Yang Gao , Yuhao Fang , Lunlun Gong , Shenlin Yang , Changfa Tao , Wei Xu
{"title":"The experimental study on the flame extension length and maximum temperature of ceiling jet flame in the curved tunnel","authors":"Yang Gao , Yuhao Fang , Lunlun Gong , Shenlin Yang , Changfa Tao , Wei Xu","doi":"10.1016/j.tust.2025.106571","DOIUrl":"10.1016/j.tust.2025.106571","url":null,"abstract":"<div><div>This paper investigated the extension length and maximum temperature of ceiling jet flame with different fire source locations within the curved tunnel. A series of experiments were conducted in a 1:15 reduced-scale tunnel with four different bending radians. Two nozzle diameters (2 and 4 mm) and four fire source positions were considered, while the propane was used as the fuel gas. The experimental results reveal distinct extension characteristics of ceiling jet flame in both the transverse and longitudinal directions. Dimensionless correlations for the transverse and longitudinal extension length of ceiling jet flame have been developed. Additionally, the variation in maximum temperature under different tunnel bending radians was analyzed based on the flame geometry model, which leads to the establishment of theoretical model for predicting the maximum temperature.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"161 ","pages":"Article 106571"},"PeriodicalIF":6.7,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632068","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}
Youjun Xu , Zhengxi Zhang , Chao Zhang , Xin Han , Tianyu Liu , Xu Zhang
{"title":"Analysis of longitudinal deformation of existing rectangular pipe jacking tunnel caused by shield tunnel undercrossing","authors":"Youjun Xu , Zhengxi Zhang , Chao Zhang , Xin Han , Tianyu Liu , Xu Zhang","doi":"10.1016/j.tust.2025.106532","DOIUrl":"10.1016/j.tust.2025.106532","url":null,"abstract":"<div><div>The existing rectangular pipe jacking tunnel is prone to deform after the construction of the new nearby shield tunnel, resulting in longitudinal uneven settlement, water leakage, and other ailments that could jeopardize the structure’s safety. The safety of the existing rectangular pipe jacking tunnel is in jeopardy in order to prevent the excessive deformation of the tunnel following the construction of the new shield tunnel. This paper proposes the foundation stiffness function model and SP-T model to describe the settlement curve of the new shield tunnel to the existing rectangular pipe jacking tunnel using the first phase project of Hohhot Rail Transit Line 2 in Inner Mongolia as an example. The model is more coincidental than the original Pasternak-Timoshenko model considering the distribution in soil caused by the excavation of a new tunnel because it takes into account the change in foundation stiffness based on the Pasternak foundation. The findings demonstrate the consistency between the field data results and the prediction results derived from the analysis method presented in this paper. The further parametric study examined some influences on the construction of a new shield tunnel that affects already-existing pipe jacking tunnels. These studies include equivalent longitudinal bending and shear stiffness, as well as the location and angle of the new tunnel in relation to the existing rectangular pipe jacking tunnel. In addition to highlighting the impact of equivalent shear stiffness on the existing rectangular pipe jacking tunnel, the impact of equivalent longitudinal bending stiffness and equivalent longitudinal shear stiffness on settlement is discussed in the article.<!--> <!-->This paper’s research methodology can not only forecast the new shield tunnel’s longitudinal settlement deformation beneath the existing rectangular pipe jacking tunnel, but it can also generate fresh concepts for investigating related issues.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"161 ","pages":"Article 106532"},"PeriodicalIF":6.7,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632067","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}
Qianfeng Xiao, Yang Wang, Yajing Li, Leilei Jin, Wenxi Fu, Fei Ye
{"title":"Theoretical and numerical study of the failure mechanism and minimum safety thickness of water-resistant rock mass in layered karst tunnels","authors":"Qianfeng Xiao, Yang Wang, Yajing Li, Leilei Jin, Wenxi Fu, Fei Ye","doi":"10.1016/j.tust.2025.106586","DOIUrl":"10.1016/j.tust.2025.106586","url":null,"abstract":"<div><div>Excavating layered karst tunnels often triggers water and mud inrushes, posing serious risks to life and property. This paper examines the effect of layered rock structures on the failure mechanism and minimum safety thickness of water-resistant rock mass. First, mechanical models for horizontally and vertically layered water-resistant rock mass are established. Utilizing the Mohr-Coulomb criterion and the minimum potential energy principle, analytical solutions for the minimum safety thickness of both models are derived. Next, the discrete element method (DEM) is used to analyze fracture propagation, force chain interactions, and displacement distribution in both horizontally and vertically layered water-resistant rock mass. Finally, based on