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The jointing stress analysis of one-shot seal-off high-voltage vacuum interrupters 认领 引用
1
作者 赵智忠 邹积岩 +2 位作者 丛吉远 文化宾 孙辉 《China Welding》 EI CAS 2006年第2期50-54,共5页
The free shrinkage of ceramic or metal is restricted due to solidification of the solder. Hence the shrinkage stress arises and the jointing strength is reduced during the brazing of high-voltage vacuum interrupters ... The free shrinkage of ceramic or metal is restricted due to solidification of the solder. Hence the shrinkage stress arises and the jointing strength is reduced during the brazing of high-voltage vacuum interrupters （HVVIs）. The solder bound contour was gained by solved energy bound equation. The finite element model of weld beads was established with Surface Evolver software. Then the stress in two different cooling techniques （ natural cooling and force cooling） was calculated with ANSYS. Comparing the stress, a better cooling technique was selected for HVVIs. Its cooling time is shortened by 3 hours while the jointing stress doesn＇ t increase and the tensile strength of ceramic to metal seal is not decreased. The stress-rupture tests have validated the calculated results. More important, a method is found, by which the brazing technique could be improved in advance instead of blind experiments. 展开更多
关键词 high-voltage vacuum interrupters brazing cooling technique finite element jointing stress
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A Bio-inspired Interlocking Structure to Enhance Metal-Polymer Joint Strength by Additive Manufacturing and Injection Molding Processes 认领 引用
2
作者 Heng Zhang Zeyan Li Xiaohong Ding 《Journal of Bionic Engineering》 SCIE EI CSCD 2026年第3期1662-1679,共18页
The connection between metal and polymer is crucial for lightweight manufacturing in the electronics,automotive,aerospace industries and so on.Inspired by biological curves,this study proposes a novel biomimetic inter... The connection between metal and polymer is crucial for lightweight manufacturing in the electronics,automotive,aerospace industries and so on.Inspired by biological curves,this study proposes a novel biomimetic interlocking structure,designed specifically to enhance the metal-polymer joint strength.Through this approach,superior connection strength is achieved compared to conventional structures.Three different interlocking structures—Dragonfly Head-Neck interlocking structure,Kelvin interlocking structure,and the propopsed Curved Body-Centered Cubic Lattice interlocking structure—were additively manufactured with stainless steel,followed by injection molding to form the metal-polymer connection structures.The bonding performance of these structures was evaluated through finite element analysis and experiment.The results indicate that the Curved Body-Centered Cubic lattice interlocking structure with a 10%fill rate exhibited the highest bonding strength,outperforming both the Kelvin interlocking structure and the Dragonfly Head-Neck interlocking structure.Reducing the stiffness of the metal subatrate near the metal-polymer connection rigon can establish efficient load transfer path,which leads to a uniform stress distribution within the polymer,and allows the polymer to better withstand tensile forces during loading,finally achieve the goal of enhance the bonding strength of of the metal-polymer jointing.This research offers an innovative approach to enhancing mechanical connection interface strength,with significant implications for improving the durability and performance of metal-polymer composites. 展开更多
关键词 Additive manufacturing Biomimetic interlocking structure Metal-polymer jointing Injection molding Connection strength
Digital twin driven ram BOP shear capability analysis 认领 引用 被引量：1
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作者 Feng-Li Zhang Jie Liu +1 位作者 Jin-Tao Ni Jin-Jiang Wang 《Petroleum Science》 SCIE EI CAS CSCD 2026年第6期3667-3681,共15页
As a critical component of the oil drilling control system,blowout preventers(BOPs)shear failure accidents can occur in case of blowout incidents.Existing methods based on simulation and empirical formula do not perfo... As a critical component of the oil drilling control system,blowout preventers(BOPs)shear failure accidents can occur in case of blowout incidents.Existing methods based on simulation and empirical formula do not perform well in systematically evaluating the shear capacity of ram BOPs,and relevant research and testing are conducted under static ideal conditions,leading to a lack of effective guidance in field operations.Aiming at the above problems,this paper proposes a shear capability evaluation method of ram BOPs based on digital twin.The shear mechanism of ram BOPs is analyzed and the digital twin model of a ram BOP driven by real-time drilling data is constructed through joint simulation and model reduction.Finally,the shear capacity of ram BOP is evaluated multi-dimensionally in real-time by using the built digital twin model.The model can also simulate shearing process offline under different preset conditions.The results provide a theoretical basis for field operation and performance evaluations of the shear capability of ram BOPs. 展开更多
关键词 Ram blowout preventer Joint simulation Digital twin Performance evaluation
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Impact of joint distribution within hard rock mass on tunnel blasting profile:Numerical simulation and field measurement 认领 引用 被引量：1
