Tunnelling and Underground Space Technology最新文献_第2页

A novel multi-scale hybrid connected neural network for anti-noise rock fragmentation classification of tunnel boring machine

IF 6.7 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2025-03-13 DOI: 10.1016/j.tust.2025.106555

Guoqiang Huang, Chengjin Qin, Tao Zhong, Chengliang Liu

The surrounding rock condition of tunneling palm face can be obtained by recognizing the degree of rock fragmentation on the tunnel boring machine (TBM) conveyor belt. However, prolonged exposure to water mist and dust significantly degrades the image quality of rock fragmentation, which poses a significant challenge to achieving accurate image recognition. This paper proposes a multi-scale hybrid connected neural network (MHCNN) for anti-noise rock fragmentation classification in TBM construction. The proposed method designs two neural network branches to extract multi-dimensional features from rock fragmentation images and share features locally, and constructs multiple residual and dense connection blocks to capture the edge features of rock fragmentation. Moreover, a feature transfer bridge based on the feature transfer block is designed, which can adjust the feature dimensions as well as the weights, for sharing the features extracted from the special nodes of the two branches. Finally, the dataset taken at the site of Baolin Tunnel is used to verify the robustness and superiority of the method, and fully compare with the state-of-the-art algorithms. The experimental results show that the recall of MHCNN is 93.11% in the noiseless dataset, which is 5.19%-51.15% higher compared to other methods. The recall is 5.68%-58.93%, 14.86%-55.56%, and 26.61%-44.7% higher in light, medium, and heavy water-mist covered datasets, respectively. The recall of the proposed method increases by 2.88%-45.85%, 12.2%-41.99%, and 19.49%-44% for light, moderate, and heavy dust obscuration, respectively, which confirms the strong robustness and value of the method for practical engineering applications.

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引用次数: 0

Soil disturbance induced by urban shield tunnelling in sandy pebble soil considering non-coaxiality and anisotropy

IF 6.7 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2025-03-13 DOI: 10.1016/j.tust.2025.106573

Jian Cui , Zhigang Yao , Tao Yu , Kaichen Ying , Yong Fang , Wanghao Xu , Yufang Zhang , Jian Li , Bo Liu

Shield tunnelling through densely populated urban areas inevitably disturbs the surrounding soil, potentially posing significant safety risks to nearby buildings and structures. The constitutive models currently employed in numerical simulations for tunnel engineering are predominantly confined to the assumptions of isotropy and coaxiality, making it challenging to adequately capture the complexity of the mechanical response of the soil surrounding the tunnel. Based on the proposed non-coaxial and anisotropic elastoplastic Mohr-Coulomb yield criterion, this study carries out numerical simulation analyses of soil disturbance induced by urban shield tunnelling. Herein, the anisotropic parameters n and β jointly determine the shape of the anisotropic yield surface. The results demonstrate that rotation of the principal stress axes is observed in most areas of the soil surrounding the tunnel face, with the phenomenon being particularly pronounced at the crown and the invert of the tunnel. As the anisotropic parameter n decreases, the maximum surface settlement above the tunnel axis increases. The influence of anisotropy on higher-stress unloading coefficients is significant, resulting in the development of a wider plastic zone around the tunnel. As the coefficient of lateral earth pressure at rest K₀ increases, the maximum surface settlement gradually reduces. Under the influence of anisotropic parameter β or non-coaxial parameter k, the maximum surface settlement exhibits an approximately linear relationship with K₀. However, the anisotropic parameter n has a significant influence on the trend of the maximum surface settlement with respect to K₀, which leads to a non-linear relationship. Neglecting the effects of soil anisotropy, non-coaxiality, and the coefficient of lateral earth pressure at rest may lead to design schemes that are potentially unsafe. The results of this research can provide engineers with design bases for construction parameters and soil disturbance control while shield tunnelling in sandy pebble soil.

