Article
Mathematics, Applied
M. Jahangiri, M. Asghari
Summary: The non-classical continuum theory of strain gradient elasticity effectively captures small-scale effects in micro-structures. A formulation is developed to investigate the coupled torsional-flexural vibrations of micro-rotors considering inertia nonlinearities. The strain gradient theory predicts more reliable results for micro-rotors with thin shafts compared to classical continuum mechanics.
APPLIED MATHEMATICS AND COMPUTATION
(2023)
Article
Materials Science, Multidisciplinary
O. Hrytsyna, J. Sladek, V. Sladek, Q. Deng, M. Hrytsyna
Summary: The modified strain gradient theory (MSGT) is developed to analyze the free vibration of elastic centrosymmetric tubes. The theory considers flexoelectric and micro-inertia effects and includes various parameters such as strain, stretch gradient, rotation gradient, dilatation gradient, polarization vector, and electric quadrupoles. The governing equations and boundary conditions are derived from the Hamilton variation principle, and the torsional vibration problem is solved analytically for non-piezoelectric nanotubes with fixed edges. The study investigates the influence of nanotube geometry, flexoelectric coefficient, micro-inertia, and micro-stiffness parameters on the natural frequency.
MECHANICS OF ADVANCED MATERIALS AND STRUCTURES
(2023)
Article
Mechanics
Chaojie Mo, Dmitry A. Fedosov
Summary: The synchronization of two actuated sheets is influenced by the competition of inertial effects, sheet elasticity, fluid compressibility, and viscoelasticity. Fluid viscoelasticity plays a dominant role in enhancing synchronization, particularly for large beating amplitudes and Deborah numbers De>1, favoring the in-phase configuration. This study provides insights into the interactions between microswimmers and the factors affecting their collective behavior.
Article
Engineering, Geological
Niki D. Beskou, Edmond V. Muho
Summary: This study investigates the effects of microstructural on the dynamic response of rigid and flexible pavements to moving loads. The presence of a stiff plate in rigid pavements and a viscoelastic top layer in flexible pavements reduces microstructural effects on the pavement response, except for vehicle speeds close to the critical speed.
SOIL DYNAMICS AND EARTHQUAKE ENGINEERING
(2022)
Article
Materials Science, Multidisciplinary
Amir Parsian, Mahdi Eynian, Martin Magnevall, Tomas Beno
Summary: The use of coolant channels significantly improves drilling performance, but also reduces the stiffness of the drills, potentially affecting the quality of the drilled holes. A new method using Prandtl's stress function is proposed to predict stiffness values, showing that drills with two eccentric coolant channels have less reduction in stiffness compared to those with a single central channel. The method is also used to optimize the location of the eccentric coolant channels to minimize stiffness loss.
Article
Green & Sustainable Science & Technology
Majd Ahmad, Richard Ray
Summary: The damping ratio values of three different types of sand were measured using the Resonant Column-Torsional Simple Shear device. Three distinct methods were employed to estimate and compare the damping ratio values, and the results showed that the different methods provided accurate measurements under different strain conditions.
Article
Physics, Multidisciplinary
Reza Hassannejad, Mir Mohammad Ettefagh, Babak Alizadeh-Hamidi
Summary: This study investigates the simultaneous effect of warping function and elastic layer on the natural frequency of torsional vibration of nano-bars in the presence of a magnetic field. The study also analyzes the influence of elastic layer changes on the maximum frequency and warping function of nano-bars.
EUROPEAN PHYSICAL JOURNAL PLUS
(2022)
Article
Engineering, Mechanical
Roderic S. Lakes
Summary: Buckling leads to softening of the structural stiffness in columns and ribs, while pre-compression of foam materials results in decreased warping compared to classical elasticity predictions. Pre-compression also increases warping compared to non-pre-compressed materials, with this effect attributed to the release of stored energy during pre-compression.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2021)
Article
Engineering, Civil
Johann Facciorusso
Summary: Measurement of soil properties under cyclic and dynamic loading conditions is crucial in solving geotechnical earthquake engineering problems. Dynamic properties of soils, expressed in shear modulus (G) and damping ratio (D), are typically obtained from laboratory tests at different strain levels. Empirical relationships between dynamic parameters and routine geotechnical test measurements are commonly used, highlighting the importance of a large and reliable archive of testing results for geotechnical earthquake engineers and researchers.