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作者 Junxin Li Wei Wu +2 位作者 Bingyi Pan Baosheng Dong Hehua Zhu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2026年第5期3760-3778,共19页
In hard rock tunnel excavation,controlling the blasting profile to prevent overbreak and underbreak is critical for safety and cost-effectiveness.Discontinuities such as joints and faults significantly affect the mech... In hard rock tunnel excavation,controlling the blasting profile to prevent overbreak and underbreak is critical for safety and cost-effectiveness.Discontinuities such as joints and faults significantly affect the mechanical properties of the rock mass,and their distribution critically influences the blasting outcomes.This study explores the impact of joint distribution on the tunnel blasting profile through field measurements and numerical simulations.Real-time monitoring of the tunnel face was conducted using the digital twin method,capturing both rock discontinuities and blasting profiles.Field results revealed that overbreak tends to occur at joints outside contour boreholes,where the joints lead the blasting profile diverging from the borehole connection line.To quantify this effect,dynamic finite element simulations were conducted to assess the influence of borehole-joint distances(d=25 cm,50 cm,and 100 cm)and intersecting joint angles(α=60°,90°,and 120°)on blasting stress wave propagation and rock fracture development.The results demonstrated that joints within the hard rock mass guide and restrain the propagation of blasting stress wave,leading to the formation of a fracture zone induced by the reflected stress wave(the RSW fracture zone).The morphology of the RSW fracture zone closely matched the field blasting profile,validating the numerical simulation results.Furthermore,the borehole-joint distance and the intersecting joint angle were found to govern the extent and geometry of the RSW fracture zone.These findings provide valuable insights for optimizing blasting designs in jointed hard rock masses to control tunnel excavation profiles better. 展开更多
关键词 Joint distribution Drilling and blasting Overbreak Dynamic finite element method Digital twin
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Quantitative evaluation of shear wear on natural and fresh skarn joint surfaces based on acoustic emission and 3D laser scanning technology 认领 引用 被引量：1
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作者 Zhiqiang Hou Ruifu Yuan +1 位作者 Boyuan Liu Wei Sun 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2026年第6期4568-4587,共20页
Weathering substantially impacts the shear mechanical properties and surface morphology of rock joints.This study quantitatively compared shear behavior,shear strength parameters,acoustic emission(AE)characteristics,a... Weathering substantially impacts the shear mechanical properties and surface morphology of rock joints.This study quantitatively compared shear behavior,shear strength parameters,acoustic emission(AE)characteristics,and surface wear of fresh and slightly weathered skarn joints under different constant normal load(CNL)conditions.The results indicated that weathering markedly degraded shear properties:the peak shear strength of weathered joints was only about 40%of that of fresh joints,and dilatancy behavior was absent during shearing of weathered joints.In contrast,fresh joints exhibited pronounced dilatancy,although this effect diminished with increasing normal stress.The AE signal response mechanisms of the two joint types were distinct.Analysis using the AE-based AF–RA(average frequency–rise time/amplitude)crack classification method(signal classification ratio k=5)revealed that fresh joints showed a higher proportion of tensile cracks.In contrast,weathered joints exhibited a larger proportion of shear cracks.Frequency-band analysis revealed that fresh joints predominantly generated medium-to high-frequency signals,whereas weathered joints predominantly generated medium-to low-frequency signals.Quantitative three-dimensional(3D)laser-scanning analysis further demonstrated that the extent of surface wear was substantially greater on weathered joints than on fresh ones.Weathering-induced degradation of the mechanical and surface properties of rock joints has important implications for the support design in fractured rock masses and for the practical application of rock-mass classification systems such as the Q-system and the Rock Mass Rating(RMR). 展开更多
关键词 Rock joint Weathering Direct shear test Acoustic emission(AE) Surface wear
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Experimental study on the frost jacking characteristics of bamboo joint conical piles in seasonally frozen regions 认领 引用 被引量：1
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作者 YaoHui Zhang HaiHong Yang +1 位作者 TieCheng Sun Jiao Zhang 《Research in Cold and Arid Regions》 CAS CSCD 2026年第1期11-21,共11页