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引用次数: 0

Experimental study of the pore pressure variation during EPB shield tunnelling in the saturated sand

IF 6.7 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2025-03-13 DOI: 10.1016/j.tust.2025.106576

Jingmin Xu, Xiaoyu Wu, He Huang, Yifei Mao

During tunnelling with an earth pressure balance (EPB) shield in the sandy soil, the support pressure at the tunnel face depends on the properties of the muck (soil-foam mixture). Five series of foam infiltration tests were performed to investigate the effects of foam expansion ratio (FER), foam injection ratio (FIR), initial pressure gradient at the tunnel face, air pressure in the excavation chamber and the types of soil on the pressure variation in the soil in front of the tunnel face. The sand used to make the muck and sand column is the same. The experimental results show that both higher FER and FIR values lead to faster pore pressure drop. A minimum initial pressure is required to drive the foam further infiltrate into the soil. Moreover, a higher initial pressure gradient over the sand column leads to a faster pore pressure drop. For foam flow from the muck into the saturated sand, the model of foam infiltration can well describe the soil with a relatively high permeability, whereas overestimates the pore pressure but underestimates the water discharge volumes for the soil with a relatively low permeability.

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引用次数: 0

Influence of sidewall restriction on ceiling temperature distribution induced by double fires in a channel: Experimental and numerical investigations

IF 6.7 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2025-03-13 DOI: 10.1016/j.tust.2025.106553

Shengzhong Zhao , Kai Du , Yongzheng Yao , Tiantian Xu , Fei Wang , Lin Xu , Wenjun Lei

In this paper, the influence of sidewall restriction on the temperature distribution beneath the channel ceiling induced by double fires was experimentally and numerically investigated. Two fire scenarios (center and wall fires) were defined and analyzed. Heat release rate (HRR) and fire separation distance (S) were taken as the primary analysis variables. The results show that with the increase in fire separation distance, the temperature distribution beneath the channel ceiling transitions from a “single-hump” shape to an “M” shape, and the “M” shape temperature distribution appears relatively late for the wall fires. The maximum temperature rise beneath the channel ceiling decreases with increasing S/D, and it is larger under the same HRR and S/D for the wall fires. The temperature decay coefficient K decreases with S/D and increases with HRR, and the temperature decay rate of the wall fire is greater than that of the center fire. Finally, prediction models of the maximum temperature rise and longitudinal temperature decay are proposed for the center and wall fires, respectively. This study is anticipated to contribute novel insights to the design of ceiling fire-resistant materials and fire smoke control in channel-like spaces.

{"title":"Influence of sidewall restriction on ceiling temperature distribution induced by double fires in a channel: Experimental and numerical investigations","authors":"Shengzhong Zhao , Kai Du , Yongzheng Yao , Tiantian Xu , Fei Wang , Lin Xu , Wenjun Lei","doi":"10.1016/j.tust.2025.106553","DOIUrl":"10.1016/j.tust.2025.106553","url":null,"abstract":"<div><div>In this paper, the influence of sidewall restriction on the temperature distribution beneath the channel ceiling induced by double fires was experimentally and numerically investigated. Two fire scenarios (center and wall fires) were defined and analyzed. Heat release rate (HRR) and fire separation distance (<em>S</em>) were taken as the primary analysis variables. The results show that with the increase in fire separation distance, the temperature distribution beneath the channel ceiling transitions from a “single-hump” shape to an “M” shape, and the “M” shape temperature distribution appears relatively late for the wall fires. The maximum temperature rise beneath the channel ceiling decreases with increasing <em>S/D</em>, and it is larger under the same HRR and <em>S/D</em> for the wall fires. The temperature decay coefficient <em>K</em> decreases with <em>S/D</em> and increases with HRR, and the temperature decay rate of the wall fire is greater than that of the center fire. Finally, prediction models of the maximum temperature rise and longitudinal temperature decay are proposed for the center and wall fires, respectively. This study is anticipated to contribute novel insights to the design of ceiling fire-resistant materials and fire smoke control in channel-like spaces.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"161 ","pages":"Article 106553"},"PeriodicalIF":6.7,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143611374","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}

引用次数: 0

Flexural behaviour of longitudinal segment joints with quick C–T type connectors and their corrosion characteristics

IF 6.7 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2025-03-13 DOI: 10.1016/j.tust.2025.106542

