsp;Zhihui Xu","doi":"10.1016/j.tust.2025.106793","DOIUrl":"10.1016/j.tust.2025.106793","url":null,"abstract":"<div><div>The reinforcement of tunnels in weak surrounding rock using anchor bolts establishes an anchorage layer that collaborates in bearing loads, constituting a widely employed reinforcement technique. However, the bearing capacity of the anchorage layer remains unquantified, its failure response inadequately investigated, and the reinforcement mechanism of anchor bolts has yet to be comprehensively elucidated through a synthesis of mesoscopic and macroscopic perspectives. This study undertakes a series of anchorage layer loading and failure experiments under varying prestress values, aiming to quantify the bearing capacity by isolating the anchorage layer and investigating its failure response. To elucidate the reinforcement mechanism of the anchorage layer, the experiments integrate stress testing, P-wave velocity analysis, and PIV measurement. These methods provide a comprehensive perspective, elucidating stress distribution, integrity, and mechanical parameters at the mesoscopic perspective, alongside deformation and bearing capacity at the macroscopic perspective. The experimental results indicate that the failure of the surrounding rock layer (SRL) begins at the tunnel shoulder, while the failure of the anchorage layer (AL) and prestressed anchorage layer (PAL) begins at the tunnel crown, and the failure modes of AL and PAL are consistent. In comparison with SRL, both AL and PAL demonstrate notable enhancements in stress distribution, integrity, mechanical parameters, ductility, and bearing capacity. Notably, increasing the value of prestress further amplifies these improvements. For instance, relative to SRL, PAL (6P) exhibits a remarkable 244% increase in radial stress, a 23.26% rise in integrity, improvements of 23.21% in elastic modulus and 15.46% in cohesion, an approximate 217.75% enhancement in failure displacement, and striking increments of around 400% and 325% in failure load and ultimate load, respectively. From the mesoscopic perspective, the installation of anchor bolts modulates the stress distribution within the surrounding rock, enhances its integrity, and strengthens its mechanical parameters. This is subsequently manifested from the macroscopic perspective, where the ductility and bearing capacity of the surrounding rock are significantly enhanced.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"164 ","pages":"Article 106793"},"PeriodicalIF":6.7,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144261966","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":"Prediction of surface settlement caused by tunneling with ARMA based time-series decomposition","authors":"Changyu Wang ,&nbsp;Zude Ding ,&nbsp;Yuhang Shen ,&nbsp;Wenyun Ding ,&nbsp;Yongfa Guo","doi":"10.1016/j.tust.2025.106770","DOIUrl":"10.1016/j.tust.2025.106770","url":null,"abstract":"<div><div>A reasonable prediction of surface settlement caused by tunnel excavation in complex environments is of great importance for ensuring the safety of surface structures. The introduction of machine learning (ML) and deep learning (DL) provides a new solution for surface settlement prediction. A novel optimisation method to enhance the performance of ML and DL is proposed. This method employs an autoregressive moving average (ARMA)-based Time-series Decomposition, abbreviated as ATD model. First, the surface settlement time-series was decomposed into two subseries features, construction-caused and stochastic-caused surface settlement, using the ATD model. Second, four ML algorithms and five DL algorithms based on unsupervised learning were introduced to predict the two subsequences. Then, the prediction results of the sub-sequences were linearly combined to obtain the predicted values of surface subsidence. The efficacy of each ML and DL algorithm was markedly enhanced following the implementation of the ATD model outlined in this study. The average 1-R² decreased by 32.62 %, whereas the Root Mean Square Error (RMSE), Mean Absolute Error (MAE), and Mean Absolute Percentage Error (MAPE) exhibited mean reductions of 19.91 %, 23.37 %, and 16.44 %, respectively. The critical error value was introduced for the analysis of the frequency of the occurrence of model errors. The results demonstrate that the utilisation of the ATD model can significantly reduce the prediction error associated with ML and DL for surface settlement prediction.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"164 ","pages":"Article 106770"},"PeriodicalIF":6.7,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144243348","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":"Investigation on the force transmission performance between segmental rings of super-large cross-section shield tunnels","authors":"Wenqi Guo ,&nbsp;Kun Feng ,&nbsp;Haixing Mu ,&nbsp;Jiaqi Li ,&nbsp;Yili Zhou ,&nbsp;Chuan He","doi":"10.1016/j.tust.2025.106779","DOIUrl":"10.1016/j.tust.2025.106779","url":null,"abstract":"<div><div>With the development of shield tunnels towards larger cross-sections and more complex joint structures, the longitudinal–transverse coupling effect of segment structures has become increasingly significant. Assessing the force transmission effect between segmental rings is crucial for optimizing