The variation in pile types can to some extent reduce frost jacking displacement of pile foundations in seasonal frost regions,yet further research is needed on the anti-jacking-up performance of different pile types ... The variation in pile types can to some extent reduce frost jacking displacement of pile foundations in seasonal frost regions,yet further research is needed on the anti-jacking-up performance of different pile types under freeze-thaw cycles.This study conducted freeze-thaw cycle model tests under open-system conditions based on the proposed design concept of bamboo joint conical piles,analyzing variations in test fill temperature,moisture content,surface displacement,and pile-top displacement.The main findings are:(1)Pile type variation significantly affects pile foundation frost jacking,with bamboo joint conical piles demonstrating superior anti-jacking-up performance compared to straight piles and inferior performance to 9°conical piles.Moreover,the anti-jacking-up performance of bamboo joint conical piles follows a pattern of initial enhancement followed by attenuation with increasing cone angle,where a 7°cone angle provides optimal anti-jacking-up performance.(2)The moisture content of the soil fill increases with the number of freeze-thaw cycles in an open system environment,with the rate of increase decreasing over time,while the initial frozen core volume within the fill material tends to increase during the thawing phase.(3)The mechanisms underlying the frost heave and settlement of the fill surface and the frost jacking displacement at the pile top were clarified.The frost heave and settlement of the fill surface result from volume changes in the frozen soil due to the water-ice phase transition and the compaction effect on unfrozen soil.The thermal melting evolution of the frozen core in the fill material is the key factor determining the cumulative displacement at the pile top.(4)Differences in the thermophysical properties between the pile foundation and the fill material induce the migration of free water toward the vicinity of the pile,where the higher moisture content of the fill material is detrimental to the mitigation of frost jacking damage to the pile foundation.These findings provide a foundation for further elucidation of the frost jacking mechanism of bamboo joint conical piles in seasonally frozen regions under freeze-thaw cycles. 展开更多
关键词 Freeze-thaw cycles Bamboo joint conical piles Frost jacking characteristics Model test Open system
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Research on Vehicle Joint Radar Communication Resource Optimization Method Based on GNN-DRL 认领 引用 被引量：1
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作者 Zeyu Chen Jian Sun +1 位作者 Zhengda Huan Ziyi Zhang 《Computers, Materials & Continua》 SCIE EI 2026年第2期1430-1446,共17页
To address the issues of poor adaptability in resource allocation and low multi-agent cooperation efficiency in Joint Radar and Communication(JRC)systems under dynamic environments,an intelligent optimization framewor... To address the issues of poor adaptability in resource allocation and low multi-agent cooperation efficiency in Joint Radar and Communication(JRC)systems under dynamic environments,an intelligent optimization framework integrating Deep Reinforcement Learning(DRL)and Graph Neural Network(GNN)is proposed.This framework models resource allocation as a Partially Observable Markov Game(POMG),designs a weighted reward function to balance radar and communication efficiencies,adopts the Multi-Agent Proximal Policy Optimization(MAPPO)framework,and integrates Graph Convolutional Networks(GCN)and Graph Sample and Aggregate(Graph-SAGE)to optimize information interaction.Simulations show that,compared with traditional methods and pure DRL methods,the proposed framework achieves improvements in performance metrics such as communication success rate,Average Age of Information(AoI),and policy convergence speed,effectively enabling resource management in complex environments.Moreover,the proposed GNN-DRL-based intelligent optimization framework obtains significantly better performance for resource management in multi-agent JRC systems than traditional methods and pure DRL methods. 展开更多
关键词 Graph neural network joint radar and communication resource allocation multi-agent collaboration
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Lower limb joint kinetics during level walking in patients two years after anterior cruciate ligament reconstruction 认领 引用 被引量：1
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作者 Yiqun Lu Feng Zhao +6 位作者 Shengzheng Kuai Si Zhang Yuanyuan Yu Hongshi Huang Xi Gong Yingfang Ao Shuang Ren 《Sports Medicine and Health Science》 CAS CSCD 2026年第4期431-439,共9页
Gait asymmetries after anterior cruciate ligament reconstruction(ACLR)may lead to radiographic knee osteoarthritis(OA)and secondary injury.This study aimed to investigate three-dimensional(3D)lower limb joint kinetics... Gait asymmetries after anterior cruciate ligament reconstruction(ACLR)may lead to radiographic knee osteoarthritis(OA)and secondary injury.This study aimed to investigate three-dimensional(3D)lower limb joint kinetics using a multi-body dynamic analysis method based on a subject-specific musculoskeletal model during level walking 2 years after ACLR.A total of 23 patients(2 females and 21 males)2 years after ACLR were selected and underwent gait testing.3D motion joint reaction forces and the internal moments of the hip,knee,and ankle joints for the stance phase of each gait cycle were calculated by a musculoskeletal multibody dynamics model.In the hip and ankle joints,the peak of the first anteroposterior forces on the affected side were significantly smaller compared to the non-affected side(both p=0.04).The abduction(peak2:p=0.01)and the internal rotation moment(peak1:p=0.02;peak2:p=0.01)of the affected knee were significantly smaller than the non-affected side,but both of them did not reach the Minimal clinically important difference.The external rotation moment of the affected ankle moments was greater than the affected side(p<0.01).Two years after ACLR,there was no clinically significant kinetic abnormality in the affected knee joint,the kinetics of the hip and ankle joint were still abnormal,which may lead to the development of OA and secondary injury.Gait retraining should be used to improve the kinetics of the hip,knee,and ankle after ACLR. 展开更多