Yudong Wu , Wenqi Ding , Qing Chen , Yafei Qiao

To address the challenges of slow construction and low assembly precision associated with traditional bolted joints, a novel type of longitudinal joint connected by quick C–T type connectors (C–T joints) has emerged. While this new joint design offers improved flexural behaviour, the connectors are more sensitive to corrosion. Thus, this paper comprehensively investigated the mechanical properties of C–T joints, and the effects of corrosion were also highlighted. First, a series of full-scale experiments and fine numerical simulations are performed to elucidate the flexural behaviour and failure pattern of C–T joints. A numerical simulation method for corroded connectors is then proposed based on corrosion experiments with C/T connectors and is used to explore the corrosion effect on the mechanical properties of C–T joints. The flexural process of the C–T joint can be divided into four stages. The first three stages are the initial high-stiffness, free deformation after the axial force is balanced, and increased stiffness upon connector contact. During the regular tunnel operation stage, the joint remains in the initial two stages. The fourth stage behaves differently under positive and negative moments because of structural disparities between the intrados and extrados. Positive moments result in connector fracture, whereas the compression zone of concrete collapse occurs under negative moments. In both scenarios, cracks emerge and extend outwards from the connectors on the joint plane, meaning that the anchoring of C–T connectors is a key design point. Corrosion has little influence on the mechanical properties of joints before the connectors contact, but it prolongs the second stage, shortens the third stage, and causes a rapid decrease in the ultimate bearing capacity of the joint. When corrosion is more severe, the bearing capacity of the joint remains consistently low.

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引用次数: 0

Study on the damage mechanism of water and mud inrush in a tunnel with water-rich fault zones based on experiment and numerical modeling

IF 6.7 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2025-03-12 DOI: 10.1016/j.tust.2025.106575

Jiale Xie, Peijie Yin, Xiaohua Yang, Changgen Yan, Huaixin Li, Duo Yan, Hongzhe Fu

Tunnel construction has become increasingly challenging in water-rich fault fracture zones, and failure evolution of tunnel traversing is essential for understanding the deformation characteristics. In this study, the dynamic evolution of water and mud inrush in tunnels crossing water-rich fault zones was investigated by the experimental test and numerical simulation based on Discrete Element Method (DEM) and Finite Difference Method (FDM). According to the experimental results, two abrupt points in water inflow can be observed in model tests, with inflow volumes of 0.102 m³/h and 0.318 m³/h. The water pressure variation at the tunnel haunch is 2.87 % and 20.15 %, and the tunnel crown is 5.85 % and 17.50 %, respectively. The safety thickness of the burst-prevention layer is about 5 cm in the experiment. The water inrush and water pressure are compared for both the experiment and numerical simulation and a good agreement has been obtained. The numerical results show that the fault near the tunnel face has an explosive potential, while areas farther away experience delays in destruction. The time required to form a new settlement trough within the fault progressively increases, and the curvature of the fault slip surface grows over time. The fault area is influenced in three directions, with the vertical direction being the most affected, measuring 1.2 to 1.5 times the horizontal direction. Damage in the horizontal direction significantly diminishes when the affected area extends to 2.36 times the tunnel diameter. The findings could provide valuable guidance for preventing water and mud inrush risks during tunnel construction.

{"title":"Study on the damage mechanism of water and mud inrush in a tunnel with water-rich fault zones based on experiment and numerical modeling","authors":"Jiale Xie, Peijie Yin, Xiaohua Yang, Changgen Yan, Huaixin Li, Duo Yan, Hongzhe Fu","doi":"10.1016/j.tust.2025.106575","DOIUrl":"10.1016/j.tust.2025.106575","url":null,"abstract":"<div><div>Tunnel construction has become increasingly challenging in water-rich fault fracture zones, and failure evolution of tunnel traversing is essential for understanding the deformation characteristics. In this study, the dynamic evolution of water and mud inrush in tunnels crossing water-rich fault zones was investigated by the experimental test and numerical simulation based on Discrete Element Method (DEM) and Finite Difference Method (FDM). According to the experimental results, two abrupt points in water inflow can be observed in model tests, with inflow volumes of 0.102 m<sup>3</sup>/h and 0.318 m<sup>3</sup>/h. The water pressure variation at the tunnel haunch is 2.87 % and 20.15 %, and the tunnel crown is 5.85 % and 17.50 %, respectively. The safety thickness of the burst-prevention layer is about 5 cm in the experiment. The water inrush and water pressure are compared for both the experiment and numerical simulation and a good agreement has been obtained. The numerical results show that the fault near the tunnel face has an explosive potential, while areas farther away experience delays in destruction. The time required to form a new settlement trough within the fault progressively increases, and the curvature of the fault slip surface grows over time. The fault area is influenced in three directions, with the vertical direction being the most affected, measuring 1.2 to 1.5 times the horizontal direction. Damage in the horizontal direction significantly diminishes when the affected area extends to 2.36 times the tunnel diameter. The findings could provide valuable guidance for preventing water and mud inrush risks during tunnel construction.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"161 ","pages":"Article 106575"},"PeriodicalIF":6.7,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143610755","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}

