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Orthodontic archwire rotation around its long axis, known as third-order torque, is utilised to correct tooth rotational misalignments moving the tooth root closer to or away from the cheek through engagement with an orthodontic bracket. Studying the behaviour of archwire and brackets during an applied rotation can aid in better understanding and appreciating the mechanics of third-order torque, potentially allowing for more effective orthodontic treatment protocols. Mechanically characterising archwire behaviour during third-order torque application is a complex task due to their physical scale and geometries. An advanced measurement technique was needed to address these constraints. A three-dimensional (3D) non-contact optical method using a digital image correlation (DIC) system was developed. An orthodontic torque simulator (OTS) was used to apply and measure third-order torque with 0.483 × 0.635 mm (0.019″ x 0.025″) rectangular archwires in tandem with a 3D DIC system, whereby surface deformations and strains could be computed using correlation algorithms. The 3D DIC system was implemented to enable third-order torque experimentation with the OTS while imaging the archwire and bracket surfaces. The 3D DIC system's ability to measure 3D archwire deformations and strains was verified using a finite element model, where comparisons between 3D DIC measurements and calculated results from the model were made to ensure the measurement capabilities of 3D DIC in the context of third-order torque. The 3D DIC system was then used to compare archwire behaviour between stainless steel (SS) and titanium molybdenum alloy (TMA) archwires to study potential clinical differences in archwire behaviour, in which the archwires were rotated with a custom SS rigid dowel (RD) as well as commercial Damon Q orthodontic brackets. The quantification of third-order torque and archwire deformations and strains led to the conclusion that SS archwires led to larger torque magnitudes compared to TMA archwires. The RD resulted in larger archwire strains compared to Damon Q brackets. The 3D DIC system provides a non-contact measurement technique that can further be used with third-order torque experimentation with the OTS. Image 1 • Isolated orthodontic archwire response to torsion is studied. • Finite element analysis is used to verify optical measurements. • Three-dimensional digital image correlation strain measurement method is validated. • Stainless steel and titanium molybdenum alloy archwire responses are compared. • Three-dimensional orthodontic archwire and bracket strain measurements are obtained. [ABSTRACT FROM AUTHOR]

Abstract: We present a model for the laminated composite plate problem based on the Reissner–Mindlin model and first-order lamination theory. The weak problem based on this model is solved with the finite element method using stabilized MITC (mixed interpolation of tensorial components) finite elements. Detailed a priori estimates are given for the mixed finite element formulation of the problem. Explicit bounds for the continuity and coercivity constants of the coupling terms are presented, thus refining earlier results. Furthermore, we present an application of the theory to the paper cockling problem and investigate the effect of boundary conditions on the small-scale deformation of the solution numerically. [Copyright &y& Elsevier]

Finite element analysis of the hip implant is conducted in this paper for representative femoral cross-section geometries and development of stress in the presence of bone cement is elucidated. Differences in cement stresses generated by varying implant cross-sections were compared with conventional features derived from representative implants. The analysis was performed under idealized implant assemblies by constraining the implant movement in the assembly. The cross-sections and implant geometries used are generic and intended to be representative of available geometries. This paper is a part of student research projects, prepared from a series of activities in biomedical implant research currently underway at Ohio Northern and Arkansas Tech Universities. [Copyright &y& Elsevier]

This paper summarizes the effective components of computer-aided design and computer-aided manufacturing (CAD-CAM) resin composites that contribute to achieving greater mechanical properties and further development. In silico multi-scale analysis, in silico nonlinear dynamic finite element analysis (FEA), and artificial intelligence (AI) were used to explore the effective components of CAD-CAM resin composites. The effects of the filler diameter and silane coupling ratio on the mechanical properties of CAD-CAM resin composites have been clarified through multi-scale analysis. The effects of the filler contents, and filler and monomer compositions have been investigated by AI algorithms. The fracture behavior of CAD-CAM composite crown was analyzed using in silico non-linear dynamic FEA. The longevity of CAD-CAM composite crown was assessed through step-stress accelerating life testing (SSALT). As the filler diameter decreases, there is an increase in elastic moduli and compressive strengths at the macroscale. At the nanoscale, a decrease in the filler diameter results in a decrease in the maximum value of the maximum principal strain. When the silane coupling ratio decreases, there is a decrease in the elastic modulus and compressive strength. According to the exhaustive search and feature importance analysis based on the AI algorithm, the combination of certain components was narrowed down to achieve a flexural strength of 269.5 MPa. The in silico non-linear FEA successfully detected the sign of the initial crack of the CAD-CAM composite molar crown. The SSALT revealed that CAD-CAM resin composite molar crowns containing nanofillers with a high fraction of resin matrix demonstrated great longevity. This paper summarized the effective components of CAD-CAM resin composites for their further development. The integration of in vitro and in silico approaches will expedite the advancement of CAD-CAM resin composites, offering benefits such as time efficiency and reduction of material waste for researchers and manufacturers. • The effective components of CAD-CAM resin composites (RC) have been summarized. • A smaller filler and a high silane coupling ratio enhance the mechanical properties of CAD-CAM RC. • Non-linear FEA has detected the sign of the initial crack in the CAD-CAM composite crown. • AI has been utilized to narrow down the effective components that achieve high flexural strength. • CAD-CAM composite crowns with a high fraction of resin matrix demonstrate remarkable longevity. [ABSTRACT FROM AUTHOR]

In order to solve the deficiencies of traditional board-level assembly CubeSat, such as low modularity, complex assembly process and poor scalability, a sandwich module assembly structure and method with no drive components is proposed, which can achieve quick connection and flexible assembly between modules. First, the proposed CubeSat standard module can be compatible with the standard interface of traditional CubeSat. The 4-in-1 interface of Mechanical-Electrical-Thermal-Data does not occupy the internal space of the standard module, and the electrical and thermal interfaces meet the requirements of CubeSat in-orbit work. Secondly, in order to improve the reliability of the connection between the modules, a plug-in connection scheme of the mechanical interface was designed. Finally, a genetic algorithm was used to optimize the interface size, so that it has better plug-in performance. The simulation results show that the performance of the male interface of titanium alloy material is the best, and the error between the finite element analysis and genetic algorithm results is less than 4.8 %, which is consistent with the actual tensile test results of the optimized prototype, and meets the mechanical requirements of the launch process and space orbit operation for CubeSat. The test results can guide production and provide a reference for subsequent engineering applications of CubeSat modular assembly. • In this paper, a standardized modular assembly method of CubeSat sandwich structure is designed. The assembly structure does not include driving parts, is simple in form, can be quickly connected, is flexible in assembly mode, and does not occupy the internal space of the standard module. • A standard 4-in-1 connection device was designed in this paper, including four interfaces: mechanical, electrical, thermal and data, which can achieve "plug and play". • This paper uses genetic algorithm to optimize the structure of the mechanical connection male joint, and obtains the optimal configuration of the male joint. This ensures the reliability, firmness and stability of mechanical connections, and meets the mechanical requirements of CubeSats during launch and in orbit. [ABSTRACT FROM AUTHOR]

