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Megathrusts at convergent plate boundaries generate the largest and some of the most hazardous earthquakes on Earth. However, their physical properties, including those influencing fault slip accumulation and release and earthquake‐related surface displacements, are still poorly constrained at critical depths. Here, we combine seismic imaging and geodetic modeling to investigate the structure and mechanical behavior of the Main Himalayan Thrust fault (MHT) in the center of the 2015 Mw 7.8 Gorkha rupture in Nepal. Our results from two independent observations consistently suggest the presence of a channel associated with the MHT with high compliance (shear modulus as low as ∼4 GPa) and strain anisotropy (stiffer in the vertical orientation than in the horizontal), likely arising from a weak subducting layer with north‐dipping foliation. Such mechanical heterogeneity significantly influences the quantification of short‐term fault kinematics and associated earthquake potential, with implications on across‐scale dynamics of plate boundaries in Himalaya and elsewhere. Plain Language Summary The Main Himalayan Thrust fault marks the boundary where the Indian continent slides beneath the Eurasian plate, causing earthquakes like the 2015 magnitude 7.8 event in Nepal. Subsurface images constructed using seismic waves suggest a weak layer surrounding the fault. However, we show that the seismic signature of this layer changes depending on the direction in which the seismic waves travel through it. We compare this information on the subsurface structure to insights from static surface motions during the earthquake. We find that the fit to the motion is poor when we assume the subsurface rock around the fault has the same strength in both horizontal and vertical orientations. The fit improves when we assume the near‐fault rock is stronger under vertical compression than under horizontal compression. This assumption also helps explain the images constructed using seismic waves. We suggest that a strong oriented rock fabric develops in a channel around the plate boundary. The presence of this fabric may have influenced our estimates of fault slip before, during and after great earthquakes. Accurately describing this behavior is crucial for understanding the earthquake potential of plate boundary faults. Key Points Seismic imaging suggests a Main Himalayan Thrust‐associated low‐velocity channel with north‐dipping anisotropic foliation Modeling of InSAR and GNSS data together suggests a weak channel with anisotropic rigidity whose orientation matches seismic constraints The weak anisotropic plate boundary may be related to S‐C fabrics and influence the margin geodynamics on different time scales

Finite Element simulations are a robust way of investigating cardiac biomechanics. To date, it has only been performed with the left ventricle (LV) alone for fetal hearts, even though results are likely different with biventricular (BiV) simulations. In this research, we conduct BiV simulations of the fetal heart based on 4D echocardiography images to show that it can capture the biomechanics of the normal healthy fetal heart, as well as those of fetal aortic stenosis better than the LV alone simulations. We found that performing LV alone simulations resulted in overestimation of LV stresses and pressures, compared to BiV simulations. Interestingly, inserting a compliance between the LV and right ventricle (RV) in the lumped parameter model of the LV only simulation effectively resolved these overestimations, demonstrating that the septum could be considered to play a LV-RV pressure communication role. However, stresses and strains spatial patterns remained altered from BiV simulations after the addition of the compliance. The BiV simulations corroborated previous studies in showing disease effects on the LV, where fetal aortic stenosis (AS) drastically elevated LV pressures and reduced strains and stroke volumes, which were moderated down with the addition of mitral regurgitation (MR). However, BiV simulations enabled an evaluation of the RV as well, where we observed that effects of the AS and MR on pressures and stroke volumes were generally much smaller and less consistent. The BiV simulations also enabled investigations of septal dynamics, which showed a rightward shift with AS, and partial restoration with MR. Interestingly, AS tended to enhance RV stroke volume, but MR moderated that down.

There is a great interest in improving mechanical testing of small samples produced in the laboratory. Plane strain compression is an effective test in which the workpiece is a thin sheet. This provides great potential for testing samples produced by high-pressure torsion. Thus, a custom tool was designed with the aim to test 10 mm diameter discs processed by this technique. Finite element analysis is used to evaluate the deformation zone, stress and strain distribution, and the accuracy in the estimation of stress–strain curves. Pure magnesium and a magnesium alloy processed by high-pressure torsion are tested using this custom-made tool. The trends observed in strength and ductility agree with trends reported in the literature for these materials.

This paper presents a numerical strategy to model box sections from bridge girders using horizontal layered shell finite elements. The basic idea is to avoid the construction of more computational expensive meshes based on the use of folded shell and brick finite elements. The numerical strategy imposes the deactivation of those layers related to empty spaces within the bridge cross-section. The performance of this technique is explored by means of two demanding practical applications related to bridge structures with constant and variable deck thicknesses. The first application deals with the static truck load test of the Caynarachi Bridge, located in Peru, and for which measured field data exists, while the second application is related to the construction stage analysis of a box bridge structure including time effects due to concrete creep, shrinkage and steel relaxation. The results demonstrate that the studied technique acceptably correlates with the measured field data,expressed in terms of vertical displacements,with correlation coefficients exceeding 0.94.Additionally, the outcomes align well with the results of other numerical techniques, allowing applicants to use this simplified modeling approach in daily design office.

This study focuses on calibrating the linear Drucker-Prager yield criterion for polypropylene under multiaxial loading conditions, using the Arcana fixture to achieve a wide range of triaxiality states. The Drucker-Prager criterion has been adapted for polymers, composites, and metals due to its ability to reflect the influence of hydrostatic pressure on yield stress. This study employs the Arcana fixture, which allows for testing flat plate samples under various angles, thereby simulating different stress states from pure shear to biaxial tension. Additionally, uniaxial compression tests were conducted to extend the range of triaxiality. The material used in this study is Sabic 83MF10, a polypropylene polymer. Samples were prepared by injection moulding and cut to specific dimensions. Tests were performed using a universal testing machine with the Arcana fixture, and the results were analysed to determine the yield strength, pressure, and triaxiality for each sample. The results showed a linear relationship between von Mises stress and hydrostatic pressure, with a friction angle (ß) of 20.65° and material cohesion (d) of 27.81. The numerical simulations in Abaqus confirmed the validity of the DruckerPrager model, accurately reflecting the moment of yielding for the tested samples.