关键词 Anterior cruciate ligament Anterior cruciate ligament reconstruction Three-dimensional lower limb joint kinetics
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Coupled FEM-DEM modeling of permeability evolution in rough fractured shale during shearing under varying confining pressures 认领 引用 被引量：2
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作者 Bin Li Qi Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2026年第3期1736-1754,共19页
The dynamic evolution of fracture permeability presents a critical scientific challenge in rock masses.Understanding the mechanisms of rock mass permeability evolution is vital for engineering project design and opera... The dynamic evolution of fracture permeability presents a critical scientific challenge in rock masses.Understanding the mechanisms of rock mass permeability evolution is vital for engineering project design and operations.By integrating the discrete element method(DEM)with the finite element method(FEM),a numerical simulation framework for shear seepage in rough fractured shale has been developed to investigate the dynamic mechanisms of permeability evolution under varying confining pressures and during the shearing process.Numerical simulations were conducted on rough fractured samples under effective confining pressures ranging from 5 MPa to 20 MPa to monitor the aperture and permeability evolution of the fracture.The results of the numerical simulation are consistent with the experimental observations,indicating that both the shearing process and confining pressure significantly influence permeability.Moreover,the magnitude of the confining pressure is a crucial factor influencing the trend in permeability changes.Under a confining pressure of 5 MPa,fracture permeability initially increases significantly but decreases post-shearing.In contrast,a continuous decrease in fracture permeability is observed when the confining pressure exceeds 10 MPa.The results of the shear numerical simulation indicate that the confining pressure restricts fracture dilation during shearing,promotes the generation of rock debris,and decreases both the permeability and transmissivity of the fracture.The wear results obtained from numerical simulations are consistent with the experimental patterns and correlate with the joint roughness coefficient(JRC).This study proposed an effective numerical simulation method to reveal the evolution mechanism of fracture flow capacity,taking into account the wear of the fracture surface in shear simulations and the initial stress state of the rock in seepage simulations.This research explains the permeability evolution mechanism of fractured shale from a microscopic perspective,and the proposed numerical simulation method for shear seepage provides a powerful means to uncover the dynamic evolution mechanisms governing fracture permeability. 展开更多
关键词 Discrete element method(DEM) Finite element method(FEM) Fracture Permeability Shear stress Joint roughness coefficient(JRC) Dynamic evolution
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Single-cell multi-omics sequencing reveals cell-specific transcriptomic and chromatin accessibility profiles in gut microbiome metabolite butyrate-produced pain modulation 认领 引用
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作者 Ran Tao Sufang Liu +3 位作者 Joshua Crawford Phillip Kramer Steven Bender Feng Tao 《International Journal of Oral Science》 SCIE CAS CSCD 2026年第3期504-520,共17页
Pain is the most common symptom of temporomandibular joint(TMJ)disorders,which present significant clinical challenges due to their complexity and limited treatment options.Our previous study demonstrates that gut mic... Pain is the most common symptom of temporomandibular joint(TMJ)disorders,which present significant clinical challenges due to their complexity and limited treatment options.Our previous study demonstrates that gut microbiome-derived butyrate is critical for the modulation of TMJ pain.In this study,we investigated its underlying mechanisms,and we found that oral administration of tributyrin,a prodrug of butyrate,not only significantly alleviated TMJ pain but also reversed the reduction in histone acetylation in the spinal trigeminal nucleus caudalis(Sp5C)under the TMJ pain condition.Using single-cell multi-omics sequencing,we profiled gene expression and chromatin accessibility in the Sp5C cells at the single-cell resolution.Bioinformatics analysis revealed that TMJ pain disrupted both the expression and chromatin accessibility of Nop14,Matk,Idh3b,Ndst2,and Tomm6 across four cell types in the Sp5C,and these alterations were reversed by tributyrin treatment.Specifically,Nop14 exhibited increased chromatin accessibility at its promoter region under TMJ pain condition,and knockdown of Nop14 in the Sp5C restored histone acetylation and alleviated TMJ pain.Together,our findings reveal cell-type-specific gene regulation that underlies butyrate-mediated epigenetic regulation of TMJ pain,which suggesting that targeting gut microbiome metabolites could develop a non-opioid novel therapy for TMJ disorders. 展开更多
关键词 temporomandibular joint pain butyrate gut microbiome single cell multi omics sequencing epigenetic regulation nociceptive processing histone acetylation temporomandibular joint tmj disorderswhich