Hydrogen storage vessels in hydrogen refueling stations are densely arranged, so high-speed fragments generated by explosion accidents may endanger adjacent vessels. It is of great significance to explore the dynamic responses and damage modes of hydrogen storage vessels under impact loads to promote the intrinsic safety development of hydrogen storage vessels. In this paper, a finite element analysis model is developed for simulating the dynamic responses of vessels under the impact of fragments. The influences of the number of winding layers, impact velocity, fragment mass, and fragment shape are investigated. The results show that fragment impact is a kind of local damage behavior with two typical stages of hitting and rebounding. The impact resistance of vessels increases with the number of winding layers. Impact velocity and fragment mass are positively related to deformation and damage. Conical fragments have stronger damage abilities, while spherical fragments cause greater deformation. [Display omitted] • The dynamic response and damage modes of vessels under impact were investigated. • The impact resistance of vessels increases with the number of winding layers. • Different factors have different effects on the damage and deformation of vessels. • System energy is mainly converted into internal energy. [ABSTRACT FROM AUTHOR]

Finite element (FE) analysis has emerged as the primary tool to investigate complex problems that are difficult to test clinically on living tissues, yielding valuable but not necessarily applicable information on orthodontic treatment modalities. Many studies are being published but the findings are difficult to interpret, lack in relevance, or cannot be critically appraised. In this paper, the FE modeling design and impact on the quality and outcome of research are discussed, with focus on how to narrow the gap between theory and clinical application. [ABSTRACT FROM AUTHOR]

In this paper, a novel equilibrium-based form-finding approach for a mega-latticed structure is presented based on vector-based 3D graphic statics and the Combinatorial Equilibrium Modelling (CEM). This approach can be effectively applied to the conceptual design phase of the structures with various design objectives under conservative loads. It allows us to adjust the design parameters in real time during the design phase and to obtain the resultant forms immediately. Based on a certain selection strategy, the forms have a better state of internal membrane forces compared to the original spherical structure. An ANSYS Parameter Design Language (APDL)-based automatic geometric modelling method for mega-latticed structures with various surface forms is developed. The proposed method solves the problem that the existing modelling methods are only available for spherical structures. It is highly applicable for modelling mega-latticed structures with spherical, cylindrical, and other heterogeneous surfaces. Furthermore, a complete design workflow that combines the proposed form-finding approach (for conceptual design), the automatic geometric modelling method (for transformation), and the finite element method (for deepening design and analysis), is discussed. This paper provides a reference for the design of mega-latticed structures and similar truss-based spatial structures. • A new equilibrium-based form-finding approach for a mega-latticed structure is proposed. • An automatic geometric modelling method for mega-latticed structures is improved. • A design workflow combining the form-finding approach and finite element method is discussed. • A case study is performed to verify the validity of the whole structural design process. [ABSTRACT FROM AUTHOR]

In zero-emission solutions for the hydrogen supply chain, high-pressure hydrogen storage in Type IV composite overwrapped pressure vessels (COPVs) is crucial for being safe and secure for a variety of stationary and transport applications. These COPVs consist of a polymeric liner material that works as a barrier for the stored hydrogen, while the carbon fiber-based composite provides the strength to hold the high-pressure hydrogen (of nominal working pressure more than 70 MPa to achieve the competitive driving range). Several experimental studies and simulation work have been performed on the viability of various polymers as low-permeability materials under low-pressure conditions. However, because of their proprietary nature and commercialized research, the characteristics of hydrogen permeation through polymers and their behavior at high pressure are still readily available in the literature. It is a major concern and the most crucial component of Type IV COPVs that these polymeric liners hold high pressure and maintain the necessary density of hydrogen (state of charge) toward operational requirements and safety concerns related to the cause of failures due to permeation (such as blistering, buckling, cracking, and so on). This paper investigates the role of polymeric liners on hydrogen permeation behavior using finite element modeling. For this, a UMATHT subroutine is developed within the Abaqus software to implement a new hydrogen permeation transport model with extended governing equations. Through the simulations and material modeling, the role of hydrogen transport properties (permeability, diffusivity, and solubility), structural characteristics (crystallinity, free volume, thickness) of plastic liners, and the role of operational parameters (concentration, pressure) are combined to validate the model from the experimental data in the literature to estimate the effective thickness required to maintain the permeation limit of the polymeric liner of 70 MPa Type IV COPVs. • A comprehensive review for polymeric materials is provided which are generally acts as liner material for high pressure hydrogen permeation barrier used in compressible high pressure hydrogen storage pressure vessels. • A mechanism of hydrogen permeation and exhaustive material model for polymeric liner material has been described to implement into Finite Element Analysis (FEA) using UMATHT a user subroutine. • Firstly, the investigation of material properties of HDPE polymer, geometry as representative volume element (RVE) of polymeric liner material of Type IV COPV for 2D sample with loading and boundary conditions described. • Then, the material model and all the FEA input implemented to validate the experimental published paper of Fujiwara et al. 2020, 2021 for HDPE material of thickness 1.5 mm and operating pressure up to 90 MPa. • The modeling framework of hydrogen permeation analysis considers the effect of pressure and concentration within the HDPE polymer sample with increasing thickness up to 5 mm that able to satisfy the permeation limit of hydrogen through the wall of 70 MPa Type IV composite pressure vessel (COPV). The hydrogen saturation inside the polymer has shown in terms of flux to evaluate the hydrogen transport properties through the polymeric liner material using time lag method. • The role of high-pressure cause compression of the HDPE polymer sample and corresponding crystallinity enhancement reported. • The results obtained from our study provide valuable insights into understanding the role of high-pressure hydrogen gas on the polymeric liner permeation behavior at various pressure. These insights can help determine their potential to model the complex behavior of hydrogen permeation modeling to evaluate the liner material permeation limit for 70 NWP of Type IV COPVs. [ABSTRACT FROM AUTHOR]