EARTHQUAKE SPECTRA
(2021)
Article
Mechanics
Weidong Yang, Mingjia Liu, Siyu Chen, Wenbin Kang, Junwei Chen, Yan Li
Summary: This work proposes a self-sensing actuating composite structure for constructing an electrostatic torsional actuator. The composite nanobeams, modeled based on strain gradient theory, are capable of self-adjusting the pull-in tilting angle of the micro-actuator considering size dependency and damage. Theoretical and numerical results show good agreement and validate the accuracy of the proposed model. By introducing piezoelectric layers into laminated torsional structures, the working state and damage of the device can be sensed and driven by piezoelectric effect, enabling the adjustment and prediction of stability to avoid pull-in instability. This work contributes to the structural optimization of electromechanical devices.
COMPOSITE STRUCTURES
(2023)
Article
Engineering, Biomedical
Zheng Wang, Xiaolu Zhu, Xiuli Cong
Summary: This study introduces a scheme using maleimide-dextran hydrogel to modify the biomechanical properties of hMSCs. The experiment demonstrates that the hydrogel triggers the formation of multicellular spheroids and can soften hMSCs by adjusting the degree of stiffness variation, allowing them to pass through micro-channels more easily.
Article
Acoustics
Paul R. Heyliger, Clemens Junker, Karsten Meier, Ward L. Johnson
Summary: The vibrational modes of unrestrained elastic cylinders of trigonal crystals were studied. A revised working equation for torsional quartz viscometry was derived, incorporating effects of crystalline anisotropy. Numerical quantification of effects from different displacements was conducted, with implications for fluid viscosity extraction.
JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA
(2022)
Article
Chemistry, Multidisciplinary
Jun Zhu, Puying Hu, Yudan Chen, Shaowei Chen, Chuanzeng Zhang, Yanzheng Wang, Dongying Liu
Summary: This paper investigates the wave propagation in nano phononic crystals and finds that size-dependent effects have a significant influence on the waves propagating in phononic crystals in the nanoscale. Numerical examples reveal the effects of flexoelectricity, microstructure, and micro-inertia on the width and midfrequency of the band gaps. With increase in the size of the phononic crystal, the size effects gradually disappear.
Article
Engineering, Geological
Stephen K. Suryasentana, Paul W. Mayne
Summary: This paper introduces a novel work-equivalent framework for developing simplified design methods to estimate the stiffness of footings in nonhomogeneous soils. 3D finite element analyses were conducted to investigate the soil-footing interaction and validate the new design approach.
JOURNAL OF GEOTECHNICAL AND GEOENVIRONMENTAL ENGINEERING
(2022)
Article
Chemistry, Multidisciplinary
Hyoungwook Lee, Chul-Su Kim
Summary: This paper investigates the influence of diaphragm-type air springs in railway vehicles on the stability of high-speed trains. The study explores the effects of air bag shape, material, and ply angles on stiffness, and proposes a relationship between ply angle and radial position. The research finds that the vertical stiffness is minimally affected, but there is a significant impact on lateral and torsional stiffness.
APPLIED SCIENCES-BASEL
(2022)
Article
Engineering, Civil
Gabriele Fiorentino, Cihan Cengiz, Flavia De Luca, George Mylonakis, Dimitris Karamitros, Matt Dietz, Luiza Dihoru, Davide Lavorato, Bruno Briseghella, Tatjana Isakovic, Christos Vrettos, Antonio Topa Gomes, Anastasios Sextos, Camillo Nuti
Summary: Integral abutment bridges (IABs) have attracted renewed interest due to their low cost, but there is limited knowledge on their dynamic behavior and vulnerability under seismic actions. Therefore, experimental tests were conducted to investigate the seismic behavior of IABs in depth.
EARTHQUAKE ENGINEERING & STRUCTURAL DYNAMICS
(2021)
Article
Engineering, Civil
Michalis F. Vassiliou, Cihan Cengiz, Matt Dietz, Luiza Dihoru, Marco Broccardo, George Mylonakis, Anastasios Sextos, Bozidar Stojadinovic
Summary: This article introduces publicly available data from a series of 226 shake table tests of a 3D rocking podium structure, which can be used to statistically validate analytical and numerical models of rocking structures.
EARTHQUAKE SPECTRA
(2021)
Article
Engineering, Geological
Lawrence W. de Leeuw, Matthew S. Dietz, Henry Milewski, George Mylonakis, Andrea Diambra
Summary: Offshore pipelines commonly use polypropylene coating systems to protect against corrosion and provide thermal insulation. Axial stress in high pressure high temperature pipelines is influenced by friction between pipe coating material and seafloor soil. Accurate quantification of pipe-soil interface friction is essential for robust pipeline stability design.