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Expert consensus on treatment of condylar hyperplasia and secondary dento-maxillofacial deformities 认领 引用
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作者 Ruiye Bi Bassam M.Abotaleb +39 位作者 Xiaofeng Bai Kun Cao Gang Chen Jie Cheng Weihua Guo Min Hu Li Huang Xuanping Huang Hongbing Jiang Lingyong Jiang Xiaolei Jin Feiwu Kang Tangxin Li Wenyang Li Shuguang Liu Yanpu Liu Yanshan Liu Li Lu Yisen Shao Bin Shi Guodong Song Yuxiong Su Jian Sun Zhenglong Tang Lei Tian Maimaitituxun Tuerdi Qilong Wan Xiaoxia Wang Xuejiu Wang Yong Wang Guomin Wu Zhijian Xie Guangqi Yan Xuewen Yang Meng You Fenghe Zhang Shilei Zhang Guangsen Zheng Songsong Zhu En Luo 《International Journal of Oral Science》 SCIE CAS CSCD 2026年第3期347-356,共10页
Condylar hyperplasia(CH),characterized by progressive facial deviation,occlusion disorders,and temporomandibular joint dysfunction,often requires combined temporomandibular joint(TMJ)-orthognathic interventions to rec... Condylar hyperplasia(CH),characterized by progressive facial deviation,occlusion disorders,and temporomandibular joint dysfunction,often requires combined temporomandibular joint(TMJ)-orthognathic interventions to reconstruct joint and occlusal functions as well as rebuilding harmonious facial expressions.Managing the dentomaxillofacial deformities secondary to CH involves hyperplastic condylar resection,orthognathic surgery,facial contour surgery and orthodontic treatment.Based on the activity of condylar hypertrophy,the severity of dentomaxillofacial deformity and malocclusion,an individualized treatment plan should be formulated to reconstruct joint functions,correct deformities and recover occlusal relationships.This expert consensus,informed by the latest clinical research and practical experience,addresses clinical considerations for surgical treatment strategies for patients with different CH types,delineating indications,objectives,procedures,and principles with the aim of providing clear and practical guidance for clinical practitioners. 展开更多
关键词 condylar hyperplasia ch characterized reconstruct joint occlusal functions condylar hy orthodontic treatmentbased hyperplastic condylar resectionorthognathic surgeryfacial contour surgery dentomaxillofacial deformities temporomandibular joint dysfunctionoften progressive facial deviationocclusion disordersand
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Modeling of bolted beam utilizing modified joint element and identification of contact parameters at the joint 认领 引用
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作者 Xiang Li Zhousuo Zhang +1 位作者 Zhuofan Zhou Dian Chen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2026年第2期374-382,共9页
Research on the modeling of bolted connection structures primarily centers on the characterization of the connection interface.Accurate equivalent modeling of the connection interface is crucial for the effective mode... Research on the modeling of bolted connection structures primarily centers on the characterization of the connection interface.Accurate equivalent modeling of the connection interface is crucial for the effective modeling of bolted connection structures.This article considers the misalignment between the bolt plane and the beam plane,and establishes a modified joint element representing the bolted connection by using the seriesstiffness method.The contact stiffness in this modified joint element are identified using a genetic algorithm with an “emperor selection” strategy.The bolted connection beam model is achieved by refining the Euler-Bernoulli beam model through the incorporation of a modified joint element.The maximum error between the model calculation results and experimental results for each order of natural frequency is 2.39%.This demonstrates the feasibility of accurately characterizing the bolted connection beam through the utilization of the modified joint element for equivalent modeling.This research proposes a modeling method for bolted connection beams that accounts for the misalignment between the bolt plane and the beam plane,significantly enhancing modeling accuracy. 展开更多
关键词 Bolted joints Modified joint element Genetic algorithm Parameter identification
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Stress characteristics and sealing mechanism of steel-titanium heterogeneous drill pipe joints 认领 引用
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作者 Feng Chen Jia-Qing Liu +4 位作者 Shang-Ying Yang Su-Na Zhang Jia-Nan Zhang Wen-Chang Wang Qin-Feng Di 《Petroleum Science》 SCIE EI CAS CSCD 2026年第6期3647-3666,共20页
Titanium alloy drill pipes exhibit promising potential for ultra-deep well drilling due to their high specific strength and superior corrosion resistance.However,the engagement surfaces of the pin and box joints featu... Titanium alloy drill pipes exhibit promising potential for ultra-deep well drilling due to their high specific strength and superior corrosion resistance.However,the engagement surfaces of the pin and box joints feature distinct material stiffness and surface roughness,which influence both the load bearing characteristics and sealing performance.This study establishes a 3D elastoplastic finite element model for steel-titanium heterogeneous drill pipe joints and analyzes their stress distribution under complex loading conditions.Furthermore,a sealing performance evaluation model based on microscopic leakage mechanisms is proposed,and the sealing performance of single shoulder and double shoulder drill pipe joints is comparatively analyzed.The results indicate that,compared to the NC50single-shoulder joint,the DS50 double-shoulder joint exhibits a 12.8%improvement in sealing performa nce under an axial tension of 2500 kN,and a 27.6%improvement under combined loading of 2500 kN axial tension and 8 kN·m bending moment.The synergistic action of the primary and secondary shoulders enhances the sealing stability of the drill pipe joint. 展开更多