In recent years, there has been a notable increase in the utilization of multi-celled corrugated-plate CFST (MC-CFST) walls. In this paper, a connection joint between a steel beam and an MC-CFST wall was proposed. The joint consisted of MC-CFST walls, end columns, horizontal diaphragms, vertical plates, and steel beams, with each steel component being interconnected through welding. To investigate its mechanical properties, a refined finite element model was developed, and the accuracy of the modeling method was validated through existing test results. The stiffness and moment capacity of the joints were analyzed, focusing on the effects of various factors, including the insertion depth of the horizontal diaphragm, beam-to-column linear stiffness ratio, width-to-thickness ratio of the end column plate, diameter of the horizontal diaphragm opening, axial compression ratio, and concrete and steel strengths. Based on numerical and theoretical analyses, a calculation method for determining the moment capacity of the joint and establishing the lower limit value for the steel tube thickness of the end columns was proposed by using the yield line analysis. The predicted value of the moment capacity of the joint was found to deviate from the finite element result by no more than 10%, suggesting that the formula exhibited excellent accuracy and applicability. The minimum steel tube thickness of the end columns was determined by considering the yield of the beam flange section. The design method presented in this paper has the potential to offer a valuable reference for practical designs of the proposed connection joint. • A novel connection joint between a steel beam and a multi-celled corrugated-plate CFST wall was proposed. • A validated FE model was established for further investigation. • A parametric analysis was conducted to investigate the influence on the stiffness of the joints. • The effect of various parameters on the moment capacity of the joints was discussed. • Based on numerical and theoretical analyses, a formula for determining the moment capacity of the joint was proposed. [ABSTRACT FROM AUTHOR]

Abstract: Recently, in the pulp and paper industry, black liquor gasification (BLG) has been of interest as a potential replacement for the Tomlinson recovery boiler. Some commercial-scale BLG units have been developed. However, the full potential of high temperature gasifiers has not been realized because of the refractory failure. Computer simulation of existing materials will accelerate materials research in developing new refractory materials. A model based on continuum damage mechanics is presented to analyze the failure behavior of gasifier refractory lining under high temperature and chemical reactive environments by using the finite element method. This work provides a new methodology for the failure analysis of refractory material and would provide a powerful tool in the development of the high temperature gasifier refractories. [Copyright &y& Elsevier]

When partial and/or non-retentive preparation, such as those for occlusal veneers, is indicated, a proper and stable adhesion is essential. Therefore, the aim of this in vitro study was to evaluate the effect of loss of adhesion in different regions of the bonding interface on the fatigue behavior of simplified lithium disilicate restorations. For this, lithium disilicate (IPS e.max CAD) discs (1 mm thick and Ø = 10 mm) were fabricated, polished with #400-, #600-, #1200-grit silicon carbide (SiC) papers, and crystallized. As substrate, fiber-reinforced resin epoxy discs (2.5 mm thick and Ø = 10 mm) were fabricated and polished with #600-grit SiC paper. The ceramic bonding surface was treated with 5% hydrofluoric acid and a silane-containing primer (Monobond N), while the substrate was etched with 10% hydrofluoric acid followed by the application of the bonding system primers (Primer A + B). A lacquer (nail polish) was used to simulate the loss of adhesion in specific areas according to the study design to compose the testing groups: bonded (control; did not received nail polish application); – non-bonded (loss of adhesion in the whole specimen area); – margin (loss of adhesion in the ceramic margin); – center (loss of adhesion in the ceramic central area). The adhesive area of partially bonded groups was 50% of the adhesive surface. Then, the discs (n = 12) were bonded to the respective substrate using a resin cement (Multilink N), light-cured, water-stored for 90 days, and subjected to thermocycling (25,000 cycles, 5° to 55 °C) before testing. A cyclic fatigue test was run (20 Hz, initial load of 200 N for 5000 cycles, 50 N step size for 10,000 cycles each until specimen failure), and the fatigue failure load and number of cycles for failure were recorded. As complementary analysis, finite element analysis (FEA) and scanning electron microscopy analysis were performed. Kaplan-Meier log-rank (Mantel-Cox) was conducted for survival analysis. The results showed that as the loss of adhesion reaches the central area, the worse is the fatigue behavior and the higher is the stress peak concentration in the ceramic bonding surface. The bonded specimens presented better fatigue behavior and stress distribution compared to the others. In conclusion in a non-retentive preparation situation, proper adhesion is a must for the restoration fatigue behavior even after aging; while the loss of adhesion reaches central areas the mechanical functioning is compromised. • The fully bonded scenario promotes better fatigue behavior and stress distribution. • The loss of adhesion in restoration's central areas compromises the mechanical performance. • Stress peaks are higher in adhesion-loss scenarios, regardless of the debonded region. [ABSTRACT FROM AUTHOR]

• The first-ever systematic experimental program on the transverse tension tests of PGFRP profiles using non-standard short coupons was presented. • Size effects on transverse tensile properties in terms of coupon width and gauge length were examined. • Finite element models were developed to provide a better understanding of the failure mechanisms of the transverse short coupons under tension. • Recommended short coupon configuration for transverse tension tests of PGFRP profiles was eventually proposed. Pultruded glass fiber-reinforced polymer (PGFRP) profiles, manufactured via a pultrusion process, are increasingly used in civil engineering. However, due to the anisotropic nature, their transverse material properties are weaker than the longitudinal ones, necessitating robust material characterization methods for transverse properties. Commercially available PGFRP profiles often have insufficiently large cross-sections for standard-sized transverse tensile tests, prompting the need to investigate the effect of coupon size on transverse tensile properties and propose a feasible shorter coupon size. This paper therefore aims to examine the coupon-size effects and propose suitable short coupon geometries for transverse tensile tests. Standard material characterization tests were conducted on channel-section PGFRP profiles, followed by transverse tensile tests on six types of non-standard short coupons. The effects of coupon width and gauge length on transverse tensile properties were evaluated and compared across six aspects, with potential failure mechanisms further explored using finite element analysis (FEA). The paper concludes by proposing a feasible short coupon configuration for transverse tensile tests. [ABSTRACT FROM AUTHOR]

• Experimental tests of CFDSST columns is presented in detail in this paper. • Using ABAQUS, 3D finite element CFFSST column models under axial compression are developed. • The fundamental behaviour of the CFDSST columns is discussed in detail. • The feasibility of current design codes to design the CFDSST columns is evaluated. • The proposed design model is shown to predict well the strengths of CFDSST columns. This paper explores the performance of concrete-filled double-skin (square stiffened hollow sections (SHS) outer and circular hollow sections (CHS) inner) steel tubular (CFDSST) stub columns under axial compression through experimental research and finite element analysis. The static axial compression experiments of six concrete-filled stiffened steel tubular (CFST) stub columns and fifteen CFDSST stub columns were conducted. The test method, process, phenomena and results are introduced in detail. The results indicated that compared with conventional CFST stub columns, CFDSST stub columns with reasonable hollow ratio can maintain load-carrying capacity, increase ductility and reduce self-weight. Increasing the strength of concrete is the most effective way to increase the load-carrying capacities of specimens when other variables remain constant. Finite element (FE) software was then utilised to generate the models of current specimens. The simulation results showed reasonableness and accuracy compared to the experimental results. Based on the validated models, parameter analysis was performed to reveal the influence of concrete strength, width-to-thickness ratio of the outer steel tube, stiffener depth, hollow ratio and yield strength of the outer steel tube on the ultimate strengths of the specimens. In addition, compared with test and FE strengths, the ultimate strengths predicted by available international codes were found to be quite conservative. Consequently, a formula was proposed to predict the load-carrying capacity of CFDSST stub columns considering the effective cross-sectional areas of the outer steel tubes and the strength of the confined concrete. The formula has been shown to provide the best prediction with acceptable reliability. [ABSTRACT FROM AUTHOR]