The mechanism of the position-mode side guide in correcting slab centerline profile and camber in the roughing process of a hot strip mill (HSM) was analyzed using finite element simulation. The finite element model was established based on the actual size of the roughing mill and on the actual actuating time sequence of the roughing mill in China Steel Corporation (CSC), Kaohsiung. This work could be the first to give an insight into the mechanism of side guides in correcting the slab camber. Time sequence analysis was explored to visualize the progress of centerline profile variation and the interaction between the slab and the related roughing mill components at different moments. The history of reaction forces exerted on the slab was analyzed to explain the interaction between roughing mill components and the slab. The effect of the separation distance of side guide and the effect of the slab wedge on the centerline profile was investigated. A schematic model illustrating the reactions and the resulting moments exerted on the slab was created. By examining the force history, the cross-sectional strain/stress distribution, and the roll force across the horizontal roller, the correcting mechanism of the side guide could be elucidated. The simulation results provide further knowledge in selection and dimension design of side guide to improve the effectiveness of side guide in correcting the slab profile.

Besides the biology, stresses and strains within the tissue greatly influence the location of damage initiation and mode of failure in an intervertebral disk. Finite element models of a functional spinal unit (FSU) that incorporate reasonably accurate geometry and appropriate material properties are suitable to investigate such issues. Different material models and techniques have been used to model the anisotropic annulus fibrosus, but the abilities of these models to predict damage initiation in the annulus and to explain clinically observed phenomena are unclear. In this study, a hyperelastic anisotropic material model for the annulus with two different sets of material constants, experimentally determined using uniaxial and biaxial loading conditions, were incorporated in a 3D finite element model of a ligamentous FSU. The purpose of the study was to highlight the biomechanical differences (e.g., intradiscal pressure, motion, forces, stresses, strains, etc.) due to the dissimilarity between the two sets of material properties (uniaxial and biaxial). Based on the analyses, the biaxial constants simulations resulted in better agreements with the in vitro and in vivo data, and thus are more suitable for future damage analysis and failure prediction of the annulus under complex multiaxial loading conditions.

The impact velocity of particles during the cold spray process is crucial to the optimisation of coating quality and spraying costs. In the present investigation, both underexpanded and overexpanded impinging jets are employed to accelerate Aluminium particles towards a substrate. The impact velocity and angle statistics are generated by injecting polydisperse particles into the jet and the particle dynamics are characterised using the velocity and trajectories of the particles. The optimum particle size corresponding to the maximum impact speed is recast in terms of the Stokes number and shown to have a value of approximately one. Finally, a normal shock model is proposed which may be employed to estimate the particle impact speed using the nozzle exit conditions. It is shown that owing to artificial viscosity associated with the total variation diminishing scheme, this model tends to underestimate the speed.

The presented paper describes accurate distance measurement for a field-sensed magnetic suspension system. The proximity measurement is based on a Hall effect sensor. The proximity sensor is installed directly on the lower surface of the electro-magnet, which means that it is very sensitive to external magnetic influences and disturbances. External disturbances interfere with the information signal and reduce the usability and reliability of the proximity measurements and, consequently, the whole application operation. A sensor fusion algorithm is deployed for the aforementioned reasons. The sensor fusion algorithm is based on the Unscented Kalman Filter, where a nonlinear dynamic model was derived with the Finite Element Modelling approach. The advantage of such modelling is a more accurate dynamic model parameter estimation, especially in the case when the real structure, materials and dimensions of the real-time application are known. The novelty of the paper is the design of a compact electro-magnetic actuator with a built-in low cost proximity sensor for accurate proximity measurement of the magnetic object. The paper successively presents a modelling procedure with the finite element method, design and parameter settings of a sensor fusion algorithm with Unscented Kalman Filter and, finally, the implementation procedure and results of real-time operation.

Silicon/carbon (Si/C) composite anode materials have emerged as promising candidates for high‐energy‐density lithium‐ion batteries (LIBs), boasting advantages such as high capacity, cost‐effectiveness, and abundance. However, the integration of Si‐based materials into conventional graphite anodes introduces heterogeneous interactions between electrochemical and mechanical behaviors, owing to substantial volume changes and chemical potential variations. One significant consequence of these interactions is the impedance inhomogeneity, which adversely affects the discharging capacity of Si‐based LIBs. In an effort to comprehensively understand this phenomenon and its underlying mechanisms, an electrochemo‐mechanical‐coupled model is established, incorporating detailed particle geometries on the anode side. The model is employed to investigate polarization components and their evolution during the charging/discharging process. Various influencing factors, such as SiO weight percentage (wt%), electrode thickness, and SiO distributions (both in terms of distribution uniformity and direction), are systematically discussed. In this study, an efficient computational approach is offered to analyze battery polarizations, deepening the understanding of the inhomogeneous evolution of these polarizations in Si/C composite anodes. Ultimately, these insights guide the design of anodes for next‐generation high‐energy‐density LIBs. Silicon/carbon anode shows impedance inhomogeneity. An electrochemo‐mechanical‐coupled model is established, incorporating detailed particle geometries of anode. The model is employed to investigate polarization components and their evolution during the charging/discharging process. Various influencing factors, such as SiO weight percentage (wt%), are discussed. In this study, an efficient computational approach is offered to analyze battery polarizations, providing guidance of anode design.