Understanding the mechanical behavior of diagenetic mineral granules and interfaces in granite provides essential experimental references for constructing micromechanical models of granite.The micromechanical behavior...Understanding the mechanical behavior of diagenetic mineral granules and interfaces in granite provides essential experimental references for constructing micromechanical models of granite.The micromechanical behavior of Yanshanian granite is investigated using scanning electron microscopy-energy dispersive spectroscopy(SEM-EDS)and nanoindentation tests.The results demonstrate transitional mechanical properties at mineral interfaces.The elastic modulus and hardness exhibit intermediate values between adjacent mineral phases.The higher plasticity indices at the interfaces suggest higher plastic deformation capacity of hard-phase minerals in these regions.Additionally,fracture toughness measurements of minerals and interfaces were obtained,with interfacial values ranging from 0.90 to 1.63 MPa·m^(0.5).The analysis of mechanical property relationships shows a significant positive linear correlation between rock-scale elastic modulus and fracture toughness.However,this correlation is substantially lower at the mineral scale,demonstrating a scale effect in the relationship of different mechanical properties.展开更多
On May 9,2025 on the campus of the University of Science and Technology of China(USTC),Chinese Academy of Sciences(CAS),an exhibition was unveiled to celebrate the UN International Year of Quantum Science and Technolo...On May 9,2025 on the campus of the University of Science and Technology of China(USTC),Chinese Academy of Sciences(CAS),an exhibition was unveiled to celebrate the UN International Year of Quantum Science and Technology(IYQ)-a one-year-long worldwide event in memory of the founding of quantum mechanics(QM).展开更多
The integration of physics-based modelling and data-driven artificial intelligence(AI)has emerged as a transformative paradigm in computational mechanics.This perspective reviews the development and current status of ...The integration of physics-based modelling and data-driven artificial intelligence(AI)has emerged as a transformative paradigm in computational mechanics.This perspective reviews the development and current status of AI-empowered frameworks,including data-driven methods,physics-informed neural networks,and neural operators.While these approaches have demonstrated significant promise,challenges remain in terms of robustness,generalisation,and computational efficiency.We delineate four promising research directions:(1)Modular neural architectures inspired by traditional computational mechanics,(2)physics informed neural operators for resolution-invariant operator learning,(3)intelligent frameworks for multiphysics and multiscale biomechanics problems,and(4)structural optimisation strategies based on physics constraints and reinforcement learning.These directions represent a shift toward foundational frameworks that combine the strengths of physics and data,opening new avenues for the modelling,simulation,and optimisation of complex physical systems.展开更多
The low-temperature embrittlement limits the service temperature of ferritic and duplex stainless steels.The effects of alloying elements added to Fe-Cr binary system on the low-temperature embrittlement have been rev...The low-temperature embrittlement limits the service temperature of ferritic and duplex stainless steels.The effects of alloying elements added to Fe-Cr binary system on the low-temperature embrittlement have been reviewed critically.Prior literature on the underlying phase transformation,i.e.,phase separation(PS)and changes of mechanical properties,is surveyed.The available literature indicates that the rate of PS is accelerated by Ni or Co in Fe-Cr binary system.The increased kinetics of PS also lead to an enhanced hardening rate during aging for Ni and Co alloyed Fe-Cr alloys.In low Cr(<17 wt.%)ferritic alloys,the additions of Al or Co can reduce embrittlement because these elements contribute to lowering the driving force for PS.The influence of other alloying elements such as Mo,Cu,Mn,Nb,and Ti is inconclusive but also discussed here.Thermodynamic and kinetic calculations were performed to evaluate current CALPHAD databases and to further investigate the thermodynamic and kinetic reasons for the effect of the additional alloying elements added to Fe-Cr alloy on PS.Some indications were provided for improving physically-based predictions of low-temperature embrittlement as well as opportunities to mitigate the phenomenon by alloying.展开更多
We are pleased to introduce this special thematic section on Nanofluid Mechanics and Heat Transfer that is being included in Acta Mechanica Sinica(AMS).This thematic issue consists of 6 papers selected from papers tha...We are pleased to introduce this special thematic section on Nanofluid Mechanics and Heat Transfer that is being included in Acta Mechanica Sinica(AMS).This thematic issue consists of 6 papers selected from papers that were presented at the 18th International Symposium on Numer-ical Analysis of Fluid Flows,Heat and Mass Transfer-Nu-merical Fluids 2023,held in Heraklion,Crete Greece,11-17 September 2023,and invited through a general call.The symposium covers various subjects:from new numerical methods and fundamental research until engineering appli-cations,and it is a part of the International Conference of Numerical Analysis and Applied Mathematics(ICNAAM),held annually.展开更多
Multi⁃field coupling problems involving species transport,heat transfer,substance transformation,and mechanical deformation are prevalent in various scenarios,such as the curing of early⁃age concretes,the response of ...Multi⁃field coupling problems involving species transport,heat transfer,substance transformation,and mechanical deformation are prevalent in various scenarios,such as the curing of early⁃age concretes,the response of soft materials,the oxidation of metals,the lithiation and delithiation of lithium⁃ion batteries,and the self⁃healing of biological tissues.Thermo⁃chemo⁃mechanical coupling dynamics are common characteristics of these problems,making theoretical studies on such processes of significant importance.This study offers a thorough review of advanced theoretical models that address thermo⁃chemo⁃mechanical behavior of solid materials within the theoretical framework of non⁃equilibrium thermodynamics.First,we outline the thermo⁃chemo⁃mechanical coupling phenomena observed in various application scenarios.Then,the theoretical developments of classical continuum mechanics include the phase field method and peridynamics in the contexts of thermo⁃mechanical coupling,chemo⁃mechanical coupling,and thermo⁃chemo⁃mechanical coupling,respectively.Finally,challenges faced by thermo⁃chemo⁃mechanical coupling research are highlighted and prospects and directions for this field are also outlined.This paper helps to understand the history and trends in the development of thermo⁃chemo⁃mechanical coupling theory.展开更多