• A vertically oriented double corrugated steel plate shear wall is proposed. • The elastic buckling behavior of the wall is affected by the bolt spacing. • The compressive and shear stability coefficients are established. • The stability of the wall affects the correlation curve of N/N u - V / V u. As a novel structural component, the Double Corrugated Steel Plate Shear Wall (DCSPSW) is formed by interlocking two corrugated steel plates using high-strength bolts. This paper investigates the global stability design methods for DCSPSWs under combined shear and compression loads. Firstly, this paper examines the elastic buckling performance of DCSPSWs under horizontal shear loads and vertical compression loads separately. A bolt spacing factor (η) is introduced to reflect the influence of bolt spacing on the elastic buckling stress of DCSPSWs. Then, based on extensive finite element analysis (FEA), this paper investigates the elastoplastic buckling behavior of DCSPSWs under shear loads and compression loads and establishes the corresponding stability curves to predict ultimate load-bearing capacity. It is found that the stability coefficients (φ s and φ c) are closely related to the normalized slenderness ratios (λ ns and λ nc). A smaller bolt spacing allows the DCSPSWs to exhibit improved elastic and elastoplastic stability. Finally, this study investigates the load-bearing performance of DCSPSWs under combined shear and compression loads and proposes the design formulas. The results show that the correlation curve of N / N u - V / V u can provide a conservative and accurate design. The research findings of this paper are advantageous for promoting the application of the innovative DCSPSWs. [Display omitted] [ABSTRACT FROM AUTHOR]

• Inclined stiffened panels of the fuselage tail were tested under shear load. • The simulation model was established to predict the buckling, post-buckling, and failure modes of inclined stiffened composite panels. • The non-linear relationship between the debonding of the stiffeners and the skin was quantitatively analyzed. • The concept of equivalent skin thickness was introduced to analyze the influence of stringer configuration on panel buckling and post-buckling. The purpose of this paper is to investigate the buckling and post-buckling behavior of inclined stiffened composite panels under shear load. Two types of stiffened composite panels were manufactured and tested. The buckling load, ultimate load and other required structural properties of the inclined stiffened composite panels were obtained. The test results show that the failure load of the two types of panels are 5.79 times and 11.2 times of the buckling load, respectively, indicating that such inclined stiffened panels have a large post-buckling capacity. The damage modes of the panel are tearing around the skin near the clamps and debonding of the stringers from the skin. The combination of Hashin failure criterion, Cohesive model and nonlinear connection of clamp was used to conduct finite element modeling, which effectively predicts the buckling, post-buckling and damage modes of the structure. The buckling and post-buckling behavior of stiffened panels with different stinger configurations were discussed based on finite element analysis. The results show that when the initial buckling occurs between the stringers, the buckling and failure load of the stiffened panel become larger as the equivalent skin thickness between the stringers become larger. The research in this paper can provide reference for aircraft structural design. [ABSTRACT FROM AUTHOR]

This paper is concerned with the behaviour of square concrete-filled dual-stiffened steel tubular (CFDSST) slender columns with a concentrically-placed inner circular steel tube. Previous studies have illustrated that these columns have greater structural performance in terms of load-carrying capacity compared with conventional concrete-filled stiffened steel tubular (CFSST) columns. However, the behaviour of CFDSST slender columns filled with ultra-high strength concrete (UHSC) has not been investigated and current design codes do not include provisions for UHSC, although it is increasingly popular owing to demands for structures to be lighter and more sustainable. Accordingly, the current paper fills that gap in existing knowledge and explores the behaviour of CFDSST slender columns using finite element (FE) analysis. The available test results from previous studies were collated and are employed to validate the numerical model. The validated FE model is then employed to investigate the axial load versus deflection responses for a wide variety of UHS-CFDSST slender columns. The behaviour of both intermediate-length and long columns is assessed through parametric analyses. The results of these studies show that the strength of the concrete sandwiched between the two steel sections, the yield strength of outer steel tube, and the outer tube slenderness ratio have a significant effect on the axial resistance of UHS-CFDSST intermediate-length columns, while the capacity of long columns is most affected by the sandwiched concrete strength. The ultimate resistances are compared with different available design methods, and AISC 360–16 code is recommended for predicting the ultimate resistance of UHS-CFDSST slender columns with modifications proposed to account for the different components forming this innovative cross-section. • New research is presented on the behaviour of square concrete-filled dual-stiffened steel tubular (CFDSST) slender columns. • Ultra high strength concrete is employed for the infill, for the first time. • An advanced finite element model is developed and validated. • The behaviour of intermediate-length and long columns is assessed by parametric analyses and reliable design is proposed. • The results show the potential of these sections to offer innovative structural solution for heavily loaded scenarios. [ABSTRACT FROM AUTHOR]

• Variational framework for the strain-smoothed element method. • Convergence analysis of the strain-smoothed element method. • Unified view for finite element methods with strain smoothing. • Numerical experiments supporting theoretical results. This paper is devoted to a rigorous mathematical foundation for the convergence properties of the strain-smoothed element (SSE) method. The SSE method has demonstrated improved convergence behaviors compared to other strain smoothing methods through various numerical examples; however, there has been no theoretical evidence for the convergence behavior. A unique feature of the SSE method is the construction of smoothed strain fields within elements by fully unifying the strains of adjacent elements. Owing to this feature, convergence analysis is required, which is different from other existing strain smoothing methods. In this paper, we first propose a novel mixed variational principle wherein the SSE method can be interpreted as a Galerkin approximation of that. The proposed variational principle is a generalization of the well-known Hu–Washizu variational principle; thus, various existing strain smoothing methods can be expressed in terms of the proposed variational principle. With a unified view of the SSE method and other existing methods through the proposed variational principle, we analyze the convergence behavior of the SSE method and explain the reason for the improved performance compared to other methods. We also present numerical experiments that support our theoretical results. [ABSTRACT FROM AUTHOR]