theoretical and numerical analyses, failure modes of layered water-resistant rock mass with different strata inclinations are proposed: flexural-tensile failure in vertically layered rock, creep-sliding tensile failure in horizontally layered rock, and the combined toppling-bending tensile failure mode in inclined layered rock. The results indicate that (1) the variation curve of crack numbers in a water-resistant rock mass can be categorized into four distinct stages: Stage I, the fracture development and rock mass damage stage; Stage II, the fracture equilibrium and energy absorption stage; Stage III, the large deformation and rapid fracture progression stage; and Stage IV, the complete failure stage. (2) Shear failure occurs along the structural plane within the horizontally layered water-resistant rock mass. Tensile rupture failure occurs in the horizontally layered rock mass when the shear strength of the structural plane exceeds the tensile strength of the rock mass. (3) Bending failure occurs in the vertically layered water-resistant rock mass. The force chain within the rock mass at the tunnel face end undergoes tensile stress, whereas at the cavity end, the force chain is subjected to compressive stress.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"161 ","pages":"Article 106586"},"PeriodicalIF":6.7,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143637594","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}
Diyang Chen , Yanhao Chen , Zongqing Zhou , Wenfeng Tu , Liping Li
{"title":"Study on internal rise law of fracture water pressure and progressive fracture mechanism of rock mass under blasting impact","authors":"Diyang Chen , Yanhao Chen , Zongqing Zhou , Wenfeng Tu , Liping Li","doi":"10.1016/j.tust.2025.106545","DOIUrl":"10.1016/j.tust.2025.106545","url":null,"abstract":"<div><div>Groundwater and its storage structures are widespread, leading to frequent water inrush disasters during tunnel construction, which severely compromise safety and efficiency. Blasting disturbances cause rock fissures to expand and connect, leading to instability and failure. However, the mechanisms behind tunnel water inrush caused by blasting, especially the dynamic changes in water pressure within fissures, remain insufficiently understood. This study addresses water inrush caused by fractured rock mass failure under dynamic disturbance, focusing on deep, high-pressure tunnels with complex geological conditions. It systematically explores how blasting impacts water pressure in fissures, using safe and efficient simulation methods combined with dynamic damage tests on water-bearing fractures. The research examines how blasting-induced water pressure changes affect rock stability. The findings reveal that the increase in water pressure caused by blasting provides a theoretical basis for understanding water inrush mechanisms and disaster criteria. Additionally, this study overcomes the limitations of traditional explosive tests by achieving safe, controlled, and efficient blasting simulations. It advances the analysis of water-bearing fractures from qualitative to quantitative characterization, offering new insights and methods for preventing water inrush disasters during tunnel construction.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"161 ","pages":"Article 106545"},"PeriodicalIF":6.7,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632065","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}
Gang Zheng , Huimin Qiu , Tianqi Zhang , Huanyu Cheng , Yu Diao , Ke Wang
{"title":"Modelling ground and tunnel response to water-soil gushing in stratified soil","authors":"Gang Zheng , Huimin Qiu , Tianqi Zhang , Huanyu Cheng , Yu Diao , Ke Wang","doi":"10.1016/j.tust.2025.106583","DOIUrl":"10.1016/j.tust.2025.106583","url":null,"abstract":"<div><div>In silty (fine) sand aquifer, water-soil gushing (WSG) of shield tunnel may occur, causing structural damage and even collapse. A comprehensive understanding of the mechanism behind ground displacement and tunnel deformation during WSG in stratified soil was required for guiding disaster-relief in practice. In this article, the responses of ground and shield tunnel to WSG in stratified soil were investigated using a material-point method (MPM). First, a typical case of WSG in stratified soil was studied. By comparing the results with those of WSG in a homogeneous sand, both the ground and tunnel responses to WSG in a stratified soil were clarified. It was found that in stratified soil, the tunnel lining may deform first and then became stable, while in homogeneous sand, the tunnel deformation was shown to continuously develop with time due to unremitting soil loss. Then, the effects of the WSG locations, the sand layer position to tunnel, the layers number and permeability of clay and the discharge rate on WSG were further analyzed.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"161 ","pages":"Article 106583"},"PeriodicalIF":6.7,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143627652","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}
Man Yuan , Shuaibin Sun , Yingke Liu , Tengrui Yang , Chao Li , Yue Niu , Xiaojiang Wen