The mechanical properties of biological soft tissues play a critical role in the study of biomechanics and the development of protective measures against human injury.Various testing techniques at different scales hav...The mechanical properties of biological soft tissues play a critical role in the study of biomechanics and the development of protective measures against human injury.Various testing techniques at different scales have been employed to characterize the mechanical behavior of soft tissues,which is essential for developing accurate tissue simulants and numerical models.This review comprehensively explores the mechanical properties of soft tissues,examining experimental methods,mechanical models,numerical simulations,and the progress in materials that mimic the mechanical performance of soft tissues.Finally,it reviews the damage and protection of human tissues under kinetic impacts,anticipating the future construction of soft tissue surrogate targets.The aim is to provide a systematic theoretical foundation and the latest advancements in the field,addressing the design,preparation,and quantitative modeling of biomimetic materials,thereby promoting the in-depth development of soft tissue mechanics and its applications.展开更多
Graphene,a two-dimensional material with atomic thickness,holds significant importance in advancing the existing theories of solid mechanics.However,as an intersection of multiple scales,it poses challenges to experim...Graphene,a two-dimensional material with atomic thickness,holds significant importance in advancing the existing theories of solid mechanics.However,as an intersection of multiple scales,it poses challenges to experimental measurements of its mechanical behaviors.This review comprehensively discusses the recent achievements in experimental studies on the mechanics of graphene,focusing on sample preparation,loading design,and measurement techniques.Moreover,personal perspectives on the future development in this field are presented,aiming to provide insights and inspiration for researchers engaged in related studies.展开更多
In recent years,large language models(LLMs)have demonstrated immense potential in practical applications to enhance work efficiency and decision-making capabilities.However,specialized LLMs in the oil and gas engineer...In recent years,large language models(LLMs)have demonstrated immense potential in practical applications to enhance work efficiency and decision-making capabilities.However,specialized LLMs in the oil and gas engineering area are rarely developed.To aid in exploring and developing deep and ultra-deep unconventional reservoirs,there is a call for a personalized LLM on oil-and gas-related rock mechanics,which may handle complex professional data and make intelligent predictions and decisions.To that end,herein,we overview general and industry-specific LLMs.Then,a systematic workflow is proposed for building this domain-specific LLM for oil and gas engineering,including data collection and processing,model construction and training,model validation,and implementation in the specific domain.Moreover,three application scenarios are investigated:knowledge extraction from textural resources,field operation with multidisciplinary integration,and intelligent decision assistance.Finally,several challenges in developing this domain-specific LLM are highlighted.Our key findings are that geological surveys,laboratory experiments,field tests,and numerical simulations form the four original sources of rock mechanics data.Those data must flow through collection,storage,processing,and governance before being fed into LLM training.This domain-specific LLM can be trained by fine-tuning a general open-source LLM with professional data and constraints such as rock mechanics datasets and principles.The LLM can then follow the commonly used training and validation processes before being implemented in the oil and gas field.However,there are three primary challenges in building this domain-specific LLM:data standardization,data security and access,and striking a compromise between physics and data when building the model structure.Some of these challenges are administrative rather than technical,and overcoming those requires close collaboration between the different interested parties and various professional practitioners.展开更多
This paper presents a novel element differential method for modeling cracks in piezoelectric materials,aiming to simulate fracture behaviors and predict the fracture parameter known as the J-integral accurately.The me...This paper presents a novel element differential method for modeling cracks in piezoelectric materials,aiming to simulate fracture behaviors and predict the fracture parameter known as the J-integral accurately.The method leverages an efficient collocation technique to satisfy traction and electric charge equilibrium on the crack surface,aligning internal nodes with piezoelectric governing equations without needing integration or variational principles.It combines the strengths of the strong form collocation and finite element methods.The J-integral is derived analytically using the equivalent domain integral method,employing Green's formula and Gauss's divergence theorem to transform line integrals into area integrals for solving two-dimensional piezoelectric material problems.The accuracy of the method is validated through comparison with three typical examples,and it offers fracture prevention strategies for engineering piezoelectric structures under different electrical loading patterns.展开更多