Recently, generation of electrical power from the oceanic wave draws incredible attention to the researchers and engineers. Although, oceanic wave energy is gigantic and available to most of the earth's surface, it is still unused because of the lack of technological excellence in the past decades. Therefore, research gap is created in this regard specially extraction of electrical power from the oceanic wave. In this paper, wave energy devices and optimization of the linear electrical generator (LEG) that mainly converts the mechanical energy (from the device) into electricity are presented in detail with finite element analysis (FEA). The methodology involves analysis of the design, observation of its electrical and magnetic properties, optimization, different copper windings, enhancement of output power, maximizing the efficiency of the LEG, and power density. To test the proposed method, an LEG is designed using the computer aided design software. Its geometry is then imported to ANSYS software for conducting FEA. The generated power, electrical, and magnetic properties of the LEG are observed for various conditions. Optimization procedure is parallelly conducted with FEA to ensure extracting the maximum output power and efficiency. Various magnetic materials are analyzed for selecting proper magnetic core and the permanent magnet to further increase the output power. Simulation results show that because of applying the proposed design method to the LEG with optimization, approximately 93.9% efficiency and 530 kW/m3 power density are achieved for 2 m/s velocity of the translator, which is the highest among almost all other existing LEGs so far. • Analysis of linear electrical generator (LEG) by finite element method (FEM) • Design and optimization of the LEG by FEM in stepwise manner with a flow chart • Selection of suitable copper winding and magnetic material to enhance output power • Reduction of core loss with applying advanced ferromagnetic core • Maximization of its efficiency by observing the electrical and magnetic properties [ABSTRACT FROM AUTHOR]

• This paper applied the lightweight aggregate concrete (LWAC) into partially encased steel-concrete composite (PEC) stub columns. • The axial compression test was conducted to explore the work properties of partially encased steel-concrete composite stub columns with LWAC. • The finite element models of the PEC-LC column were established to conduct a systemic parametric investigation. • The axial strength calculation method of PEC-LC columns was proposed considering the flange strength reduction and core concrete enhancement. This paper applied lightweight aggregate concrete (LWAC) in the partially encased steel-concrete composite (PEC) stub columns to achieve the advantages of lightweight and easy assembly. A total of 8 axial-loaded specimens were tested to explore the effect of concrete type, concrete strength, link spacing, longitudinal rebars, and height-to-width ratio on the compressive behavior of the partially encased steel-concrete composite stub columns with lightweight aggregate concrete (PEC-LC). Then, the finite element models of PEC-LC columns were established to conduct a systemic parametric investigation. The results demonstrated that the PEC-LC column experienced failure due to concrete crushing and local buckling of flanges, similar to the PEC column. Compared to the PEC column, the PEC-LC column exhibited a similar load-bearing capacity but poorer post-peak compressive performance, which could be improved by closer link spacing. Consequently, applying LWAC to reduce the self-weight of prefabricated members is a feasible option. Besides, the contact stress and the stress distribution at typical cross-sections were analyzed to reveal the confinement effect of H-shaped steel and links on the filled LWAC. Finally, A calculation method for estimating the axial compression capacity of the PEC-LC column was proposed, taking into account the reduction in flange strength and enhancement of core concrete. The accuracy of the calculation method was verified by comparison with experimental and numerical data. Overall, this research serves as a valuable reference for promoting the adoption of the PEC-LC column in assembled structures. [ABSTRACT FROM AUTHOR]

This paper addresses the problem of ranking correlated random variables according to relative importance. The importance of a variable derives from its influence on the variability of the response from a model. Applications include any input–output model for which response derivatives are available from each response analysis. Structural analysis models, i.e., finite element models, represent the specific motivation for this paper. The response derivatives are collected in a vector and transformed into a standardized parameter space. Points along that vector are transformed back to the original parameter space and utilized for the purpose of model insights and parameter ranking. Comparisons are made with the first-order Sobol sensitivity index, which requires sampling instead of the proposed single-analysis approach. Results suggest that the proposed importance measure matches the first-order Sobol index in many situations. However, for pure multiplicative "interaction" models, the first-order Sobol index tends to be anchored at the zero-correlation case. In contrast, the proposed measures are sensitive to correlation and the effect of correlation can be significant. [ABSTRACT FROM AUTHOR]

The propulsive characteristics of an Electric Solar Wind Sail are usually evaluated using a simplified model in which all the sail tethers are coplanar and form a sort of rigid disk. However, the three-dimensional arrangement of the tethers is fundamental information in the study of the spacecraft performance, and must be accounted for in refined mission analyses. In this paper, a Finite Element approach is chosen to estimate the deflected shape of the tethers, thus allowing important information on the structural response of the sail to be obtained. A parametric code is developed to perform a static analysis of an Electric Solar Wind Sail, whose requirements are given in terms of payload mass and spacecraft characteristic acceleration. In particular, the tether structural response is investigated using three different beam models, which are compared in terms of accuracy and computational efficiency. The analysis is specialized to the noteworthy case of a Sun-facing sail that is placed at a distance of one astronomical unit from the Sun. The numerical results, which concern a set of possible sail configurations, are compared with those taken from analytical models. • The paper analyzes the E-sail deformed shape using a finite element approach. • A parametric procedure is proposed to perform the E-sail static analysis. • The tether structural response is investigated using three different beam models. • The numerical results are compared with those taken from analytical models. [ABSTRACT FROM AUTHOR]

The companion paper Part I [ 1 ] deals with the experimental campaign of longitudinally stiffened plate girders subjected exclusively to patch loading. The current paper focuses on the numerical research and parametric study of the influence of patch load length and initial geometrical imperfections on the ultimate strength of longitudinally stiffened plate girders. In order to assess the patch load resistance, a geometrically and materially nonlinear finite element analysis has been performed. For a better verification with the experimental results, the finite element model includes the experimentally measured initial geometrical imperfections and material properties based on laboratory tests. The verification of the numerical model has been obtained through the comparison of the numerically and experimentally attained results for the ultimate loads and elastoplastic behavior of the girders. It has been shown that the numerical and experimental results are in perfect agreement, which enabled a fruitful background for parametric analysis, in which different initial geometrical imperfections have been used to ameliorate understandings about their influence on the ultimate strength under different patch load lengths. Conclusively, it may be stated that initial geometrical imperfections can play a decisive role, especially for longitudinally stiffened girders. Initial geometrical imperfections of stiffened girders that correspond to deformed shape at the collapse (collapse-affine imperfections), especially in the zone where the load is applied, will give the most unfavorable ultimate strengths. For the considered geometry in the present paper, the third buckling mode of longitudinally stiffened girders corresponds to the deformed shape and the lowest ultimate strengths are obtained. • Initial geometrical imperfections can play a decisive role for both longitudinally stiffened and unstiffened girders. • Unfavorable initial geometrical imperfections correspond to deformed shape at the collapse. • Increasing the patch load length increases the strengthening effect. • The strengthening effect is highly influenced by the shape of initial geometrical imperfections and patch load length. • The lowest patch load resistance of longitudinally stiffened girders is obtained for the third buckling mode. [ABSTRACT FROM AUTHOR]