CANADIAN GEOTECHNICAL JOURNAL
(2021)
Article
Engineering, Civil
Michalis F. Vassiliou, Cihan Cengiz, Matt Dietz, Luiza Dihoru, Marco Broccardo, George Mylonakis, Anastasios Sextos, Bozidar Stojadinovic
Summary: This article presents a set of earthquake engineering data for model validation, focusing on statistically validating different methods for modeling three-dimensional rocking structures.
EARTHQUAKE SPECTRA
(2021)
Article
Engineering, Geological
Elia Voyagaki, Jamie J. Crispin, Charlotte E. L. Gilder, Konstantina Ntassiou, Nick O'Riordan, Paul Nowak, Tarek Sadek, Dinesh Patel, George Mylonakis, Paul J. Vardanega
Summary: Reliable field data is crucial for the advancement of geotechnical engineering, especially in the case of piled foundations. This paper statistically assesses the uncertainty of predictions of pile performance under axial loading using a UK geotechnical database, comparing model bias and error to identify sources of uncertainty and evaluate model use in future geotechnical practice. The two models investigated in the study generally over-predict settlement, likely due to conservative parameter selection.
GEORISK-ASSESSMENT AND MANAGEMENT OF RISK FOR ENGINEERED SYSTEMS AND GEOHAZARDS
(2022)
Article
Engineering, Geological
Stefano Silvestri, Simonetta Baraccani, Dora Foti, Salvador Ivorra, Dimitris Theodossopoulos, Vitantonio Vacca, Jacqueline Ochoa Roman, Luca Cavallini, Elnaz Mokhtari, Rory White, Matt Dietz, George Mylonakis
Summary: A novel experimental study was conducted on the dynamic and seismic response of a 2m x 2m in plan - 0.7m in height groin vault model. The study revealed strong non-linear behavior of the model and identified that failure mechanisms and collapse accelerations mainly depend on base restraint conditions.
SOIL DYNAMICS AND EARTHQUAKE ENGINEERING
(2021)
Article
Engineering, Civil
Maria Giovanna Durante, Jonathan P. Stewart, Scott J. Brandenberg, George Mylonakis
Summary: Seismic earth pressures acting on basement walls and retaining walls are commonly computed using limit state methods, which fail to accurately represent the fundamental mechanisms. A simplified single-frequency procedure is proposed to compute seismic earth pressures applied to flexible retaining structures, considering wavelength and wall flexibility effects. The proposed solution provides lower earth pressure predictions compared to limit state solutions and shows good agreement with numerical simulations and centrifuge modeling.
EARTHQUAKE SPECTRA
(2022)
Article
Engineering, Geological
Abigail H. Bateman, Jamie J. Crispin, Paul J. Vardanega, George E. Mylonakis
Summary: Estimation of nonlinear pile settlement can be simplified by dividing soil into horizontal slices using one-dimensional t-z curves, reducing the analysis to a boundary-value problem. Theoretical t-z curves and new attenuation functions for shear stresses provide analytical solutions for soil settlement calculation.
JOURNAL OF GEOTECHNICAL AND GEOENVIRONMENTAL ENGINEERING
(2022)
Article
Engineering, Mechanical
Jamie J. Crispin, George Mylonakis
Summary: A novel exact analytical solution is derived for the equation y((4)) + x(n)y = 0, which is important for analyzing piles in soil with stiffness varying with depth. The paper proposes a novel approach for deriving Winkler spring moduli for combined force and moment loading, showing good agreement with numerical continuum results.
JOURNAL OF ENGINEERING MECHANICS
(2022)
Article
Engineering, Geological
Emmanouil Rovithis, George Mylonakis
Summary: This study investigates the response of an inhomogeneous soil layer with exponentially varying stiffness using one-dimensional viscoelastic wave propagation theory. Analytical treatment leads to an exact harmonic solution of the Bessel type, and findings demonstrate the relationship between strains, displacements, and stresses with depth. Novel asymptotic and approximate solutions are proposed for the base-to-surface transfer function, providing practical alternatives to the complex exact solution. New expressions relating shear strain and peak particle velocity, as well as curvature and peak ground acceleration near the soil surface, are derived.