{"title":"Modeling and control method of coal instability around cavity under water jet impact loading","authors":"Man Yuan , Shuaibin Sun , Yingke Liu , Tengrui Yang , Chao Li , Yue Niu , Xiaojiang Wen","doi":"10.1016/j.tust.2025.106574","DOIUrl":"10.1016/j.tust.2025.106574","url":null,"abstract":"<div><div>In the process of Hydraulic jet cavity completion (HJCC), the elastic energy and gas expansion energy endowed in the coal around cavity can be instantly released under the strong disturbance of the water jet and cause dynamic disasters. Currently, the influence mechanisms of external disturbance and gas desorption on the cavity instability are unclear, and the technical methods to ensure cavity stability cannot be obtained. In this paper, a cavity instability model under water jet impact loading was derived, which considered both the dynamic stress field and the gas pressure field of the coal, and the control method was given by studying the influence mechanisms of the jet (or coal seam) parameters on the energy leading to instability. The results show that the jet pressure and ground stress affect the elastic energy by determining the effective stress distribution within the energy release zone. The initial gas pressure affects the gas expansion energy by determining the ratio of free to adsorbed gas pressure for the same desorption time. Besides, the jet pressure determines the dominant energy of cavity instability. Finally, the guidelines for “Pressurization by step” were proposed to ensure cavity stability. The results can ensure the safety of HJCC’s operation.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"161 ","pages":"Article 106574"},"PeriodicalIF":6.7,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143621532","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":"Seismic ahead-prospecting method based on delayed blasting excitation in the tunnel face: A case study","authors":"Chao Jia , Shuai Cheng , Liping Li , Yanhao Chen","doi":"10.1016/j.tust.2025.106577","DOIUrl":"10.1016/j.tust.2025.106577","url":null,"abstract":"<div><div>Advanced geological detection technology plays a crucial role in identifying adverse geological conditions along tunnel routes, providing early warnings for potential disasters such as water inrush, and ensuring construction safety. Among these technologies, the seismic wave method is widely used for predicting geological conditions in tunneling projects. However, traditional seismic wave approaches often rely on additional seismic source excitation, which disrupts construction activities and slows progress. To address these limitations, this paper proposes an innovative seismic wave ahead-prospecting method that utilizes the seismic waves generated by blasting at the tunnel face as the seismic source, thereby eliminating the need for separate seismic source excitation. This study proposes a delayed blast seismic source excitation method, which effectively avoids the disordered reception of the reflected waves and successfully extracts the effective reflected waves. Additionally, an observation system tailored for large-charge blasting in tunnels is designed, ensuring equipment safety and efficient data collection. Numerical simulation results demonstrate that blasting at the tunnel face serves as an effective seismic source for detecting geological anomalies, such as vertical interfaces. The research presents an innovative concept for rapidly constructing tunnels utilizing the drilling and blasting method.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"161 ","pages":"Article 106577"},"PeriodicalIF":6.7,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143621533","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}
Guanhong Lu , Lei Kou , Pei Niu , Gaohang Lv , Xiao Zhang , Jian Liu , Quanyi Xie
{"title":"GPRTransNet: A deep learning–based ground-penetrating radar translation network","authors":"Guanhong Lu , Lei Kou , Pei Niu , Gaohang Lv , Xiao Zhang , Jian Liu , Quanyi Xie","doi":"10.1016/j.tust.2025.106557","DOIUrl":"10.1016/j.tust.2025.106557","url":null,"abstract":"<div><div>Ground-penetrating radar (GPR) is an essential nondestructive testing tool widely used in tunnel and road defect detection, underground object detection, and unstructured terrain perception. Currently, most GPR inversion methods based on deep learning use convolutional neural networks, which have limitations such as incomplete feature extraction and low accuracy. Inspired by advancements in the NLP field, this paper proposes a novel deep learning framework for GPR called GPRTransNet. The algorithm introduces a “wave to permittivity” translation architecture, leveraging the “memory” function of recurrent neural networks to translate GPR data into permittivity model images, similar to language translation. In addition, the inclusion of the attention mechanism significantly enhances the network’s ability to represent defects in complex scenarios, resulting in outstanding translation performance. GPRTransNet has been validated on a simulated dataset, with the newly proposed G-SSIM evaluation metric showing that the permittivity similarity of GPRTransNet-Lite reaches 98.47% and that of GPRTransNet-Pro is 99.26%. Furthermore, GPRTransNet demonstrates good translation performance on real data. Experimental results show that the results of GPRTransNet’s translation of GPR are satisfactorily matched.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"161 ","pages":"Article 106557"},"PeriodicalIF":6.7,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143610756","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}