[Display omitted] • Reactive forcefield molecular dynamics simulation used to evaluate mechanical performance of ABS/TPU fusion-bonded interface. • Interfacial adhesion responses obtained from MD simulation used in cohesive zone-based FEA model for macroscopic response evaluation. • FEA-based model shows good correlation with experimental data, signifying good predictive efficacy of simulation approach. • Comprehensive approach paves the way for atomistic engineering of molecular structures and efficient fine tuning of processing parameters. • Enables exploration of mechanisms and atomistic origins of interfacial damage at the fused bond line. This paper implements reactive forcefield molecular dynamics (MD) simulation to evaluate the mechanical performance of the fusion bond line formed between acrylonitrile butadiene styrene (ABS), and thermoplastic polyurethane (TPU). The simulated interfacial adhesion responses, as obtained from MD simulation, are further implemented as the interfacial properties between ABS and TPU in an upscaled cohesive zone-based finite element analysis (FEA) model for macroscopic response evaluation. Such upscaling enables fair comparison of the simulated macroscopic stress–strain response with experimental results obtained for 3D printed ABS/TPU hybrid samples with a fusion-bonded interface. Overall, the stress–strain response predicted from a FEA-based model shows a good correlation with the experimental data signifying good predictive efficacy of the simulation approach. Thus, by interactively linking the molecular structures of the polymers and the processing parameters with the macroscale interfacial adhesion response of the fusion bond line, the experimentally validated comprehensive approach presented in this paper paves the way for atomistic engineering of the molecular structures as well as efficient fine tuning of processing parameters to meet desired macro-scale performance needs besides enabling exploration of the mechanisms and atomistic origins of the interfacial damage at the fused bond line. [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate the impact resistance and energy dissipation capacity of a new type of multi-cell sandwich aluminum alloy plate filled with aluminum foam, in comparison to the single-cell structure. To achieve this goal, 30 sandwich aluminum alloy plates were tested using a drop hammer test machine, varying impact velocity, wall thickness, and the number of internal diaphragms. The results were analyzed and finite element analysis was conducted to explore the energy dissipation mechanisms and the effect of aluminum foam on multi-cell plates. The findings revealed three failure modes and three stages of the impact force time history curve. Multi-cell plate exhibited showed much better specific energy absorption compared with the single-cell plate. Taking an example displacement of 22.5 mm, which differentiates the specific energy absorption the most between the two types of structures, the multi-cell plate exhibited an average increase of 332% in specific energy absorption compared to the single-cell plate. The numerical simulations were consistent with experimental results and highlighted the contribution of different components to energy dissipation in both structures. • This paper presents a new type of multi-cell sandwich aluminum alloy plate filled with aluminum foam. • The experiments and FEA are carried out on single-cell and multi-cell sandwich aluminum alloy plates filled with aluminum foam. • The dynamic responses of single-cell and multi-cell plates under impact were obtained and analyzed. • The FEA was carried out to explore the energy dissipation mechanism of single-cell and multi-cell plates. [ABSTRACT FROM AUTHOR]

• Fully reproducible worked solution to computational WTST benchmark. • Illustration of automatable, geometrically scalable meshing protocol. • Illustration of prEN 1993-1-6-compliant GMNIA imperfection amplitude calibration. • Eigenmode and weld depression imperfections require different calibrations. • Benchmark makes start of public repository of GMNIA verification examples. An assessment of the elastic–plastic buckling limit state for multi-strake wind turbine support towers poses a particular challenge for the modern finite element analyst, who must competently navigate numerous modelling choices related to the tug-of-war between meshing and computational cost, the use of solvers that are robust to highly nonlinear behaviour, the potential for multiple near-simultaneously critical failure locations, the complex issue of imperfection sensitivity and finally the interpretation of the data into a safe and economic design. This paper presents a detailed reference solution to the computational buckling analysis of a standardised benchmark problem of an 8-MW multi-strake wind turbine support tower. Both linear and nonlinear analyses are performed, including advanced GMNIA with several different models of geometric imperfections. The crucial issue of interpreting the imperfection amplitude in a way that is compliant with the new prEN 1993-1-6 is discussed in detail. The solution presented herein is intended for use by analysts in both industry and academia for training, verification and calibration of finite element models and is intended to initiate a public repository of such computational solutions for metal civil engineering shell structures. This paper is the second of a pair. The first paper [37] presents a synthesis of 29 submissions to an international round-robin exercise performed on the same benchmark problem. [ABSTRACT FROM AUTHOR]

This paper takes the electric vehicle with HV battery traction which has achieved the "five-star" result of CNCAP as the research object, and uses HyperMesh and LS-DYNA to establish a lateral impact finite element model for simulation to verify the performance of this vehicle in C-IASI. In order to improve the performance of the side structure, the structure is optimized by upgrading the materials of key components, optimizing the key force transmission path and filling the cavity in the key deformation area with polymer structural stiffeners. According to the optimization scheme, the finite element model is established and calculated. The results show that the optimization scheme can effectively solve the problem of excessive intrusion and intrusion speed of the inner plate of the B-pillar in side impact, and improve the deformation mode of the B-pillar at the same time, improve the side impact safety performance of the vehicle, meet the requirements of "GOOD", and provide a reference for the solution of similar problems of subsequent related vehicles. [ABSTRACT FROM AUTHOR]

The main cause of failure in bonded ceramic restorations is material fracture due to excessive stress concentration at the base of the prosthesis. The design of restorative functionally graded materials (FGM) could represent a major advance in dissipating mechanical stresses during occlusal contacts. The aim of this paper is to carry out a complete factorial design of finite element analyses to optimize a multilayer FGM introduced at the bottom of an overlay prosthesis. The number and thickness of layers vary within a spectrum compatible with ceramic shaping processes whereas Young's moduli variations are set in the range of dental tissues. For a 1.5-mm thick prosthesis, the optimal FGM configuration appears to be a 5 layers of 0.2 mm thickness with a linear distribution of Young's modulus from 30 to 70 GPa. This configuration was implemented in a 3D model of a restored tooth with realistic geometry to validate the proof-of-concept. [ABSTRACT FROM AUTHOR]

Suspended sediment is a significant threat to the Great Barrier Reef (GBR) ecosystem. This catchment pollutant stems primarily from terrestrial soil erosion. Bulk masses of sediments have potential to propagate from river plumes into the mid-shelf and outer-shelf regions. Existing sediment forecasting methods suffer from the problem of low-resolution predictions, making them unsuitable for wide area coverage. In this paper, a novel sediment distribution prediction model is proposed to augment existing water quality management programs for the GBR. This model is based on the state-of-the-art Transformer network in conjunction with the well-known finite element analysis. For model training, the emerging physics-informed neural network is employed to incorporate both simulated and measured sediment data. Our proposed Finite Element Transformer (FE-Transformer) model offers accurate predictions of sediment across the entire GBR. It provides unblurred outputs, which cannot be achieved with previous next-frame prediction models. This paves a way for accurate forecasting of sediment, which in turn may lead to improved water quality management for the GBR. • Vision Transformer is proposed for next-frame prediction. • Finite element analysis is integrated with the Vision Transformer. • Sediment distribution in the GBR is forecasted using the proposed FE-Transformer. • PINN is employed to merge sediment PDE solutions with in-situ measured data. • The proposed model produces highly accurate unblurred output frames. [ABSTRACT FROM AUTHOR]