JOURNAL OF GEOTECHNICAL AND GEOENVIRONMENTAL ENGINEERING
(2022)
Article
Engineering, Geological
Changjie Zheng, George Mylonakis, George Kouretzis, Lubao Luan
Summary: In this paper, a Tajimi-type continuum elastodynamic model is used to analytically model the kinematic interaction between a single pile and its surrounding soil under seismic shear waves. The model is validated against numerical simulations and an existing approximate solution. A parametric study is then conducted to investigate the sensitivity of the seismic response of piles to key problem parameters. The study provides closed-form expressions for pile deformations and soil resistance without requiring fitting coefficients.
SOIL DYNAMICS AND EARTHQUAKE ENGINEERING
(2022)
Article
Engineering, Geological
Francesco Di Michele, Enrico Spacone, Guido Camata, Giuseppe Brando, Anastasios Sextos, Adam Crewe, George Mylonakis, Matt Diez, Luiza Dihoru, Humberto Varum
Summary: This paper discusses the main results of a full-scale shaking table test campaign on three-leaf masonry walls with weak lime-mortar joints, which are commonly found in seismic prone regions in the Mediterranean area. The paper presents a preliminary study on the mechanical properties of the wall component materials and the design of the tested masonry wall. The main results of the experimental test, including damage patterns, drift ratios, and base shear, are discussed along with nonlinear numerical simulations that validated the experimental study.
BULLETIN OF EARTHQUAKE ENGINEERING
(2023)
Proceedings Paper
Construction & Building Technology
G. Fiorentino, D. Lavorato, C. Nuti, F. De Luca, C. Cengiz, A. Sextos, G. Mylonakis, B. Briseghella
Summary: Integral Abutment Bridges (IABs) reduce construction and maintenance costs by eliminating bearing supports and expansion joints, but the complex Soil-Structure Interaction (SSI) must be considered in design. While there have been many numerical studies globally, experimental tests are lacking and seismic design codes do not provide sufficient guidelines.
BRIDGE MAINTENANCE, SAFETY, MANAGEMENT, LIFE-CYCLE SUSTAINABILITY AND INNOVATIONS
(2021)
Article
Engineering, Civil
M. F. Vassiliou, M. Broccardo, C. Cengiz, M. Dietz, L. Dihoru, S. Gunay, K. M. Mosalam, G. Mylonakis, A. Sextos, B. Stojadinovic
Summary: The article discusses the unpredictability of rocking motion and verifies it through experiments. The experimentally obtained displacements were found to have statistically stable cumulative distribution functions (CDFs), and contestants in the blind prediction contest were able to relatively accurately predict the displacement CDFs. The performance of finite element and discrete element modeling approaches depends on input parameters and assumptions, with models without Rayleigh damping producing better predictions.
EARTHQUAKE ENGINEERING & STRUCTURAL DYNAMICS
(2021)
Article
Engineering, Geological
E. G. Psaroudakis, G. E. Mylonakis, N. S. Klimis
Summary: This paper analyzes the behavior of a monopile under lateral loading and develops a semi-analytical solution to calculate the lateral stiffness coefficients at the pile head with satisfactory accuracy, which converges well with real data and other theoretical results.
GEOTECHNICAL AND GEOLOGICAL ENGINEERING
(2021)
Article
Materials Science, Multidisciplinary
Yanzheng Wang, Qian Wu, Yiran Tian, Guoliang Huang
Summary: This paper proposes the microstructure design of an odd plate and investigates the directional wave energy amplification and the presence of interface waves in odd plates through theoretical and numerical analysis. The research findings contribute to the understanding of elastic behavior in 2D non-Hermitian systems.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
F. Greco, D. Codony, H. Mohammadi, S. Fernandez-Mendez, I. Arias
Summary: This study overcomes the difficulty of harnessing the flexoelectric effect by designing multiscale metamaterials. Through topology optimization calculations, we obtain optimal structures for various apparent piezoelectric properties and find that low-area-fraction lattices are the preferred choice. The results show competitive estimations of apparent piezoelectricity compared to reference materials such as quartz and PZT ceramics.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
Xiaoxuan Zhang, Tryaksh Gupta, Zhenlin Wang, Amalie Trewartha, Abraham Anapolsky, Krishna Garikipati
Summary: This study presents a computational framework for coupled electro-chemo-(nonlinear) mechanics at the particle scale in solid-state batteries, including interfacial fracture, degradation in charge transfer, and stress-dependent kinetics. The discontinuous finite element method allows for arbitrary particle shapes and geometries.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
Chengguan Zhang, Xavier Balandraud, Yongjun He
Summary: The coexistence of both austenite and martensite is a common characteristic in Shape Memory Alloys (SMAs). The multiple-domain microstructures, consisting of austenite, martensite twins, and individual martensite variants, evolve collectively during the phase transformation, affecting the material's macroscopic response. This paper presents an experimentally observed interface consisting of five domains in a Ni-Mn-Ga single-crystal, and analyzes the effects of thermal loading path and material initial state on the domain pattern formation.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