In this research,we introduce an innovative approach that combines the Continuum Damage Mechanics-Finite Element Method(CDM-FEM)with the Particle Swarm Optimization(PSO)-based technique,to predict the Medium-Low-Cycle...In this research,we introduce an innovative approach that combines the Continuum Damage Mechanics-Finite Element Method(CDM-FEM)with the Particle Swarm Optimization(PSO)-based technique,to predict the Medium-Low-Cycle Fatigue(MLCF)life of perforated structures.First,fatigue tests are carried out on three center-perforated structures,aiming to assess their fatigue life under various strengthening conditions.These tests reveal significant variations in fatigue life,accompanied by an examination of crack initiation through the analysis of fatigue fracture surfaces.Second,an innovative fatigue life prediction methodology is applied to perforated structures,which not only forecasts the initiation of fatigue cracks but also traces the progression of damage within these structures.It leverages an elastoplastic constitutive model integrated with damage and a damage evolution model under cyclic loads.The accuracy of this approach is validated by comparison with test results,falling within the three times error band.Finally,we explore the impact of various strengthening techniques,including cross-sectional reinforcement and cold expansion,on the fatigue life and damage evolution of these structures.This is achieved through an in-depth comparative analysis of both experimental data and computational predictions,which provides valuable insights into the behavior of perforated structures under fatigue conditions in practical applications.展开更多
As a core course for the Engineering Cost major at Chongqing Institute of Engineering,Engineering Mechanics shoulders the dual mission of cultivating students’mechanical thinking,engineering practical abilities,and p...As a core course for the Engineering Cost major at Chongqing Institute of Engineering,Engineering Mechanics shoulders the dual mission of cultivating students’mechanical thinking,engineering practical abilities,and professional qualities.Centered on the deep integration of the outcome-based education(OBE)concept and curriculum-based ideological and political education,this paper systematically elaborates on the reform paths and implementation strategies from four dimensions-reconstruction of teaching content,innovation of assessment mechanisms,integration of ideological and political elements,and construction of teaching resources-by drawing on the teaching reform practices of Engineering Mechanics courses at multiple universities.Through modular teaching content design,a competency-oriented diversified assessment system,and a method of integrating ideological and political education with local characteristics and engineering case studies,the teaching objectives of“knowledge transmission,ability cultivation,and value shaping”are achieved in a three-in-one manner.Practical results indicate that after the reform,students’engineering practical abilities have significantly improved,with a course objective achievement rate exceeding 0.73,a 23%increase in student satisfaction with the course,and a 35%year-on-year increase in the number of awards won in professional competitions,providing a replicable paradigm for the teaching reform of engineering courses.展开更多
Considering the three typical phase-change related rock mechanics phenomena during drilling and production in oil and gas reservoirs,which include phase change of solid alkane-related mixtures upon heating,sand liquef...Considering the three typical phase-change related rock mechanics phenomena during drilling and production in oil and gas reservoirs,which include phase change of solid alkane-related mixtures upon heating,sand liquefaction induced by sudden pressure release of the over-pressured sand body,and formation collapse due to gasification of pore fillings from pressure reduction,this study first systematically analyzes the progress of theoretical understanding,experimental methods,and mathematical representation,then discusses the engineering application scenarios corresponding to the three phenomena and reveals the mechanical principles and application effectiveness.Based on these research efforts,the study further discusses the significant challenges,potential developmental trends,and research approaches that require urgent exploration.The findings disclose that various phase-related rock mechanics phenomena require specific experimental and mathematical methods that can produce multi-field coupling mechanical mechanisms,which will eventually instruct the control on resource exploitation,evaluation on disaster level,and analysis of formation stability.To meet the development needs of the principle,future research efforts should focus on mining more phase-change related rock mechanics phenomena during oil and gas resources exploitation,developing novel experimental equipment,and using techniques of artificial intelligence and digital twins to implement real-time simulation and dynamic visualization of phase-change related rock mechanics.展开更多
Significant advances in battery and fuel cell technologies over the past decade have catalyzed the transition toward electrified transportation systems and large-scale renewable energy integration.Concurrent with thes...Significant advances in battery and fuel cell technologies over the past decade have catalyzed the transition toward electrified transportation systems and large-scale renewable energy integration.Concurrent with these developments,the interdisciplinary role of mechanics has emerged as a critical research frontier.展开更多
With the advancement of micro-and nano-scale devices and systems,there has been growing interest in understanding material mechanics at small scales.Nanowires,as fundamental one-dimensional building blocks,offer signi...With the advancement of micro-and nano-scale devices and systems,there has been growing interest in understanding material mechanics at small scales.Nanowires,as fundamental one-dimensional building blocks,offer significant advantages for constructing micro/nano-electro-mechanical systems(MEMS/NEMS)and serve as an ideal platform for studying their size-dependent mechanical properties.This paper reviews the development and current state of nanowire mechanical testing over the past decade.The first part introduces the related issues of nanowire mechanical testing.The second section explores several key topics and the latest research progress regarding the mechanical properties of nanowires,including ultralarge elastic strain,large plastic strain,'smaller is stronger',cold welding,and ductile-to-brittle transition.Finally,the paper envisions future development directions,identifying possible research hotspots and application prospects.展开更多
