Article
Engineering, Civil
Cheng Cheng, Pengjiao Jia, Pengpeng Ni, Yingchao Wang, Wen Zhao, Yongping Guan, Bo Lu
Summary: In this study, the finite difference method is used to investigate the face stability of longitudinally inclined shield tunnel in dense sand strata. A novel two-dimensional failure mechanism is proposed, and a scale factor is introduced to quantify the three-dimensional behavior. The improved 2D failure mechanism provides reasonable prediction for longitudinally inclined tunnel.
TRANSPORTATION GEOTECHNICS
(2023)
Article
Engineering, Mechanical
Minghui Sun, Qixiang Yan, Yunhui Qiu, Caihou Xu, Chaofan Yao, Zimiao Zhang, Jupei Yang
Summary: During shield tunneling, accurately revealing the collapse mechanism and evaluating the minimum required support pressure are crucial for tunnel face stability. This study proposes a practical strategy to consider the strain softening effect in finite element simulations and introduces a novel method for evaluating the minimum required support pressure. The results show that the tunnel face collapse process is accompanied by local stratum strain softening and the proposed method effectively assesses the minimum support pressure for construction safety concerns.
ENGINEERING FAILURE ANALYSIS
(2023)
Article
Computer Science, Interdisciplinary Applications
Pooyan Jafari, Ahmad Fahimifar
Summary: This paper investigates the face stability of rectangular shield-driven tunnels in undrained clays, where the undrained shear strength increases linearly with depth. Two new failure mechanisms are proposed based on the translational movement of rigid blocks and continuous deformation of soil mass. The analytical solutions are compared with numerical simulations and existing approaches in the literature to evaluate their validity. The critical support pressures obtained from the analytical models are consistent with numerical simulations, and simple design formulas are provided for practical use. Parametric studies explore the impact of different geometrical and geotechnical parameters on tunnel face stability.
COMPUTERS AND GEOTECHNICS
(2022)
Article
Chemistry, Multidisciplinary
Miao Yu, Wei Liu, Ben Wu, Jiajia Yan, Penglu Gan
Summary: This paper proposes a theoretical model for the stability analysis of a box tunnel face in non-cohesive soils. The model takes into consideration the uneven distribution of support pressure caused by multiple cutter heads and screw conveyors. Through parametric analysis and numerical comparisons, the rationality of the proposed model in predicting collapse geometry is verified.
APPLIED SCIENCES-BASEL
(2022)
Article
Construction & Building Technology
Wei Li, Chengping Zhang, Zhibiao Tan, Mengshuo Ma
Summary: This study evaluates the face stability of a shield tunnel excavated in saturated soils under steady seepage flow conditions through numerical simulations and theoretical analysis. An analytical solution for the hydraulic head distribution ahead of the tunnel face is proposed, and it is found to agree well with numerical analysis and existing studies. Additionally, it is suggested that neglecting the permeability anisotropy of soils may result in an overestimation of the required face pressure.
TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY
(2021)
Article
Engineering, Civil
Wei Li, Chengping Zhang, Shiqin Tu, Wen Chen, Mengshuo Ma
Summary: This paper investigates the influence of inclined strata on face stability of shield tunnels through theoretical analysis and numerical simulation. A three-dimensional kinematic failure mechanism considering the intersection between inclined soil interface and tunnel face is constructed using the spatial discretization technique. An analytical solution for critical support pressure is obtained and compared with numerical results to verify its accuracy and effectiveness. The effects of dip and position of inclined strata on face stability are thoroughly studied. The proposed failure mechanism can be used as a reference for face stability analysis in inclined strata.
Article
Construction & Building Technology
T. Vo-Minh, L. Nguyen-Son, G. Nguyen-Van, T. Thai-Phuong
Summary: This paper presents an isogeometric analysis (IGA) based on Be ' zier extraction to investigate the stability of a circular tunnel in cohesive-frictional soils subjected to uniform surcharge loading. Through upper bound limit analysis, design tables and charts are generated for various soil properties, internal friction angles and ratios of tunnel cover to tunnel diameter to prove the reliability and efficiency of the present method.
TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY
(2021)
Article
Engineering, Civil
Xiaobin Ding, Kang Li, Yuxuan Xie, Shuzhuo Liu
Summary: The new 3D log-spiral model LS-M model accurately determines the minimum support pressure on the tunnel face of large shield-driven tunnels, providing more realistic collapse zone geometry than traditional wedge models. It has acceptable accuracy and simpler implementation compared to limit equilibrium analysis, and shows good agreement with previous studies and numerical analysis results.
Article
Engineering, Civil
Xiaobin Ding, Kang Li, Yuxuan Xie, Shuzhuo Liu
Summary: A new 3D log-spiral model (LS-M model) is proposed for determining the minimal support pressure on the tunnel face of a large shield-driven tunnel in rock-soil interface (RSI) composite formations. The proposed model provides a collapse zone with more realistic geometry compared to traditional wedge models and has simpler implementation compared to limit equilibrium analysis. It has been validated through comparisons with previous studies and 3D numerical analysis.
Article
Construction & Building Technology
Shiqin Tu, Wei Li, Chengping Zhang, Wen Chen
Summary: This article improves a 3D rotating rigid body collapse mechanism based on limit analysis using discretization technique, in order to evaluate the stability of tunnel face when shield tunnel is excavated along inclined layered soil. The results show that the existence of inclined stratum results in asymmetric failure mechanism of tunnel face and variation of active failure pressure.
TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY
(2023)
Article
Physics, Particles & Fields
Roberto Casadio
Summary: A simple quantum description is presented for the gravitational collapse of a ball of dust, which excludes states with a width arbitrarily smaller than the gravitational radius of the matter source. This study supports the conclusion that black holes are macroscopic extended objects and briefly comments on the relevance to the ultraviolet self-completion of gravity and the connection with the corpuscular picture of black holes.
EUROPEAN PHYSICAL JOURNAL C
(2022)
Article
Computer Science, Interdisciplinary Applications
Yu Zhang, Lianjin Tao, Xu Zhao, Heng Kong, Fei Guo, Jin Bian
Summary: In this paper, a new analytical model is proposed to predict the limit support pressure acting on the tunnel face in deep-buried shield tunnels in dry cohesionless soils. The rationality and effectiveness of the proposed model were verified by comparing with model tests, existing theoretical methods, and numerical model. The study also discussed the significant effects of the internal friction angle of soil on the tunnel state and limit support pressure.
COMPUTERS AND GEOTECHNICS
(2022)
Article
Engineering, Marine
Shanglong Zhang, Xuansheng Cheng, Lei Qi, Xinhai Zhou
Summary: This paper studies the influence of high water pressure seepage on the stability of large diameter shield tunnel face in soft clay. The theoretical solution and verification method for the limit support force under different water levels are proposed. The results show that seepage force is the main component of the total limit support force, and water levels and soil internal friction angles have a significant impact on face stability.
Article
Construction & Building Technology
Maosong Huang, Yishan Li, Zhenhao Shi, Xilin Lu
Summary: This paper presents a limit equilibrium model for shield face stability, emphasizing the effects of ground heterogeneity and seepage flow. The model considers a new wedge mechanism with changing inclination across soil layers. Coupled pore fluid flow and stress finite element simulations are conducted to evaluate the model under different geological and hydrogeological conditions, showing its suitability for assessing necessary face pressures.
TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY
(2022)
Article
Computer Science, Interdisciplinary Applications
Wei Liu, Ben Wu, Peixin Shi, Guoqing Cai
Summary: This paper investigates the passive instability of the working face of large-diameter shield tunneling in frictional soils by developing a new mechanism, which outperforms previous translational mechanisms in predicting critical support pressure and associated failure mode. The current solution is validated by comparing with previous centrifuge tests, indicating the accuracy of the proposed composite mechanism.