关键词 Drill pipe joints Steel-titanium heterogeneity Complex loading Sealing model Sealing performance
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Numerical manifold method with joint elements for jointed tunnel stability analysis 认领 引用
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作者 Keqin ZHANG Wei WU +3 位作者 Yu WANG Baosheng DONG Lianyang ZHANG Hehua ZHU 《ENGINEERING Structure and Civil Engineering》 SCIE EI CAS CSCD 2026年第3期482-492,共11页
When conducting simulations of jointed rock mass tunnels,the conventional Numerical Manifold Method(NMM)relies on contact algorithms entailing intricate contact detection and open-close iteration processes,thereby lea... When conducting simulations of jointed rock mass tunnels,the conventional Numerical Manifold Method(NMM)relies on contact algorithms entailing intricate contact detection and open-close iteration processes,thereby leading to restricted computational efficiency.To overcome this constraint,this study puts forward a Joint Element-based Numerical Manifold Method(JE-NMM),which aims to improve the existing situation.The method replaces traditional contact algorithms with joint elements characterized by cohesive constitutive models and incorporates a Newton–Raphson iterative convergence strategy,thus establishing a static analysis framework that is suitable for initially closed joint systems.Results from numerical benchmark tests demonstrate that the new method attains approximately 20-fold higher computational efficiency compared to the classical NMM while preserving a high degree of consistency with the results of physical model test results in stability analysis of jointed tunnel.Findings from engineering application studies show that a locally optimized support scheme,by precisely identifying instability zones,can achieve reinforcement effects comparable to full-face bolting while significantly decreasing the number of bolts used.This approach effectively overcomes the efficiency-related constraints imposed by traditional contact algorithms,providing a novel numerical tool for stability analysis and support optimization in jointed rock tunnels. 展开更多
关键词 NMM cohesive zone model jointed tunnel stability localized bolt support
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Fretting Fatigue Behavior of Ti-6Al-4V Alloy Bolted Joints with Bolted Connection Features in Aero-engines 认领 引用
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作者 Chen Wang Yibo Shang +3 位作者 Yue Su Liucheng Zhou Weifeng He Bin Li 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2026年第2期176-189,共14页
Fretting fatigue in bolted joints within aero-engine fan and compressor structures,characterized by multi-layered,thin-walled components and high preload,poses a significant structural safety challenge.This study inve... Fretting fatigue in bolted joints within aero-engine fan and compressor structures,characterized by multi-layered,thin-walled components and high preload,poses a significant structural safety challenge.This study investigates fretting fatigue in a bolted joint configuration simulating compressor axis contact with sealing disk ends,analyzing hysteresis loops,fretting scars,and fracture surfaces.Numerical simulation,incorporating a UMESHMOTION subroutine,and a critical plane approach utilizing the Smith-Watson-Thorpe parameter and Miner’s law,alongside wear morphology simulation,were employed to evaluate fretting fatigue life.Results revealed a non-monotonic relationship between surface quality and fretting fatigue life,demonstrating an initial life decrease followed by an increase,primarily due to a transition from partial to gross slip.The study highlights the significant impact of fretting on the life prediction of aero-engine bolted joints,demonstrating that improved surface quality does not always guarantee enhanced fatigue performance.The accuracy of the life prediction approach was validated through experimental correlation with wear-aware simulation results. 展开更多
关键词 Fretting fatigue Failure analysis Bolted joint Surface roughness Aero-engine
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Dynamic mechanical behaviors and wave propagation characteristics of single fluid-filledrock joints under normal incidence of highintensity stress waves 认领 引用
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作者 Hui Yang Huan-Feng Duan +1 位作者 Qi Zhao Jianbo Zhu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2026年第7期5342-5362,共21页