Chao Zhao , Wenping Gong , C. Hsein Juang , Huiming Tang , Zhongqiang Liu , Xinli Hu
{"title":"Probabilistic performance analysis of longitudinal tunnels based on coupled characterization of stratigraphic and geo-properties uncertainties","authors":"Chao Zhao , Wenping Gong , C. Hsein Juang , Huiming Tang , Zhongqiang Liu , Xinli Hu","doi":"10.1016/j.tust.2025.106552","DOIUrl":"10.1016/j.tust.2025.106552","url":null,"abstract":"<div><div>The geological model (including stratigraphic configuration and geo-properties) of shield tunnels can be varied strongly along the tunnel alignment, due to the large longitudinal length of tunnels and spatial variability of geological bodies. Meanwhile, the geological model uncertainty can exert a significant influence on the evaluated tunnel behavior (e.g., tunnel longitudinal behavior and circumferential behavior of tunnel segment rings). However, the influence of stratigraphic and geo-properties uncertainties on the tunnel behavior has not been revealed. To this end, this paper presents a novel framework for the tunnel behavior analysis considering stratigraphic and geo-properties uncertainties. The geological model is sampled utilizing a conditional random field approach in the proposed framework, considering spatial variabilities of strata and geo-properties simultaneously. With generated geological models as inputs, the tunnel longitudinal behavior is estimated using a finite element method; then, the circumferential behavior of tunnel segment rings is evaluated using an analytical solution. The effectiveness of this framework is demonstrated by a case study of a tunnel in China. Further, a comparative analysis is undertaken based upon the monitoring data of the tunnel behavior to investigate the influence of uncertainty sources on the tunnel behavior, through which the significance of the new framework can be illustrated.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"161 ","pages":"Article 106552"},"PeriodicalIF":6.7,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143611373","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}
Yu Sun , Chenguang Guo , Jianzhuo Zhang , Binghao Lu , Guochao Zhao
{"title":"Analysis of the influence of laser process parameters on cutting performance of laser-assisted disc cutter","authors":"Yu Sun , Chenguang Guo , Jianzhuo Zhang , Binghao Lu , Guochao Zhao","doi":"10.1016/j.tust.2025.106548","DOIUrl":"10.1016/j.tust.2025.106548","url":null,"abstract":"<div><div>Laser-assisted disc cutter cutting offers a promising approach to enhance the cutting performance of hard rock by inducing thermal stress, which weakens the rock’s strength. In this study, experiments and numerical simulations were conducted to establish the relationship between laser-induced thermal stress and rock strength weakening. The effects of laser power, radiation distance, and strafing speed on the weakening of rock strength and energy consumption in granite were investigated, providing an optimal process window for laser-assisted disc cutter cutting. An experimental system for synchronous laser-disc cutter cutting was developed to examine the influence of laser parameters on cutting performance. Results indicate that the weakening of granite strength is closely associated with laser-induced thermal stress. Higher laser power, coupled with lower strafing speed and shorter radiation distance, significantly enhances thermal cracking in the granite, leading to more effective induction of thermal stress and, consequently, greater weakening of rock strength. The maximum reduction in rock strength observed was 41.34 %. However, excessive heat absorption by the granite can cause melting and evaporation, increasing energy loss. Thus, it is crucial to determine an optimal balance between maximum strength reduction and minimal energy consumption for granite in laser-assisted disc cutter cutting. Compared with conventional rock cutting, laser-assisted disc cutter cutting reduces normal cutting force from 11.488 kN to 9.638 kN, a decrease of 16 %. Additionally, normal vibration acceleration is reduced from 18.881 mm/s<sup>2</sup> to 14.432 mm/s<sup>2</sup>, representing a 23 % reduction. The volume of rock broken increases from 13.50 cm<sup>3</sup> to 16.50 cm<sup>3</sup>, reflecting a 22.22 % improvement. These findings demonstrate that laser-assisted disc cutter cutting reduces the load impact on the disc cutter and enhances rock-cutting volume. Further analysis of lithological energy under laser-assisted conditions is essential for improving the cutting performance of Tunnel Boring Machine (TBM).</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"161 ","pages":"Article 106548"},"PeriodicalIF":6.7,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143610758","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}