COMPUTERS AND GEOTECHNICS
(2021)
Article
Engineering, Geological
H. Alhajj Chehade, D. Dias, M. Sadek, O. Jenck, F. Hage Chehade
Summary: This paper examines the seismic behavior of earth retaining walls using the upper bound theorem of limit analysis and discretization technique, with pseudo-static approach to model seismic effects. The extended methodology proposed is validated against conventional limit analysis results and a parametric study is conducted to identify the effects of key parameters on required reinforcement strength.
Article
Chemistry, Multidisciplinary
Hung Van Pham, Daniel Dias
Summary: This paper investigates the behavior of rigid inclusion-improved soil under different loading conditions through laboratory tests and numerical simulation. The study shows that the HYP model can better simulate the soil arching mechanism, providing good agreement with experimental data.
APPLIED SCIENCES-BASEL
(2021)
Article
Engineering, Geological
Hoang-Giang Bui, Jelena Ninic, Ngoc-Anh Do, Daniel Dias, Guenther Meschke
Summary: This technical note presents a consistent finite element formulation for tunnel linings design by introducing a variational consistently linearized formulation to consider nonlinear interaction between lining structure and ground. The proposed VHRM model allows for more efficient solution of nonlinear system equations and is applicable for various types of finite elements.
INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS
(2022)
Article
Chemistry, Multidisciplinary
Chi Thanh Nguyen, Ngoc Anh Do, Daniel Dias, Van Vi Pham, Gospodarikov Alexandr
Summary: This paper presents an improved HRM method for estimating the internal forces induced in square and rectangular tunnel linings. The results show that the lateral earth pressure coefficient and the tunnel lining flexibility ratio have a significant impact on the internal forces induced.
APPLIED SCIENCES-BASEL
(2022)
Article
Engineering, Civil
Van Vi Pham, Ngoc Anh Do, Daniel Dias, Chi Thanh Nguyen, Van Kien Dang
Summary: This paper focuses on the different behavior of sub-rectangular tunnels under static loading compared to circular and rectangular tunnels. It provides designers with information to choose the appropriate tunnel shape solution and investigates the influence of various parameters on tunnel behavior.
TRANSPORTATION INFRASTRUCTURE GEOTECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Xiancheng Mei, Chuanqi Li, Qian Sheng, Zhen Cui, Jian Zhou, Daniel Dias
Summary: This study proposes a novel rubber-sand concrete (RSC) as an aseismic material and uses an artificial intelligence model, the back propagation neural network (BPNN), to predict its uniaxial compressive strength (UCS). The results show that the LSO-BPNN hybrid model has the best prediction capability. Sensitivity analysis reveals that rubber and sand have the greatest impact on UCS prediction.
MECHANICS OF ADVANCED MATERIALS AND STRUCTURES
(2023)
Article
Engineering, Geological
Dianchun Du, Daniel Dias, Ngocanh Do
Summary: This paper presents a simple and effective calculation process for analyzing the interaction between rock mass and support structure in tunnel lining design. By considering the stress redistribution and convergence caused by delayed installation, the method combines the hyperstatic reaction method and convergence confinement method. The validity of the method is verified through the comparison of results, and the influence of various parameters is discussed.
PROCEEDINGS OF THE INSTITUTION OF CIVIL ENGINEERS-GEOTECHNICAL ENGINEERING
(2022)
Article
Chemistry, Multidisciplinary
Jiamin Zhang, Daniel Dias, Qiujing Pan, Chunjing Ma, Cristina de Hollanda Cavalcanti Tsuha
Summary: This paper presents numerical simulations to assess the long-term performance of thermo-active pile systems in tropical environments for different energy demands, highlighting the significance of groundwater flow in improving thermal balance.