The interaction of high-intensity stress waves with fluid-filledrock joints is pivotal in seismic hazard assessment,hydrocarbon recovery,geological CO2 storage,geothermal energy extraction,and wastewater disposal,yet ... The interaction of high-intensity stress waves with fluid-filledrock joints is pivotal in seismic hazard assessment,hydrocarbon recovery,geological CO2 storage,geothermal energy extraction,and wastewater disposal,yet remains insufficientlyunderstood.This study investigates the dynamic mechanical response(elastic modulus and initial joint stiffness)and wave propagation behavior(transmission and reflectioncoefficientsand energy attenuation)of single fluid-filledrock joints subjected to the normal incidence of high-intensity stress waves.Dynamic compression experiments were performed using a split Hopkinson pressure bar(SHPB)system combined with high-speed photography on individual fluid-filledrock joints with varying thickness,initial contact area,and water content.Results show that thinner joints,larger contact areas,and higher water contents yield greater dynamic elastic modulus and initial joint stiffness.Increasing stiffness consistently enhances wave transmission and suppresses wave reflection,independent of joint geometry or water saturation.Wave attenuation is strongly dependent on stiffness at low water contents,but this effect diminishes as the water content increases.High-speed imaging further reveals that the observed wave signatures arise from coupled mechanisms of joint stiffening and wave-induced fluidflow(WIFF).Energy partitioning derived from high-speed imaging data reveals the influenceof joint geometry on fluidflow-driven dissipation during stress wave propagation.This study advances the fundamental understanding of high-intensity stress waves–fluid-filledrock joints interactions,providing valuable insights for theoretical development and practical applications across many geophysical and geomechanical fields. 展开更多
关键词 Fluid-filledrock joint High-intensity stress wave Wave propagation and attenuation Joint stiffness Wave-induced fluidflow(WIFF)
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Busan Atmosphere Cryosphere Ocean Conference BACO-25:Our Interconnected Earth 认领 引用
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作者 Keith ALVERSON Silvia BLANC +1 位作者 Richard ESSERY Myong-In LEE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2026年第5期1095-1101,共7页
The IUGG Associations for Atmosphere,Oceans and Cryosphere—IAMAS,IAPSO and IACS—held a Joint Scientific Assembly in Busan,South Korea,from 20 to 25 July 2025.This was the first joint assembly of all three associatio... The IUGG Associations for Atmosphere,Oceans and Cryosphere—IAMAS,IAPSO and IACS—held a Joint Scientific Assembly in Busan,South Korea,from 20 to 25 July 2025.This was the first joint assembly of all three associations since 2009,when they met in Montreal,Canada.It was the first time any of the associations had been hosted in Korea,and it had been two decades since any of them had met in Asia.The choice of Busan as the venue supported high levels of participation and smooth conference operations.The Local Organizing Committee,chaired by Prof.Kyung-Ja Ha of Pusan National University,oversaw the successful organization of the event.The assembly brought together 1725 participants in total,including 1282 researchers and 443 invited participants and individuals involved in side events,exhibitions,media coverage,and volunteer work.Participants came from 46 countries across Asia,Europe,North America,South America,Africa,and Oceania.IAMAS had 736 participants,IAPSO 321,and IACS 225.Survey data from 951 respondents revealed that Early Career Scientists,defined as those within 10 years of receiving their PhD,accounted for approximately 25%of participants.The demographic profile skewed young,with 66%of attendees in their 20s and 30s.The scientific program was organized by Prof.Seon-Ki Park(Chair),the Secretaries General from all three Associations,and the Local Organizing Committee.Reflecting the theme“Our Interconnected Earth,”the scientific program emphasized integrated approaches to climate systems,addressing climate change and environmental challenges through collaborative,transdisciplinary research. 展开更多
关键词 Interconnected Earth IAMAS Busan joint assembly Atmosphere Ocean Conference Cryosphere
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Shear performance of NPR bolt under varying prestress levels 认领 引用
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作者 Wenhui Bian Kexue Wang +3 位作者 Jun Yang Qingshuo Hao Zhaoxi Zhai Xuefei Hong 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2026年第1期528-541,共14页
The negative Poisson’s ratio(NPR)bolt is an innovative support element distinguished by its high strength,elongation,and a slightly negative Poisson’s ratio.Unlike conventional prestressed(PR)bolts with a positive P... The negative Poisson’s ratio(NPR)bolt is an innovative support element distinguished by its high strength,elongation,and a slightly negative Poisson’s ratio.Unlike conventional prestressed(PR)bolts with a positive Poisson’s ratio,the NPR bolt exhibits a quasi-ideal plastic response without a prominent yield platform,enabling it to sustain high prestress with a substantial safety margin,which is particularly advantageous for jointed rock masses.However,investigations into the shear resistance mechanisms of NPR bolts under varying prestress levels remain limited.This study conducted full-scale double shear tests to assess the shear strength,deformation behavior,energy absorption,and failure mechanisms of NPR bolts under different prestress conditions.To ensure a fair comparison with PR bolts,a prestress utilization coefficient(PUC)was introduced.The results reveal that at a PUC of 0.25,the NPR bolt achieved peak axial force,shear displacement,and peak shear force values that are 2.41,1.88,and 2.13 times greater than those of the PR bolt,respectively.Shear performance was optimized at a prestress level of 100 kN,with energy absorption reaching 47.1 kJ,which is 2.8 times that of the PR bolt.Furthermore,the necking ratio was significantly reduced,indicating more distributed plastic deformation and delayed failure.Field applications verified the superior performance,resulting in a 27.4%reduction in roof settlement and enhanced structural integrity.These findings confirm that NPR bolts possess excellent shear resistance,energy absorption,and deformation adaptability,and optimizing prestress significantly enhances their support performance,providing a strong basis for geotechnical engineering applications. 展开更多