As an intriguing interdisciplinary research field, cell and molecular biomechanics is at the cutting edge of mechanics in general and biomechanics in particular. It has the potential to provide a quantitative understa...As an intriguing interdisciplinary research field, cell and molecular biomechanics is at the cutting edge of mechanics in general and biomechanics in particular. It has the potential to provide a quantitative understanding of how forces and deformation at tissue, cellular and molecular levels affect human health and disease. In this article, we review the recent advances in cell and molecular biomechanics, examine the available computational and experimental tools, and discuss important issues including protein deformation in mechanotransduction, cell deformation and constitutive behavior, cell adhesion and migration, and the associated models and theories. The opportunities and challenges in cell and molecular biomechanics are also discussed. We hope to provide readers a clear picture of the current status of this field, and to stimulate a broader interest in the applied mechanics community.展开更多
Problems involving coupled multiple space and time scales offer a real challenge for conventional frame-works of either particle or continuum mechanics. In this paper, four cases studies （shear band formation in bulk...Problems involving coupled multiple space and time scales offer a real challenge for conventional frame-works of either particle or continuum mechanics. In this paper, four cases studies （shear band formation in bulk metallic glasses, spallation resulting from stress wave, interaction between a probe tip and sample, the simulation of nanoindentation with molecular statistical thermodynamics） are provided to illustrate the three levels of trans-scale problems （problems due to various physical mechanisms at macro-level, problems due to micro-structural evolution at macro/micro-level, problems due to the coupling of atoms/ molecules and a finite size body at micro/nano-level） and their formulations. Accordingly, non-equilibrium statistical mechanics, coupled trans-scale equations and simultaneous solutions, and trans-scale algorithms based on atomic/molecular interaction are suggested as the three possible modes of trans-scale mechanics.展开更多
Three recent breakthroughs due to AI in arts and science serve as motivation:An award winning digital image,protein folding,fast matrix multiplication.Many recent developments in artificial neural networks,particularl...Three recent breakthroughs due to AI in arts and science serve as motivation:An award winning digital image,protein folding,fast matrix multiplication.Many recent developments in artificial neural networks,particularly deep learning(DL),applied and relevant to computational mechanics(solid,fluids,finite-element technology)are reviewed in detail.Both hybrid and pure machine learning(ML)methods are discussed.Hybrid methods combine traditional PDE discretizations with ML methods either(1)to help model complex nonlinear constitutive relations,(2)to nonlinearly reduce the model order for efficient simulation(turbulence),or(3)to accelerate the simulation by predicting certain components in the traditional integration methods.Here,methods(1)and(2)relied on Long-Short-Term Memory(LSTM)architecture,with method(3)relying on convolutional neural networks.Pure ML methods to solve(nonlinear)PDEs are represented by Physics-Informed Neural network(PINN)methods,which could be combined with attention mechanism to address discontinuous solutions.Both LSTM and attention architectures,together with modern and generalized classic optimizers to include stochasticity for DL networks,are extensively reviewed.Kernel machines,including Gaussian processes,are provided to sufficient depth for more advanced works such as shallow networks with infinite width.Not only addressing experts,readers are assumed familiar with computational mechanics,but not with DL,whose concepts and applications are built up from the basics,aiming at bringing first-time learners quickly to the forefront of research.History and limitations of AI are recounted and discussed,with particular attention at pointing out misstatements or misconceptions of the classics,even in well-known references.Positioning and pointing control of a large-deformable beam is given as an example.展开更多
The predictive model and design of heavy-duty metal rubber shock absorber for the powertrains of heavy-load mining vehicles were investigated.The microstructural characteristics of the wire mesh were elucidated using ...The predictive model and design of heavy-duty metal rubber shock absorber for the powertrains of heavy-load mining vehicles were investigated.The microstructural characteristics of the wire mesh were elucidated using fractal graphs.A numerical model based on virtual fabrication technique was established to propose a design scheme for the wire mesh component.Four sets of wire mesh shock absorbers with various relative densities were prepared and a predictive model based on these relative densities was established through mechanical testing.To further enhance the predictive accuracy,a variable transposition fitting method was proposed to refine the model.Residual analysis was employed to quantitatively validate the results against those obtained from an experimental control group.The results show that the improved model exhibits higher predictive accuracy than the original model,with the determination coefficient(R^(2))of 0.9624.This study provides theoretical support for designing wire mesh shock absorbers with reduced testing requirements and enhanced design efficiency.展开更多
In order to analyze the pavement stress caused by vehicle bumping at an approach slab, a simplified four-wheeled bi- axle vehicle-moving model is proposed. The effect of damping and vibration reduction in the process ...In order to analyze the pavement stress caused by vehicle bumping at an approach slab, a simplified four-wheeled bi- axle vehicle-moving model is proposed. The effect of damping and vibration reduction in the process of vehicle-moving is not considered. Based on the position change of vehicle wheels at the approach slab, the vehicle dynamic vibration equations are summarized. Meanwhile, the undetermined coefficients of the vibration equations are obtained using the boundary and initial conditions of the vehicle. The analytical motion solutions of rear and front wheels at different stages are concluded. Consequently, a four-wheeled vehicle model is developed and vibration equations are provided, which can be used to analyze the impact of complicated stress on pavement. The results show that the excessive stress and stress concentration will occur at the approach slab, and it needs to be strengthened.展开更多
基金funded by the National Natural Science Foundation of China(Nos.52422403 and U22A20166)the Deep Earth Probe and Mineral Resources Exploration-National Science and Technology Major Project(No.2024ZD1003903)+1 种基金the Department of Science and Technology of Guangdong Province(No.2019ZT08G315)Guangdong Basic and Applied Basic Research Foundation(No.2023A1515012654).