APPLIED SCIENCES-BASEL
(2022)
Article
Chemistry, Multidisciplinary
Duc Phi Do, Xiangfeng Guo, Daniel Dias
Summary: In this paper, the effects of uncertainties of time-dependent rock behavior and anisotropy of initial stress state on the stability of a tunnel supported by a double flexible/concrete liner are investigated. Subset simulation and Sobol global sensitivity analysis are used to estimate the failure probability of the tunnel supports and quantify the importance of different random parameters. The results show that considering the anisotropy of initial stresses increases the failure probability, especially in the concrete support elements. Furthermore, the parameters of initial stresses are found to be of main importance for both liners according to the Sobol indices.
APPLIED SCIENCES-BASEL
(2022)
Article
Chemistry, Multidisciplinary
Chuanqi Li, Jian Zhou, Daniel Dias, Yilin Gui
Summary: A novel machine learning model, KELM-GWO, was proposed for predicting rock compressive strength, with the best performance indices. Porosity was identified as the most important parameter for predicting UCS using the mean impact value (MIV) technique.
APPLIED SCIENCES-BASEL
(2022)
Article
Chemistry, Physical
Chuanqi Li, Xiancheng Mei, Daniel Dias, Zhen Cui, Jian Zhou
Summary: This paper proposes a novel hybrid artificial neural network model optimized using a reptile search algorithm with circle mapping to predict the compressive strength of rice husk ash concrete. The proposed model achieved the most satisfactory prediction accuracy regarding R-2 (0.9709), VAF (97.0911%), RMSE (3.4489), and MAE (2.6451), outperforming previously developed models.
Review
Green & Sustainable Science & Technology
Pooya Dastpak, Rita L. Sousa, Daniel Dias
Summary: Sinkholes are a major underground hazard that threatens infrastructure and lives, with significant costs and increased flood risk. Urban sinkholes are mainly manmade due to soil erosion from aging pipes. Climate change, storm surges, and urbanization contribute to increased subsidence in urban environments. Further experimental and numerical research is urgently needed to expand understanding of internal soil erosion due to defective pipes (SEDP).
Article
Chemistry, Multidisciplinary
Chuanqi Li, Daniel Dias
Summary: This paper utilizes four metaheuristic optimization algorithms to optimize the random forest model for predicting the rock elasticity modulus (EM), and evaluates the predictive performance of different models. The results show that the PRO-RF model achieves the best prediction accuracy, and porosity (Pn) is the most important variable for predicting the rock EM. This study provides a good example for the subsequent application of soft techniques in EM and other important rock parameter estimations.
APPLIED SCIENCES-BASEL
(2023)
Article
Engineering, Civil
Ngoc Anh Do, Van Vi Pham, Daniel Dias
Summary: This paper focuses on a new pseudo-static loading scheme for sub-rectangular tunnels using the Hyperstatic Reaction Method (HRM). New equations that allow for the computation of applied active loading and a variable spring stiffness coefficient are developed to depict the interaction between the soil and the tunnel lining. Through a numerical study considering various factors, the proposed loading scheme is calibrated and validated, demonstrating the effectiveness of the developed HRM method for the preliminary seismic design of sub-rectangular tunnels.
SUSTAINABLE AND RESILIENT INFRASTRUCTURE
(2023)
Article
Construction & Building Technology
Dianchun Du, Di Lei, Keqi Liu, Daniel Dias
Summary: This study investigates the lining internal forces of a quasi-rectangular tunnel designed according to the Hoek-Brown criterion in rock masses. By transforming the strength parameters and using the Hyperstatic Reaction Method (HRM), the influence of different tunnel depths, rock strengths, and geological parameters on the lining internal forces is analyzed. The results show that these parameters have a significant effect on the lining internal forces of the quasi-rectangular tunnel.