关键词 NPR bolt Jointed rock mass Prestressed force Shear test Shear performance
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Elastic-plastic nonlinear contact model for rough interfaces based on monotonically continuous contact pressure 认领 引用
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作者 Bo Li Yufan Zhang +4 位作者 Sanmin Wang Yesen Fan U.Xuan Tan Gantes J.Charis Jihong Zhu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2026年第3期237-247,共11页
The contact pressure of an asperity is the fundamental parameter for constructing a single asperity contact model and analyzing the contact load and contact stiffness of the mechanical joint surfaces.In response to th... The contact pressure of an asperity is the fundamental parameter for constructing a single asperity contact model and analyzing the contact load and contact stiffness of the mechanical joint surfaces.In response to the defects of existing models in contact pressure analysis that have non-monotonic changes or do not conform to physical laws,this paper proposes a novel nonlinear contact model that can achieve continuous monotonic changes in contact pressure in accordance with physical laws.This model considers the continuous deformation of the asperity after load application,and can describe three deformation states:elastic,elastic-plastic,and plastic during the loading process.For the elastic and plastic deformation stages,this paper characterizes them using the classic Hertz elastic contact theory and the complete plastic contact theory.For the elastic-plastic deformation stage,the contact pressure is characterized using an empirical pressure function,and expressions for other contact parameters are derived.Furthermore,based on the principle of probability and statistics,the solution expression for the contact parameters of the rough interface is obtained,and a novel rough interface contact model is established.By comparing with existing experimental and simulation results,it is found that:1)The model in this paper achieves monotonic and continuous changes in contact pressure during the contact process of the asperity,while complying with physical laws;2)The new model is in good agreement with experimental and simulation results,verifying the universal effectiveness and correctness of the proposed model in solving the contact parameters of the rough interface;3)The new model has simplicity in expression and high computa-tional efficiency. 展开更多
关键词 Asperity Mechanical joint surface Elastic-plastic deformation Statistics Numerical calculation
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Revealing the dominant influenceof joints:Soil-structurecomponent-joint adaptivity for prefabricated underground structures 认领 引用
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作者 Tong Qiu Kaibin Ye +3 位作者 Xiangsheng Chen Tianjun Wu Wei Rao Xiaohua Bao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2026年第7期5468-5488,共21页
Compared to the traditional cast-in-situ technique,the novel prefabricated underground structure(PUS)employs machinery excavation and assembly.Notably,the PUS assembly system undergoes multi-level force transmission t... Compared to the traditional cast-in-situ technique,the novel prefabricated underground structure(PUS)employs machinery excavation and assembly.Notably,the PUS assembly system undergoes multi-level force transmission through soil,structure,component,and joint interactions.This transmission mechanism remains inadequately understood,consequently posing frequent instability risks during PUS construction.Hereby,this study foremost addresses this problem for multi-level information modeling and planning for PUS under joint principal control.Three modules of numerical modeling,design theory and adaptive planning were constructed and integrated into the Soil-structure-component-joint Adaptive Planning Model(SAPM).Through a real-project application of SAPM,key insights are as follows:(1)SAPM achieves multi-level information adaptivity by planning the joint properties,which mitigates the soil-structure interaction effect of main and secondary structures by 18% and 63%,respectively.(2)Different joints and components may not achieve optimum solutions with uniform joint properties.Top,bottom and midslab joints achieve multi-level information adaptivity only when their respective joint stiffness factors are 0.90,0.61 and 0.65.(3)The use of semi-rigid joints in PUS has multiple advantages over the common cast-in-situ rigid joints.The semi-rigid scheme reduces ring assembly time and cost by approximately 40%and 20%,respectively,compared to hinged and rigid joint schemes.The research results provide a theoretical and instrumental basis for the safe construction of PUS in complex urban and geotechnical environments. 展开更多
关键词 Prefabricated underground structures Soil-structure-component-joint adaptivity Multi-level information planning Automatic modeling Semi-rigid joint
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