Shaobao Liu, Haiqian Yang, Guang-Kui Xu, Jingbo Wu, Ru Tao, Meng Wang, Rongyan He, Yulong Han, Guy M. Genin, Tian Jian Lu, Feng Xu
Summary: The balance between stress and adhesion plays a crucial role in governing the behaviors of adherent cells, such as cell migration. In certain microenvironments, such as tumor, variations in hydrostatic pressure can significantly impact cell volume and adhesion, which in turn affects cell behavior.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
Xun Xiong, Qinglei Zeng, Yonghuan Wang, Ying Li
Summary: In this work, the authors investigate the possibility of enhancing the resistance to crack growth in brittle materials through microstructure design. They establish a computational framework to simulate crack propagation and characterize fracture energy. The effects of different types of voids on toughening mechanisms are explored, and the critical conditions for embrittlement-toughening transition are identified. The study also discusses the difference between void toughening in brittle and ductile materials, and extends the toughening strategy to nacre-like materials.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
Huan Wang, Yong-Quan Liu, Jiu-Tao Hang, Guang-Kui Xu, Xi-Qiao Feng
Summary: This study establishes a cytoarchitectural model to accurately capture the buckling and postbuckling behaviors of epithelia under fast compression. The stress evolution of epithelia is divided into three stages: loading, phase transition, and stress recovery. The postbuckling process is governed by the active tension generated by the actomyosin network. The study also proposes a minimal model that predicts the flattening time and stress recovery extent as functions of applied strain or strain rate, in agreement with simulations and experiments.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
Lei Liu, Hao Liu, Yuming He, Dabiao Liu
Summary: This study investigates the mechanics and topologically complex morphologies of twisted rubber filaments using a combination of experiment and finite strain theory. A finite strain theory for hyperelastic filaments under combined tension, bending, and torsion has been established, and an experimental and theoretical morphological phase diagram has been constructed. The results accurately determine the configuration and critical points of phase transitions, and the theoretical predictions agree closely with the measurements.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
Abhishek Painuly, Kunnath Ranjith, Avinash Gupta
Summary: This paper analyzes the interfacial waves caused by frictional slipping and studies their dispersion relation and wave modes. By studying the slip waves in a geophysical model, the surface wave dispersion phenomenon is explored, and an alternative explanation is proposed.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
Houlin Xu, Joshua Vievering, Hoang T. Nguyen, Yupeng Zhang, Jia-Liang Le, Zdenek P. Bazant
Summary: Motivated by the extraordinary strength of nacre, this study investigated the probabilistic distribution of fishnet strength using Monte Carlo simulations and found that previous analytical solutions are not applicable for fishnets with a large number of links. By approximating large-scale fishnets as a continuum with cracks or holes, the study revealed that the strength distribution follows the Weibull distribution. This new model has significance for optimizing the strength-weight ratio in printed material structures.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
Souhayl Sadik, Arash Yavari
Summary: This paper revisits the mathematical foundations of nonlinear viscoelasticity and studies the geometry of viscoelastic deformations. It discusses the decomposition of the deformation gradient into elastic and viscous distortions and concludes that the viscous distortion can only be a two-point tensor. The governing equations of nonlinear viscoelasticity are derived and the constitutive and kinetic equations for various types of viscoelastic solids are discussed.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
Wen Cheng, Hongkuan Zhang, Yu Wei, Kun Wang, Gengkai Hu
Summary: In this study, we propose a phenomenon similar to Thouless pumping for a continuous in-plane elastic system, enabling topological transport of elastic waves through spatial modulation of material elasticity. By incorporating specific lattice microstructures, termed pentamode materials, precise and robust control over elastic wave propagation is achieved.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
Linda Werneck, Mertcan Han, Erdost Yildiz, Marc-Andre Keip, Metin Sitti, Michael Ortiz
Summary: We have developed a simple model that describes the ionic current through neuronal membranes by considering the membrane potential and extracellular ion concentration. The model combines a simplified Poisson-Nernst-Planck model of ion transport through individual ion channels with channel activation functions calibrated from experimental data. The calibrated model accounts for the transport of calcium, sodium, potassium, and chloride and shows remarkable agreement with experimentally measured current-voltage curves for human neural cells.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