引用次数: 0

Study on the effect of high-temperature combustion on damage evolution and mechanical properties of rock-like materials

IF 6.7 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2025-03-12 DOI: 10.1016/j.tust.2025.106556

Yubai Li , Siyuan He , Yue Zhai , Junnan Zhao , Yaoying Huang

In addressing the frontier issue of high-temperature damage mechanisms in underground engineering fires and their impact on lining concrete and surrounding rock mechanical properties, this study focuses on C35 concrete as the primary subject of investigation, with granite from tunnel sections in the Sichuan-Tibet region serving as a reference. The research analyzes the evolution of damage and mechanical responses of rock-like materials after exposure to high-temperature fire. The findings indicate that under high-temperature conditions, granite and concrete experience increased cross-sectional porosity due to factors such as cementitious material failure, mineral expansion, and decomposition. This porosity exhibits temporal and spatial characteristics, increasing logarithmically with exposure time and decreasing linearly with specimen height from the heated surface. As the high-temperature test time increases, the peak stress of granite and concrete specimens gradually decreases, and the rate of decrease gradually increases.The maximum peak stress reduction rates of the three strain rates were 80.49 %, 82.68 % and 59.42 % for granite specimens, and 47.48 %, 51.68 % and 50.98 % for concrete specimens. The compressive strength shows a negative correlation with exposure time, accompanied by a transition from brittle to ductile failure characteristics. These research conclusions hold significant theoretical importance for understanding the evolution of damage and changes in mechanical properties of surrounding rock and lining concrete after high-temperature fires in underground engineering, providing fundamental data for post-fire safety assessments.

{"title":"Study on the effect of high-temperature combustion on damage evolution and mechanical properties of rock-like materials","authors":"Yubai Li , Siyuan He , Yue Zhai , Junnan Zhao , Yaoying Huang","doi":"10.1016/j.tust.2025.106556","DOIUrl":"10.1016/j.tust.2025.106556","url":null,"abstract":"<div><div>In addressing the frontier issue of high-temperature damage mechanisms in underground engineering fires and their impact on lining concrete and surrounding rock mechanical properties, this study focuses on C35 concrete as the primary subject of investigation, with granite from tunnel sections in the Sichuan-Tibet region serving as a reference. The research analyzes the evolution of damage and mechanical responses of rock-like materials after exposure to high-temperature fire. The findings indicate that under high-temperature conditions, granite and concrete experience increased cross-sectional porosity due to factors such as cementitious material failure, mineral expansion, and decomposition. This porosity exhibits temporal and spatial characteristics, increasing logarithmically with exposure time and decreasing linearly with specimen height from the heated surface. As the high-temperature test time increases, the peak stress of granite and concrete specimens gradually decreases, and the rate of decrease gradually increases.The maximum peak stress reduction rates of the three strain rates were 80.49 %, 82.68 % and 59.42 % for granite specimens, and 47.48 %, 51.68 % and 50.98 % for concrete specimens. The compressive strength shows a negative correlation with exposure time, accompanied by a transition from brittle to ductile failure characteristics. These research conclusions hold significant theoretical importance for understanding the evolution of damage and changes in mechanical properties of surrounding rock and lining concrete after high-temperature fires in underground engineering, providing fundamental data for post-fire safety assessments.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"161 ","pages":"Article 106556"},"PeriodicalIF":6.7,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143600954","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}

引用次数: 0

Effective curing of waste mud from slurry shield tunnels using OPC-MCA: Experimental investigations and microstructural analysis

IF 6.7 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2025-03-10 DOI: 10.1016/j.tust.2025.106554