• Tests and finite element analysis on fire resistance of concrete filled steel double-tube and double-skin columns. • Parameter studies on fire resistance of concrete filled steel double-tube columns. • Structural response of concrete filled steel double-tube and double-skin columns in a fire condition. • Development of a new design model for calculating the fire resistance of concrete filled steel double-tube columns. Circular concrete-filled steel double-tube (CFSDT) columns have shown excellent ductility and load-carrying capacity. However, research on the fire resistance of CFSDT columns is still limited. This paper presents the fire tests, finite element (FE) modeling, behavior, and design of circular CFSDT columns and concrete-filled steel double-skin (CFSDS) columns exposed to fire. The fire resistance tests of one CFSDS and six CFSDT columns are described. Analysis is given on the effects of the material strength, the thickness of the inner steel tube, and the load ratio on the fire resistance of the specimens. Finite element models are developed that simulate the fire behavior of filled composite columns with double tubes and are verified by fire test results. The verified FE models are employed to undertake parametric studies on the structural responses of CFSDS and CFSDT columns under fire exposure. A design model is proposed for calculating the fire resistances of CFSDT columns. The results show that the load ratio and the column slenderness ratio have the most significant effect on the fire resistance of CFSDT columns; the cross-sectional parameters remarkably affect the fire resistance; and the material strength has a moderate impact on the fire resistance of CFSDT columns. Compared with CFSDS specimens, the existence of the core concrete significantly increases the fire resistance of CFSDT columns. The proposed design model for fire resistance can yield a safe prediction. [ABSTRACT FROM AUTHOR]

In previous research on shear panel dampers (SPDs), the assumption that the damper only experiences in-plane loading has been predominant, neglecting the effects of bidirectional loading. This paper aims to provide a comprehensive understanding of the mechanical behavior of SPDs under bidirectional loading. Cyclic quasi-static tests and numerical simulations were conducted on both unstiffened and stiffened SPDs loaded in the in-plane direction and at a 45-degree angle, representing unidirectional and bidirectional loading, respectively. The results demonstrate distinct differences in failure mode, yielding, and stress distribution of SPD under bidirectional loading. To further investigate the influence of different loading angles on the mechanical properties of SPD, parametric studies were conducted. The findings reveal that the in-plane yield force of SPD gradually decreases as the loading angle increases, which raises the concern on the potentially overestimated the performance of bidirectional loaded SPD in the in-plane direction during structural design. • Mechanical behavior of shear panel damper under bidirectional loading was studied. • The stiffeners' impact on SPD in unidirectional and bidirectional cases was studied. • Effect of loading angles on the mechanical properties of SPD was studied. [ABSTRACT FROM AUTHOR]

• Shear bands' morphology in amorphous polymer under four-point bending is concerned. • Physical mechanisms of detour and strength decay of bands at intersections are analyzed. • Constitutive model can predict the morphology of shear bands under four-point bending. As a significant means of plastic deformation in polymers, shear bands play a crucial role in material failure and performance optimization. In this paper, the finite element method is utilized to numerically investigate the morphology of shear bands in an amorphous polymer plate under plane strain four-point bending. Amorphous polymers are characterized by the elastic-viscoplastic constitutive relationship that takes into account the effect of pressure on yielding, including intrinsic softening and subsequent orientation hardening. The impact of material parameters including intrinsic softening, orientation hardening, and initial imperfections on the evolution of shear bands and the undulations of the specimen's surface are explored in detail. In addition, the physical mechanisms responsible for the detour and strength decay of shear bands after passing the intersections are described. It appears that intrinsic softening is the driving force promoting the detour of shear bands at intersections, while orientation hardening is the driving force inhibiting the detour. By comparing the simulations with experimental observations, it is demonstrated that the model can qualitatively depict the morphology of the shear band during the four-point bending of amorphous glassy polymers. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper investigates the role of basement depth on the response of framed buildings to tunnel construction in sandy soil using finite element modelling. Six frames are considered to explore the influences of tunnel cover depth, building width, eccentricity, and the number of storeys on the role of basement depth. The numerical models adopt the hypoplastic constitute model to simulate the behaviour of the sand. The results suggest that basement depth plays an important role in determining the settlements of the raft foundations and soil displacements due to tunnelling. Its effect on the structural shear distortion primarily depends on the ratio of tunnel depth to building width (C / B); an increase in basement depth decreases and increases building maximum shear distortion for C / B < 0.3 and for C / B > 0.35, respectively. The basement considerably increases the shear distortion of short eccentric structures by preventing tilt of the building, causing a divergence from existing empirical envelopes and modification factors for shear distortion. The applicability of the meta-model is extended to the embedded structures by linking the building tilt freedom coefficient with the basement depth parameter, achieving good agreement between the predicted results and calculated data. Limitations and practical implications of the research are briefly discussed. [ABSTRACT FROM AUTHOR]

This paper describes an innovative method which automatically calculates the material properties and boundary conditions which must be applied to an axisymmetric Finite Element (FE) model of a quasi-axisymmetric component, to account for the fact that some regions in a quasi-axisymmetric model are not fully axisymmetric. The automated process has been implemented using the Application Programming Interface (API) of a commercial FE package and builds on an existing process which automatically creates an axisymmetric FE mesh from a 3D CAD model of a quasi-axisymmetric component. The method is demonstrated for a series of component models. For the thermal analysis of an aerospace turbine rear structure model, the FE model was created from the 3D CAD model in approximately 2 min and gave nodal temperatures within 9% of a 3D FE model. • Allows the use of an axisymmetric analysis for quasi-axisymmetric components. • Automatic calculation of shape coefficients. • Shape coefficients account for the non-axisymmetric features of the component. • Modifies material properties and boundary conditions using shape coefficients. • Accurate results in reduced computational time compared to a 3D FE model. [ABSTRACT FROM AUTHOR]