文摘Understanding the mechanical behavior of diagenetic mineral granules and interfaces in granite provides essential experimental references for constructing micromechanical models of granite.The micromechanical behavior of Yanshanian granite is investigated using scanning electron microscopy-energy dispersive spectroscopy(SEM-EDS)and nanoindentation tests.The results demonstrate transitional mechanical properties at mineral interfaces.The elastic modulus and hardness exhibit intermediate values between adjacent mineral phases.The higher plasticity indices at the interfaces suggest higher plastic deformation capacity of hard-phase minerals in these regions.Additionally,fracture toughness measurements of minerals and interfaces were obtained,with interfacial values ranging from 0.90 to 1.63 MPa·m^(0.5).The analysis of mechanical property relationships shows a significant positive linear correlation between rock-scale elastic modulus and fracture toughness.However,this correlation is substantially lower at the mineral scale,demonstrating a scale effect in the relationship of different mechanical properties.
文摘On May 9,2025 on the campus of the University of Science and Technology of China(USTC),Chinese Academy of Sciences(CAS),an exhibition was unveiled to celebrate the UN International Year of Quantum Science and Technology(IYQ)-a one-year-long worldwide event in memory of the founding of quantum mechanics(QM).
基金supported by the Australian Research Council(Grant No.IC190100020)the Australian Research Council Indus〓〓try Fellowship(Grant No.IE230100435)the National Natural Science Foundation of China(Grant Nos.12032014 and T2488101)。
文摘The integration of physics-based modelling and data-driven artificial intelligence(AI)has emerged as a transformative paradigm in computational mechanics.This perspective reviews the development and current status of AI-empowered frameworks,including data-driven methods,physics-informed neural networks,and neural operators.While these approaches have demonstrated significant promise,challenges remain in terms of robustness,generalisation,and computational efficiency.We delineate four promising research directions:(1)Modular neural architectures inspired by traditional computational mechanics,(2)physics informed neural operators for resolution-invariant operator learning,(3)intelligent frameworks for multiphysics and multiscale biomechanics problems,and(4)structural optimisation strategies based on physics constraints and reinforcement learning.These directions represent a shift toward foundational frameworks that combine the strengths of physics and data,opening new avenues for the modelling,simulation,and optimisation of complex physical systems.
基金support from the China Scholarship Council(CSC No.201700260207)Swedish Iron and Steel Research Office(Jernkontoret)The EIT RawMaterials Upscaling project EndureIT(No.18317)is acknowledged by PH and WM for financial support.
文摘The low-temperature embrittlement limits the service temperature of ferritic and duplex stainless steels.The effects of alloying elements added to Fe-Cr binary system on the low-temperature embrittlement have been reviewed critically.Prior literature on the underlying phase transformation,i.e.,phase separation(PS)and changes of mechanical properties,is surveyed.The available literature indicates that the rate of PS is accelerated by Ni or Co in Fe-Cr binary system.The increased kinetics of PS also lead to an enhanced hardening rate during aging for Ni and Co alloyed Fe-Cr alloys.In low Cr(<17 wt.%)ferritic alloys,the additions of Al or Co can reduce embrittlement because these elements contribute to lowering the driving force for PS.The influence of other alloying elements such as Mo,Cu,Mn,Nb,and Ti is inconclusive but also discussed here.Thermodynamic and kinetic calculations were performed to evaluate current CALPHAD databases and to further investigate the thermodynamic and kinetic reasons for the effect of the additional alloying elements added to Fe-Cr alloy on PS.Some indications were provided for improving physically-based predictions of low-temperature embrittlement as well as opportunities to mitigate the phenomenon by alloying.
文摘We are pleased to introduce this special thematic section on Nanofluid Mechanics and Heat Transfer that is being included in Acta Mechanica Sinica(AMS).This thematic issue consists of 6 papers selected from papers that were presented at the 18th International Symposium on Numer-ical Analysis of Fluid Flows,Heat and Mass Transfer-Nu-merical Fluids 2023,held in Heraklion,Crete Greece,11-17 September 2023,and invited through a general call.The symposium covers various subjects:from new numerical methods and fundamental research until engineering appli-cations,and it is a part of the International Conference of Numerical Analysis and Applied Mathematics(ICNAAM),held annually.
基金Sponsored by Guangdong Basic and Applied Basic Research Foundation(Grant No.2023A1515111166)Development and Reform Commission of Shenzhen(Grant No.XMHT20220103004)+1 种基金Shenzhen Natural Science Fund(Grant No.GXWD20231130100351002)National Natural Science Foundation of China(Grant No.11932005).