Henggen Zhang , Tao Liu , Weihua Wang , Yuxue Cui , Yankun Wu , Xinyi Qiu

To address the problems of large volume, complex composition, difficulty in treatment and environmental pollution of the waste mud (WM) generated in urban slurry shield tunnels, the ground granulated blast-furnace slag (GGBS), calcium aluminate powder (CAP), fuel gas desulfurization gypsum (FGDG), lime and alunite were incorporated into ordinary Portland cement (OPC) to develop a new modified curing agent (OPC-MCA). The optimal addition ratio of various admixtures in OPC-MCA was determined through orthogonal tests. The mechanical properties of the two different types of WM (i.e., Wuhu and Wuhan WM) after curing with 10–40% OPC and OPC-MCA were investigated by laboratory tests. The microstructure, pore and crack evolution characteristics as well as mineral composition changes of the cured WM specimens were analyzed using the scanning electron microscope (SEM), X-ray computed tomography (CT) and X-ray diffraction (XRD). The curing performance and microscopic action mechanism of the two curing agents on shield tunnel WM were investigated. The results confirmed that the optimum ratio of OPC-MCA was 51% OPC, 32% GGBS, 8% FGDG, 5% CAP, 3% lime and 1% alunite. OPC-MCA exhibited better curing performance than OPC, especially at low dosages, and the curing effect of OPC-MCA for Wuhu WM was better than that for Wuhan WM. The cured WM specimens mostly presented shear failure, but with the increase of curing age and curing agent dosage, some specimens underwent tensile failure with increased strength and brittleness. Calcium aluminium silicate hydrate (C-A-S-H) and monosulfate (AFm) were detected in the OPC-MCA cured WM specimens, while these hydration products were not detected in the OPC cured WM specimens, and the higher content of ettringite (AFt) was also observed in the OPC-MCA cured WM specimens. The proportion of large pores and the total pore volume of the OPC-MCA cured WM specimens were smaller than those of the OPC cured WM specimens at same curing agent dosage.

{"title":"Effective curing of waste mud from slurry shield tunnels using OPC-MCA: Experimental investigations and microstructural analysis","authors":"Henggen Zhang , Tao Liu , Weihua Wang , Yuxue Cui , Yankun Wu , Xinyi Qiu","doi":"10.1016/j.tust.2025.106554","DOIUrl":"10.1016/j.tust.2025.106554","url":null,"abstract":"<div><div>To address the problems of large volume, complex composition, difficulty in treatment and environmental pollution of the waste mud (WM) generated in urban slurry shield tunnels, the ground granulated blast-furnace slag (GGBS), calcium aluminate powder (CAP), fuel gas desulfurization gypsum (FGDG), lime and alunite were incorporated into ordinary Portland cement (OPC) to develop a new modified curing agent (OPC-MCA). The optimal addition ratio of various admixtures in OPC-MCA was determined through orthogonal tests. The mechanical properties of the two different types of WM (i.e., Wuhu and Wuhan WM) after curing with 10–40% OPC and OPC-MCA were investigated by laboratory tests. The microstructure, pore and crack evolution characteristics as well as mineral composition changes of the cured WM specimens were analyzed using the scanning electron microscope (SEM), X-ray computed tomography (CT) and X-ray diffraction (XRD). The curing performance and microscopic action mechanism of the two curing agents on shield tunnel WM were investigated. The results confirmed that the optimum ratio of OPC-MCA was 51% OPC, 32% GGBS, 8% FGDG, 5% CAP, 3% lime and 1% alunite. OPC-MCA exhibited better curing performance than OPC, especially at low dosages, and the curing effect of OPC-MCA for Wuhu WM was better than that for Wuhan WM. The cured WM specimens mostly presented shear failure, but with the increase of curing age and curing agent dosage, some specimens underwent tensile failure with increased strength and brittleness. Calcium aluminium silicate hydrate (C-A-S-H) and monosulfate (AFm) were detected in the OPC-MCA cured WM specimens, while these hydration products were not detected in the OPC cured WM specimens, and the higher content of ettringite (AFt) was also observed in the OPC-MCA cured WM specimens. The proportion of large pores and the total pore volume of the OPC-MCA cured WM specimens were smaller than those of the OPC cured WM specimens at same curing agent dosage.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"161 ","pages":"Article 106554"},"PeriodicalIF":6.7,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143592417","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}

引用次数: 0

Reliability analysis of underground water-sealed storage caverns stability: Method and application

IF 6.7 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2025-03-09 DOI: 10.1016/j.tust.2025.106550