segment structures design. A full-scale loading test was conducted on staggered joint assembly segment structures to investigate the deformation of the segments, deformation of the joints, mechanical behavior of the reinforcement and bolts, force transmission behavior between segmental rings, as well as the failure progression and patterns of the segment structures. Based on this, a detailed 3D numerical calculation model, calibrated through full-scale tests, was utilized to analyze the effects of longitudinal pressure on the deformation of segment structures and the moment transfer coefficient between segmental rings. The findings indicate that the upper half-ring segment exhibited greater deformation compared to the lower half-ring segment, while both were larger than that of the middle ring segment. The longitudinal joint opening and circumferential joint dislocation in the upper half-ring segment underwent five distinct phases, whereas the lower half-ring segment experienced only three stages of variation. The difference in the mechanical behavior of longitudinal bolts resulted in greater shear stiffness for the circumferential joint under ordinal shear conditions compared to reverse shear. The evolution of the moment transfer coefficient occurred in four distinct phases. The contact between mortise and tenon markedly increased this coefficient, while plastic hinge formation in the segment structures led to a sharp decline. Additionally, the maximum moment transfer coefficient showed a positive relationship with longitudinal pressure, ranging from 0.4 to 0.7 when the pressure was between 0 and 3.0 MPa.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"164 ","pages":"Article 106779"},"PeriodicalIF":6.7,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144243347","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":"On-line monitoring of underground workings stability with use of innovative inclinometric method – Case study from Polish copper mines","authors":"Lech Stolecki ,&nbsp;Krzysztof Fuławka ,&nbsp;Tomasz Osadczuk","doi":"10.1016/j.tust.2025.106796","DOIUrl":"10.1016/j.tust.2025.106796","url":null,"abstract":"<div><div>The threat of loss of stability of underground workings is one of the most serious dangers accompanying underground mineral exploitation. Over the years, as the depth of the deposits increased and working conditions deteriorated, the scale of the threat increased, translating into a serious risk to the life and health of the mining crew. In order to increase work safety and at the same time ensure the possibility of effective exploitation, it is necessary to implement new, autonomous monitoring systems that inform the mining operator on an ongoing basis about possible threats. In recent years, many geomechanical measurement systems have been developed. Particular attention was paid to instrumented rock bolts that can measure stresses and deformations in the immediate roof in real time. Unfortunately, despite many advantages, devices of this type provide information only about a specific threat state, and without the installation of several devices in one place, they do not enable spatial monitoring. An inclinometer system may be a milestone in the development of geomechanical systems, which enables the measurement of deformations of roof layers in real time, and the nature of the measurements translates into the possibility of conducting spatial monitoring within the excavation using one device. This article presents the results of many years of work on the development of an inclinometric system adapted to work in underground mines exploiting deposits using a room and pillar mining method. The assumptions of the system as well as the rock failure criterion developed based on pilot measurements were described. Also the results of a multi-month post-measurement campaign conducted in all three underground copper mines in Poland were presented. As shown by previous observations, the newly developed inclinometric system for monitoring the stability of workings is characterized by measurement stability and reliability of the obtained results. Therefore, it can be successfully used in underground mines facing the risk of collapse to monitor the stability of mines in real time from the control room level.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"164 ","pages":"Article 106796"},"PeriodicalIF":6.7,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144243350","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":"The dynamic response and crack propagation mechanism of deep jointed rocks under transient unloading","authors":"Xiaoqing Wei ,&nbsp;Kaiwen Song ,&nbsp;Yi Luo ,&nbsp;Junhong Huang ,&nbsp;Tingting Liu","doi":"10.1016/j.tust.2025.106795","DOIUrl":"10.1016/j.tust.2025.106795","url":null,"abstract":"<div><div>Aimed at the full-face blasting excavation of a deep circular tunnel, this research explores the dynamic response and crack propagation mechanism of jointed rocks under transient unloading. Based on the plane strain assumption, the theoretical mechanical behavior of rocks under transient unloading was analyzed. Model tests were conducted using a self-developed test system to investigate the effects of joint length and joint spacing on the transient unloading process. The results show that joints have significant