文摘Multi⁃field coupling problems involving species transport,heat transfer,substance transformation,and mechanical deformation are prevalent in various scenarios,such as the curing of early⁃age concretes,the response of soft materials,the oxidation of metals,the lithiation and delithiation of lithium⁃ion batteries,and the self⁃healing of biological tissues.Thermo⁃chemo⁃mechanical coupling dynamics are common characteristics of these problems,making theoretical studies on such processes of significant importance.This study offers a thorough review of advanced theoretical models that address thermo⁃chemo⁃mechanical behavior of solid materials within the theoretical framework of non⁃equilibrium thermodynamics.First,we outline the thermo⁃chemo⁃mechanical coupling phenomena observed in various application scenarios.Then,the theoretical developments of classical continuum mechanics include the phase field method and peridynamics in the contexts of thermo⁃mechanical coupling,chemo⁃mechanical coupling,and thermo⁃chemo⁃mechanical coupling,respectively.Finally,challenges faced by thermo⁃chemo⁃mechanical coupling research are highlighted and prospects and directions for this field are also outlined.This paper helps to understand the history and trends in the development of thermo⁃chemo⁃mechanical coupling theory.
基金supported by the National Natural Science Foundation of China(Grant No.U2241273)the Beijing Municipal Natural Science Foundation(Grant No.Z240017)+3 种基金the 111 project(Grant No.B13003)the Fundamental Research Funds for the Central Universitiesthe China Scholarship Councilthe Academic Excellence Foundation of BUAA for PhD Students.
文摘The mechanical properties of biological soft tissues play a critical role in the study of biomechanics and the development of protective measures against human injury.Various testing techniques at different scales have been employed to characterize the mechanical behavior of soft tissues,which is essential for developing accurate tissue simulants and numerical models.This review comprehensively explores the mechanical properties of soft tissues,examining experimental methods,mechanical models,numerical simulations,and the progress in materials that mimic the mechanical performance of soft tissues.Finally,it reviews the damage and protection of human tissues under kinetic impacts,anticipating the future construction of soft tissue surrogate targets.The aim is to provide a systematic theoretical foundation and the latest advancements in the field,addressing the design,preparation,and quantitative modeling of biomimetic materials,thereby promoting the in-depth development of soft tissue mechanics and its applications.
基金supported by the specialized research projects of Huanjiang Laboratory.
文摘Graphene,a two-dimensional material with atomic thickness,holds significant importance in advancing the existing theories of solid mechanics.However,as an intersection of multiple scales,it poses challenges to experimental measurements of its mechanical behaviors.This review comprehensively discusses the recent achievements in experimental studies on the mechanics of graphene,focusing on sample preparation,loading design,and measurement techniques.Moreover,personal perspectives on the future development in this field are presented,aiming to provide insights and inspiration for researchers engaged in related studies.
基金supported by the National Natural Science Foundation of China(no.42277122)the Science Foun-dation of the China University of Petroleum,Beijing(No.2462024BJRC013).
文摘In recent years,large language models(LLMs)have demonstrated immense potential in practical applications to enhance work efficiency and decision-making capabilities.However,specialized LLMs in the oil and gas engineering area are rarely developed.To aid in exploring and developing deep and ultra-deep unconventional reservoirs,there is a call for a personalized LLM on oil-and gas-related rock mechanics,which may handle complex professional data and make intelligent predictions and decisions.To that end,herein,we overview general and industry-specific LLMs.Then,a systematic workflow is proposed for building this domain-specific LLM for oil and gas engineering,including data collection and processing,model construction and training,model validation,and implementation in the specific domain.Moreover,three application scenarios are investigated:knowledge extraction from textural resources,field operation with multidisciplinary integration,and intelligent decision assistance.Finally,several challenges in developing this domain-specific LLM are highlighted.Our key findings are that geological surveys,laboratory experiments,field tests,and numerical simulations form the four original sources of rock mechanics data.Those data must flow through collection,storage,processing,and governance before being fed into LLM training.This domain-specific LLM can be trained by fine-tuning a general open-source LLM with professional data and constraints such as rock mechanics datasets and principles.The LLM can then follow the commonly used training and validation processes before being implemented in the oil and gas field.However,there are three primary challenges in building this domain-specific LLM:data standardization,data security and access,and striking a compromise between physics and data when building the model structure.Some of these challenges are administrative rather than technical,and overcoming those requires close collaboration between the different interested parties and various professional practitioners.
基金Financial support of this work by the Technology Development program of China(Grant No.2022204B003)National Natural Science Foundation of China(12272083 and 12172078)the Fundamental Research Funds for the Central Universities(DUT24YJ136)is gratefully acknowledged.
文摘This paper presents a novel element differential method for modeling cracks in piezoelectric materials,aiming to simulate fracture behaviors and predict the fracture parameter known as the J-integral accurately.The method leverages an efficient collocation technique to satisfy traction and electric charge equilibrium on the crack surface,aligning internal nodes with piezoelectric governing equations without needing integration or variational principles.It combines the strengths of the strong form collocation and finite element methods.The J-integral is derived analytically using the equivalent domain integral method,employing Green's formula and Gauss's divergence theorem to transform line integrals into area integrals for solving two-dimensional piezoelectric material problems.The accuracy of the method is validated through comparison with three typical examples,and it offers fracture prevention strategies for engineering piezoelectric structures under different electrical loading patterns.