Wei Li , Chenghua Hong , Liping Qiao , Jingyi Ma , Zhenhua Peng , Zhechao Wang

The reliability analysis method considers the uncertainty of rock parameters, making the stability analysis of underground engineering more accurate. A reliability analysis method applicable to assess the stability of underground water-sealed storage caverns was proposed in the study. In the method, the performance functions were established from the perspectives of the plastic zone and cavern displacement by modifying the elastic–plastic solution of the circular tunnel. The reliability index and probability of failure were calculated using the first-order reliability method and the reliability analysis results calculated by the proposed method and the Monte Carlo method was used to verify the correctness of the proposed method. Finally, the reliability analysis method was used to evaluate the reliability of an underground water-sealed storage caverns stability in southern China. The reliability index and probability of failure of the storage caverns with different support ways were obtained and the optimization design of the support system was determined based on the reliability analysis results.

{"title":"Reliability analysis of underground water-sealed storage caverns stability: Method and application","authors":"Wei Li , Chenghua Hong , Liping Qiao , Jingyi Ma , Zhenhua Peng , Zhechao Wang","doi":"10.1016/j.tust.2025.106550","DOIUrl":"10.1016/j.tust.2025.106550","url":null,"abstract":"<div><div>The reliability analysis method considers the uncertainty of rock parameters, making the stability analysis of underground engineering more accurate. A reliability analysis method applicable to assess the stability of underground water-sealed storage caverns was proposed in the study. In the method, the performance functions were established from the perspectives of the plastic zone and cavern displacement by modifying the elastic–plastic solution of the circular tunnel. The reliability index and probability of failure were calculated using the first-order reliability method and the reliability analysis results calculated by the proposed method and the Monte Carlo method was used to verify the correctness of the proposed method. Finally, the reliability analysis method was used to evaluate the reliability of an underground water-sealed storage caverns stability in southern China. The reliability index and probability of failure of the storage caverns with different support ways were obtained and the optimization design of the support system was determined based on the reliability analysis results.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"161 ","pages":"Article 106550"},"PeriodicalIF":6.7,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143580228","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}

引用次数: 0

A novel analytical method for describing ground motion behaviour caused by tunnel excavation

IF 6.7 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2025-03-09 DOI: 10.1016/j.tust.2025.106546

Qingtao Lin, Tao Song, Dechun Lu, Xiuli Du

A model is proposed to describe the soil movement caused by tunnel excavation. The mathematical relationships for soil displacement in both the horizontal and vertical directions are established. An optimized Gaussian function is developed to accommodate various ground conditions for describing vertical displacement, then, a formula for horizontal displacement is derived on this basis, providing a unified calculation method for both vertical and horizontal displacements. Utilizing the principles of elastic–plastic mechanics, the vertical and horizontal strains of soil are obtained by solving the first-order partial derivative of the displacement formulas. Subsequently, formulas for volume strain and engineering shear strain are derived using the Mohr strain circle. The validity of the displacement and strain formulas is confirmed through comparison with measured results from sandy strata (4 sets) and clay strata (2 sets). In conclusion, a comprehensive empirical framework for analyzing ground disturbance caused by tunnel excavation is established. The method relies on just two parameters and four known quantities, making it convenient for practical engineering.

{"title":"A novel analytical method for describing ground motion behaviour caused by tunnel excavation","authors":"Qingtao Lin, Tao Song, Dechun Lu, Xiuli Du","doi":"10.1016/j.tust.2025.106546","DOIUrl":"10.1016/j.tust.2025.106546","url":null,"abstract":"<div><div>A model is proposed to describe the soil movement caused by tunnel excavation. The mathematical relationships for soil displacement in both the horizontal and vertical directions are established. An optimized Gaussian function is developed to accommodate various ground conditions for describing vertical displacement, then, a formula for horizontal displacement is derived on this basis, providing a unified calculation method for both vertical and horizontal displacements. Utilizing the principles of elastic–plastic mechanics, the vertical and horizontal strains of soil are obtained by solving the first-order partial derivative of the displacement formulas. Subsequently, formulas for volume strain and engineering shear strain are derived using the Mohr strain circle. The validity of the displacement and strain formulas is confirmed through comparison with measured results from sandy strata (4 sets) and clay strata (2 sets). In conclusion, a comprehensive empirical framework for analyzing ground disturbance caused by tunnel excavation is established. The method relies on just two parameters and four known quantities, making it convenient for practical engineering.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":"161 ","pages":"Article 106546"},"PeriodicalIF":6.7,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143580225","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}

引用次数: 0