Article
Construction & Building Technology
Zhi Ding, Xiao Zhang, Shao-Heng He, Yong-Jie Qi, Cun-Gang Lin
Summary: This study investigates the longitudinal behavior of a shield tunnel by designing and constructing a reduced-size indoor model. The results show that the longitudinal settlement of the tunnel follows a normal distribution, with the maximum settlement occurring at the central ring and increasing linearly with the applied load. Stress concentration typically occurs on the side of the tunnel waist under surcharge, resulting in transverse elliptical deformation of the entire structure.
TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY
(2024)
Article
Construction & Building Technology
Lucia Lopez-de-Abajo, Marcos G. Alberti, Jaime C. Galvez
Summary: Assessing and predicting concrete damage is crucial for infrastructure management. This study quantifies gas concentrations in urban tunnels to achieve this goal.
TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY
(2024)
Article
Construction & Building Technology
Chao He, Yinghao Cai, Chenqiang Pu, Shunhua Zhou, Honggui Di, Xiaohui Zhang
Summary: This paper investigates the impact of river channel excavation on adjacent metro tunnels and proposes protective measures based on an engineering project in Fuzhou, China. A three-dimensional finite element model is developed to calculate the displacements and distortion of tunnels under different excavation sequences and soil reinforcement measures. Real-time monitoring confirms that the vertical displacements and diametrical distortion of tunnels are primarily caused by the excavation of the river above the tunnels, while horizontal displacements are induced by the excavation next to the tunnels. The study recommends a combination of cement slurry with a portal form and concrete with a plate form for soil reinforcement and tunnel protection.
TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY
(2024)
Article
Construction & Building Technology
Yaosheng Liu, Ang Li, Feng Dai, Ruochen Jiang, Yi Liu, Rui Chen
Summary: In this study, a hybrid model based on a multilayer perceptron (MLP) and meta-heuristic algorithms was developed to improve blast performance during tunnel excavation. Precise prediction of post-blasting indicators was important for optimization, and a comparison of meta-heuristic algorithms was conducted to find the most suitable model. The results showed that the developed model effectively reduces overbreak areas and quantitatively analyzes the influence of geological conditions.
TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY
(2024)
Article
Construction & Building Technology
Xiang Shen, Yifan Chen, Liqiang Cao, Xiangsheng Chen, Yanbin Fu, Chengyu Hong
Summary: In this paper, a machine learning-based method for predicting the slurry pressure in shield tunnel construction is proposed. By considering the influence of fault fracture zones and setting the formation influence coefficient, the accuracy of the prediction is significantly improved.
TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY
(2024)
Article
Construction & Building Technology
Shuying Wang, Zihao Zhou, Xiangcou Zheng, Jiazheng Zhong, Tengyue Zheng, Changhao Qi
Summary: A real-time assessment and monitoring approach based on laser scanning technology and point cloud data analysis was proposed to address the hysteresis in assessing the workability of conditioned soils and the inefficiency in estimating the soil volume flow rate in tunnelling practice. The approach was successfully applied in identifying the workability of conditioned soil and its discharge rate in the EPB shield tunnelling project.
TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY
(2024)
Article
Construction & Building Technology
Peng Jiang, Benchao Liu, Yuting Tang, Zhengyu Liu, Yonghao Pang
Summary: This study introduces a novel deep learning-based electrical method that jointly inverses resistivity and chargeability to estimate water-bearing structures and water volume. Compared with traditional linear inversion methods, the proposed method demonstrates superiority in locating and delineating anomalous bodies, reducing solution multiplicity.
TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY
(2024)
Article
Construction & Building Technology
Haoyu Mao, Nuwen Xu, Zhong Zhou, Chun Sha, Peiwei Xiao, Biao Li
Summary: The study focuses on the delineation of rock mass damage zones and stability analysis of underground powerhouse in Lianghekou hydropower station. ESG monitoring system is used to monitor the inner micro-fracture activity of surrounding rock mass in real-time. Engineering analogy method is adopted to forecast the deformation period of surrounding rock mass and analyze the variation characteristics of seismic source parameters. The research results provide references for similar deep underground excavation engineering in terms of design and construction.
TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY
(2024)
Article
Construction & Building Technology
Junling Qiu, Dedi Liu, Kai Zhao, Jinxing Lai, Xiuling Wang, Zhichao Wang, Tong Liu
Summary: This study focuses on the construction surface cracks of large cross-section tunnels in loess strata of China. The mechanism of surface crack formation is analyzed, and factors such as settlement deformation, construction scheme, and surrounding soil environment are identified as the main contributors. Numerical simulations were conducted to gain a deeper understanding of the influence of factors on surface cracks in loess tunnel construction. Specific measures for prevention and treatment of construction surface cracks are proposed to provide new ideas for surface crack control in loess tunnels.
TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY
(2024)
Article
Construction & Building Technology
Ting Shang, Jiaxin Lu, Ying Luo, Song Wang, Zhengyu He, Aobo Wang
Summary: The study reveals significant variations in car-following behavior across different types of tunnels and consecutive sections of the same tunnel. As tunnel length increases, the driving stability of following vehicles decreases, but the level of driving safety risk is not positively correlated with tunnel length. Significant vehicle trajectory oscillation is observed within the inner sections of long and extra-long tunnels, and a significant relationship between the acceleration of following vehicles and the location within the tunnel section is found.
TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY
(2024)
Article
Construction & Building Technology
Rusi Zeng, Zhongwei Shen, Jun Luo
Summary: The urban underground complexes (UUCs) in China have been effective in solving urban problems, but users have expressed dissatisfaction with the internal physical environment. Personal characteristics and environmental factors play significant roles in determining users' satisfaction.
TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY
(2024)
Article
Construction & Building Technology
Gabriel Lehmann, Heiko Kaeling, Sebastian Hoch, Kurosch Thuro
Summary: Analysing and predicting the advance rate of a tunnel boring machine (TBM) in hard rock is important for tunnelling projects. This study focuses on small-diameter TBMs and their unique characteristics, such as insufficient geotechnical information and special machine designs. A database of 37 projects with 70 geotechnically homogeneous areas is compiled to investigate the performance of small-diameter TBMs. The analysis shows that segment lining TBMs have higher penetration rates, and new approaches for the penetration prediction of pipe jacking machines in hard rock are proposed.
TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY
(2024)
Article
Construction & Building Technology
Ting Ren, Ming Qiao, Jon Roberts, Jennifer Hines, Yang-Wai Chow, Wei Zong, Adrian Sugden, Mark Shepherd, Matthew Farrelly, Gareth Kennedy, Faisal Hai, Willy Susilo
Summary: Long-term exposure to coal and silica dust during underground tunnelling operations is a growing concern. To bridge the gap between knowledge in dust exposure monitoring and frontline workers, a virtual reality educational tool was developed to visualize ventilation and dust flow characteristics. This tool allows workers to better understand decision-making and best practices for dust controls.
TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY
(2024)
Article
Construction & Building Technology
Dong Lin, Zhipeng Zhou, Miaocheng Weng, Wout Broere, Jianqiang Cui
Summary: Metro systems play a vital role in the transportation, economic, environmental and social aspects of cities. The uncertainties in construction, passenger comfort and safety, as well as efficiency and reliability of the metro system, have been widely studied. Metro systems influence urban development and have a positive impact on housing prices, public health, and environmental quality. Further research is needed to fill the research gaps and make recommendations for future studies.
TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY
(2024)
Article
Construction & Building Technology
Wei Yu, Bo Wang, Xin Zi, Jie Dong
Summary: In this study, a whole-process analytical theory for the coupled deformation of deep circular tunnel surrounding rock and prestressed yielding anchor bolt (cable) system is derived and validated through numerical simulations. The results show that anchor bolts (cables) can significantly reduce the convergence of surrounding rock, and factors such as support timing and anchor cable length have important effects on the support effectiveness.
TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY
(2024)