基金support from the National Natural Science Foundation of China(No.12472072)the Fundamental Research Funds for the Central Universities,China.
文摘In this research,we introduce an innovative approach that combines the Continuum Damage Mechanics-Finite Element Method(CDM-FEM)with the Particle Swarm Optimization(PSO)-based technique,to predict the Medium-Low-Cycle Fatigue(MLCF)life of perforated structures.First,fatigue tests are carried out on three center-perforated structures,aiming to assess their fatigue life under various strengthening conditions.These tests reveal significant variations in fatigue life,accompanied by an examination of crack initiation through the analysis of fatigue fracture surfaces.Second,an innovative fatigue life prediction methodology is applied to perforated structures,which not only forecasts the initiation of fatigue cracks but also traces the progression of damage within these structures.It leverages an elastoplastic constitutive model integrated with damage and a damage evolution model under cyclic loads.The accuracy of this approach is validated by comparison with test results,falling within the three times error band.Finally,we explore the impact of various strengthening techniques,including cross-sectional reinforcement and cold expansion,on the fatigue life and damage evolution of these structures.This is achieved through an in-depth comparative analysis of both experimental data and computational predictions,which provides valuable insights into the behavior of perforated structures under fatigue conditions in practical applications.
文摘As a core course for the Engineering Cost major at Chongqing Institute of Engineering,Engineering Mechanics shoulders the dual mission of cultivating students’mechanical thinking,engineering practical abilities,and professional qualities.Centered on the deep integration of the outcome-based education(OBE)concept and curriculum-based ideological and political education,this paper systematically elaborates on the reform paths and implementation strategies from four dimensions-reconstruction of teaching content,innovation of assessment mechanisms,integration of ideological and political elements,and construction of teaching resources-by drawing on the teaching reform practices of Engineering Mechanics courses at multiple universities.Through modular teaching content design,a competency-oriented diversified assessment system,and a method of integrating ideological and political education with local characteristics and engineering case studies,the teaching objectives of“knowledge transmission,ability cultivation,and value shaping”are achieved in a three-in-one manner.Practical results indicate that after the reform,students’engineering practical abilities have significantly improved,with a course objective achievement rate exceeding 0.73,a 23%increase in student satisfaction with the course,and a 35%year-on-year increase in the number of awards won in professional competitions,providing a replicable paradigm for the teaching reform of engineering courses.
基金Supported by the National Natural Science Foundation of China(NSFC)Major Project(51991362).
文摘Considering the three typical phase-change related rock mechanics phenomena during drilling and production in oil and gas reservoirs,which include phase change of solid alkane-related mixtures upon heating,sand liquefaction induced by sudden pressure release of the over-pressured sand body,and formation collapse due to gasification of pore fillings from pressure reduction,this study first systematically analyzes the progress of theoretical understanding,experimental methods,and mathematical representation,then discusses the engineering application scenarios corresponding to the three phenomena and reveals the mechanical principles and application effectiveness.Based on these research efforts,the study further discusses the significant challenges,potential developmental trends,and research approaches that require urgent exploration.The findings disclose that various phase-related rock mechanics phenomena require specific experimental and mathematical methods that can produce multi-field coupling mechanical mechanisms,which will eventually instruct the control on resource exploitation,evaluation on disaster level,and analysis of formation stability.To meet the development needs of the principle,future research efforts should focus on mining more phase-change related rock mechanics phenomena during oil and gas resources exploitation,developing novel experimental equipment,and using techniques of artificial intelligence and digital twins to implement real-time simulation and dynamic visualization of phase-change related rock mechanics.
文摘Significant advances in battery and fuel cell technologies over the past decade have catalyzed the transition toward electrified transportation systems and large-scale renewable energy integration.Concurrent with these developments,the interdisciplinary role of mechanics has emerged as a critical research frontier.
基金supported by NSFC/RGC Joint Research Scheme(No.N_HKU159/22)Research Grants Council of the Hong Kong Special Administrative Region,China under Grant No.RFS2021-1S05.
文摘With the advancement of micro-and nano-scale devices and systems,there has been growing interest in understanding material mechanics at small scales.Nanowires,as fundamental one-dimensional building blocks,offer significant advantages for constructing micro/nano-electro-mechanical systems(MEMS/NEMS)and serve as an ideal platform for studying their size-dependent mechanical properties.This paper reviews the development and current state of nanowire mechanical testing over the past decade.The first part introduces the related issues of nanowire mechanical testing.The second section explores several key topics and the latest research progress regarding the mechanical properties of nanowires,including ultralarge elastic strain,large plastic strain,'smaller is stronger',cold welding,and ductile-to-brittle transition.Finally,the paper envisions future development directions,identifying possible research hotspots and application prospects.