reflection and transmission effects on stress waves. Compared with the condition without joints, the presence of joints increases strain reduction on the reflected side by approximately 16.5%, indicating enhanced wave reflection, and decreases strain reduction on the transmitted side by approximately 25.8%, indicating weakened wave transmission. Longer joints result in stronger reflection effects at the joint center, and smaller joint spacing may induce tensile strain in the surrounding rock. As for crack propagation, two primary crack initiation modes were observed: initiation at the ends and at the middle of the joints. These findings enhance the understanding of dynamic response and crack propagation in jointed rock masses under transient unloading, and provide a theoretical basis for related engineering applications.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"164 ","pages":"Article 106795"},"PeriodicalIF":6.7,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144243346","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":"Underground pipeline inspection and monitoring in mountainous areas: A state-of-the-art review and future perspectives","authors":"Xianghuan Luo ,&nbsp;Yu Zhao ,&nbsp;Mingxiao Li ,&nbsp;Hang Zhou ,&nbsp;Fuming Wang ,&nbsp;Yanliang Du ,&nbsp;Wenyu Jiang ,&nbsp;Jiasong Zhu ,&nbsp;Yahong Zhao","doi":"10.1016/j.tust.2025.106783","DOIUrl":"10.1016/j.tust.2025.106783","url":null,"abstract":"<div><div>Pipeline accidents are frequently reported in mountainous areas, where conventional inspection and monitoring methods often fall short for complex terrain environment and various pipeline defects. This study conducts a thorough evaluation of characteristics, challenges, current research status, and potential enhancements for pipeline inspection and monitoring in mountainous areas. It categorises the review into three main sectors: external inspection, in-pipe inspection, and integrated environment-geology-pipeline monitoring, each tailored to overcome the obstacles posed by rugged terrains. External inspections, hindered by difficult terrain and environmental hazards, benefit from the use of drones equipped with high-resolution sensors. In-pipe inspections necessitate robust, adaptable robots capable of navigating the harsh conditions typical of mountainous pipelines. Integrated monitoring synthesizes these techniques into a unified system that leverages real-time data analytics, robust sensor materials, and sophisticated algorithms to optimize sensor placement and performance. The paper highlights state-of-the-art developments and suggests future advancements should concentrate on improving the durability and efficiency of these technologies and enhancing the integration with artificial intelligence. These improvements are essential for ensuring the reliability, efficiency, and safety of pipeline operation in challenging environments.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"164 ","pages":"Article 106783"},"PeriodicalIF":6.7,"publicationDate":"2025-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144243349","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":"Experiment-based study on three dimensional seepage at tunnel junction of parts constructed by different methods","authors":"Helin Fu ,&nbsp;Kaixun Hu ,&nbsp;Yimin Wu ,&nbsp;Weiguo He","doi":"10.1016/j.tust.2025.106773","DOIUrl":"10.1016/j.tust.2025.106773","url":null,"abstract":"<div><div>Composite construction methods may be adopted in some underwater tunnels due to complex geological conditions. However, the seepage field at the junction between parts constructed by different methods has been rarely reported. This study used the Pearl River Estuary Tunnel as a case study to conduct model experiments on the connection part and its adjacent mining and shield parts, which have different drainage systems. Through model experiments, the study explored the variation laws of water inflow and external water pressure on the tunnel lining. The experimental results were validated against numerical simulations. The results indicate that, longitudinally, the junction experiences pressure fluctuations due to variations in construction methods and tunnel cross-sectional dimensions. A logistic fit of the experimental data shows that fluctuations range from 12 to 21 m in the mining part and from 27 to 42 m in the shield part. The longitudinal distributions indicate that water pressure remains stable in the shield part, while in both the connection and mining parts it is influenced by the drainage pipes. Transversely, water pressure increases from the arch crown to the arch bottom, forming an approximately circular distribution. Both water pressure and inflow increase linearly with rising water levels. A comparison between experimental and simulation results shows a relative error of less than 9 %, confirming the accuracy of the experimental model. The study’s findings provide deeper insight into the seepage field at the junction of underwater tunnel parts, with implications for the design and construction of similar projects.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"164 ","pages":"Article 106773"},"PeriodicalIF":6.7,"publicationDate":"2025-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144243455","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}