基金supported by the National Heart,Lung,and Blood Institute,National Institutes of Health,as a Program of Excellence in Nanotechnology Award,N01 HV-08234,to Gang Baothe support from the National Natural Science Foundation of China through Grant Nos.10872115,11025208 and 10732050
文摘As an intriguing interdisciplinary research field, cell and molecular biomechanics is at the cutting edge of mechanics in general and biomechanics in particular. It has the potential to provide a quantitative understanding of how forces and deformation at tissue, cellular and molecular levels affect human health and disease. In this article, we review the recent advances in cell and molecular biomechanics, examine the available computational and experimental tools, and discuss important issues including protein deformation in mechanotransduction, cell deformation and constitutive behavior, cell adhesion and migration, and the associated models and theories. The opportunities and challenges in cell and molecular biomechanics are also discussed. We hope to provide readers a clear picture of the current status of this field, and to stimulate a broader interest in the applied mechanics community.
基金the National Basic Research Program of China (2007CB814800)the National Natural Science Foundation of China (10432050,10572139,10721202,10772012,10772181,90715001)CAS Innovation Program (KJCX2-SW-L08,KJCX2-YW-M04)
文摘Problems involving coupled multiple space and time scales offer a real challenge for conventional frame-works of either particle or continuum mechanics. In this paper, four cases studies （shear band formation in bulk metallic glasses, spallation resulting from stress wave, interaction between a probe tip and sample, the simulation of nanoindentation with molecular statistical thermodynamics） are provided to illustrate the three levels of trans-scale problems （problems due to various physical mechanisms at macro-level, problems due to micro-structural evolution at macro/micro-level, problems due to the coupling of atoms/ molecules and a finite size body at micro/nano-level） and their formulations. Accordingly, non-equilibrium statistical mechanics, coupled trans-scale equations and simultaneous solutions, and trans-scale algorithms based on atomic/molecular interaction are suggested as the three possible modes of trans-scale mechanics.
文摘Three recent breakthroughs due to AI in arts and science serve as motivation:An award winning digital image,protein folding,fast matrix multiplication.Many recent developments in artificial neural networks,particularly deep learning(DL),applied and relevant to computational mechanics(solid,fluids,finite-element technology)are reviewed in detail.Both hybrid and pure machine learning(ML)methods are discussed.Hybrid methods combine traditional PDE discretizations with ML methods either(1)to help model complex nonlinear constitutive relations,(2)to nonlinearly reduce the model order for efficient simulation(turbulence),or(3)to accelerate the simulation by predicting certain components in the traditional integration methods.Here,methods(1)and(2)relied on Long-Short-Term Memory(LSTM)architecture,with method(3)relying on convolutional neural networks.Pure ML methods to solve(nonlinear)PDEs are represented by Physics-Informed Neural network(PINN)methods,which could be combined with attention mechanism to address discontinuous solutions.Both LSTM and attention architectures,together with modern and generalized classic optimizers to include stochasticity for DL networks,are extensively reviewed.Kernel machines,including Gaussian processes,are provided to sufficient depth for more advanced works such as shallow networks with infinite width.Not only addressing experts,readers are assumed familiar with computational mechanics,but not with DL,whose concepts and applications are built up from the basics,aiming at bringing first-time learners quickly to the forefront of research.History and limitations of AI are recounted and discussed,with particular attention at pointing out misstatements or misconceptions of the classics,even in well-known references.Positioning and pointing control of a large-deformable beam is given as an example.
基金National Natural Science Foundation of China(12262028)Program for Young Talents of Science and Technology in Universities of Inner Mongolia Autonomous Region(NJYT22085)Inner Mongolia Autonomous Region Science and Technology Plan Project(2021GG0437)。
文摘The predictive model and design of heavy-duty metal rubber shock absorber for the powertrains of heavy-load mining vehicles were investigated.The microstructural characteristics of the wire mesh were elucidated using fractal graphs.A numerical model based on virtual fabrication technique was established to propose a design scheme for the wire mesh component.Four sets of wire mesh shock absorbers with various relative densities were prepared and a predictive model based on these relative densities was established through mechanical testing.To further enhance the predictive accuracy,a variable transposition fitting method was proposed to refine the model.Residual analysis was employed to quantitatively validate the results against those obtained from an experimental control group.The results show that the improved model exhibits higher predictive accuracy than the original model,with the determination coefficient(R^(2))of 0.9624.This study provides theoretical support for designing wire mesh shock absorbers with reduced testing requirements and enhanced design efficiency.
基金The Doctoral Program of Central South University (No. 2010ybfz048)the National High Technology Research and Development Program of China (863 Program) (No. 2007AA021908)
文摘In order to analyze the pavement stress caused by vehicle bumping at an approach slab, a simplified four-wheeled bi- axle vehicle-moving model is proposed. The effect of damping and vibration reduction in the process of vehicle-moving is not considered. Based on the position change of vehicle wheels at the approach slab, the vehicle dynamic vibration equations are summarized. Meanwhile, the undetermined coefficients of the vibration equations are obtained using the boundary and initial conditions of the vehicle. The analytical motion solutions of rear and front wheels at different stages are concluded. Consequently, a four-wheeled vehicle model is developed and vibration equations are provided, which can be used to analyze the impact of complicated stress on pavement. The results show that the excessive stress and stress concentration will occur at the approach slab, and it needs to be strengthened.