Prestressing is a viable and effective technique used in concrete structures that allows the improvement of their performance. Its efficiency depends on the layout of the tendons, understood as the number of strands, their profile, curvature, and eccentricities. Layout design is a laborious and usually iterative trial-and-error process that aims to ensure that stress limits are not exceeded while, on the other hand, to minimize the total weight of prestressing steel. To automate the process, this research presents a novel genetic algorithm and a machine learning-based approach with a parametrically defined geometry of a tendon consisting of straight lines and circular arcs. The paper describes assumptions, implementation, and validation of the methods using a two-span two-girder bridge structure as an example. The genetic algorithm was incorporated to minimize the total weight of prestressing steel and ensure a correct design with no limit state exceedances. Since prestress evaluation in statically indeterminate structures requires repetitive and time-consuming numerical simulations, usually finite element analysis (FEA), a neural network was used to predict numerical output based on the layout parameters. The introduction of the neural network significantly reduced the total computation time. The results show the usability of the proposed approach in further studies and in engineering practice. • Genetic algorithm and neural network combined establish an effective optimization framework for prestressed concrete design. • Genetic algorithm is able to find optimal solutions even when all candidates in initial generations exceed the constraints. • Neural network can successfully replace time-consuming Finite Element Analysis (FEA) in design process. • The profile geometry of a tendon can be easily parametrized using linear segments and circular arcs. [ABSTRACT FROM AUTHOR]

Non-directional rafting of γ' phases in high generation nickel-based single crystal superalloys happens when the alloys are thermally exposed at high temperatures, but so far the reason remains unclear. The microstructures and internal stress fields of a 4th generation single crystal superalloy during thermal exposure at 1100 ℃ and 950 ℃ are investigated using transmission electron microscopy and finite element analysis. It is found that the non-directional rafting of γ' phases occurs after 1100 ℃/200 h and 950 ℃/500 h thermal exposures. The γ' phases are mainly rodlike shape in the space after thermal exposures and a small quantity of γ' rafts exist as well. The elastic strain energy gradient in γ matrix caused by the inhomogeneity of matrix channel width in the alloy is most likely the driving force for the non-directional rafting. Additionally, dislocations are observed only after the thermal exposure process at 1100 ℃. The effect of dislocations on non-directional rafting during thermal exposure is discussed in detail in the paper. • TEM and finite element analysis are used to study non-directional rafting of γ'. • γ' phases are mainly rodlike spatially after thermal exposure at high temperature. • It is found that dislocations are unnecessary for the non-directional rafting. • Elastic strain energy is larger in narrower γ matrix channel at high temperature. • Elastic strain energy gradient in matrix probably causes non-directional rafting. [ABSTRACT FROM AUTHOR]

Unicompartmental knee arthroplasty is an effective treatment for knee osteoarthritis, but it has the risk of failure, and the installation position of the prosthesis is one of the factors affecting the failure. There are few biomechanical studies on the installation angle of unicompartmental knee prosthesis. Constructed a finite element model of a normal human knee joint, and the validity of the model was verified by stress and front anterior methods. The mobile-bearing unicompartmental knee arthroplasty femoral prosthesis was placed at 3° intervals from 0° sagittal plane to 15° flexion, and − 2° and 17°were established, and observing the biomechanical changes of components. Maximum peak stresses occurred at a sagittal mounting angle of −2° for the insert and the contralateral meniscus, with the tibia showing a maximum at 17° sagittal and the tibial prosthesis stress maximum occurring at 6° sagittal. As the sagittal plane angle of the femoral prosthesis increases and the osteotomy distance extends posteriorly, more bone is amputated during the osteotomy. The ratio of the distance from the tip of the anterior intramedullary nail to the anterior end of the osteotomy to the total anteroposterior length of the sagittal osteotomy ranged from 43.2% to 44.6%. In this paper, the more appropriate sagittal mounting position for the femoral prosthesis is between 9 and 12°, based on the amount of osteotomy and the peak stress of each component in a standing position. • Material assignment to the skeletal model based on the grey scale • Biomechanical effects of sagittal angles of femoral prostheses • Recommended femoral prosthesis angles in terms of Mises stresses and osteotomies • Anterior intramedullary nail and anterior end of the femoral osteotomy distance [ABSTRACT FROM AUTHOR]

• An original ICVI algorithm reproducing the pyrolytic carbon deposition process is proposed. • The relationship between the process parameters and mechanical properties of unidirectional carbon/carbon composites is investigated. • The transverse modulus and tensile strength increase with an increase of the infiltration time, pressure, and temperature. • Interfacial debonding and propagation of multiple cracks result in the complete failure of unidirectional carbon/carbon composites. This paper proposes an innovative algorithm derived from the isothermal chemical infiltration process to generate quasi-real microstructures of unidirectional carbon/carbon composites. This algorithm, which can predict the relationship between the composite density and infiltration time, is termed the isothermal chemical infiltration algorithm. To further evaluate the relationship between the process parameters and the mechanical properties, a mesoscale finite element model of the unidirectional carbon/carbon composite is established based on the isothermal chemical infiltration algorithm. After validation, the developed numerical model is employed to study the effects of the infiltration time, pressure, and temperature on the effective mechanical properties. The results show that the transverse modulus and tensile strength increase with an increase in the infiltration time, pressure, and temperature, with the effect of temperature being the most significant. In parallel, it is revealed that the complete failure of unidirectional carbon/carbon composites results from interfacial debonding and propagation of multiple cracks during transverse tension. The proposed model has potential applications in the process design and optimization of high-performance carbon/carbon composites. [Display omitted] [ABSTRACT FROM AUTHOR]

With the proliferation of large-span structures and super high-rise building structures, further requirements have been placed on the bearing capacity and mechanical performance of special-shaped concrete-filled steel tubular (CFST) columns. In an effort to improve the performance of traditional T-shaped CFST columns, a series of axial compression experiments and numerical simulations were conducted on eight middle-long T-shaped CFST columns with embedded T-shaped steel skeleton, with the studied parameters covering diverse T-shaped steel tube confinement index (θ), embedded T-shaped steel skeleton ratio (ρ) and slenderness ratio (λ). The investigation contents include analysis of failure modes, load-mid span deflection curves, load-longitudinal and transverse strain curves, load-average longitudinal curves and parameter analysis. The experimental failure modes for all columns are a combination of local buckling and overall bending. Results demonstrate that the ultimate bearing capacity (N u) of the columns increases with higher values of θ and ρ while decreases with higher values of λ. As λ increases, the global bending failure of the column becomes increasingly pronounced. Furthermore, finite element analysis (FEA) models were built to simulate the axial compression mechanical performance of middle-long T-shaped CFST columns with embedded T-shaped steel skeleton. The simulation results were then compared with experimental results to validate the feasibility of the FEA models. Finally, simplified calculation formulae for estimating the ultimate load-bearing capacity of middle-long columns were suggested. The calculation results are indicative of notable agreement with the experimental results. • The paper presents an experimental study on T-shaped CFST columns with embedded T-shaped steel skeleton. • The composite columns shows excellent load-bearing capacity, ductility and deformation ability. • T-shaped steel skeleton improves the strength and the ductility capacity of composite columns • A finite element analysis for composite columns is developed. • A simplified calculation formula for composite columns is developed. [ABSTRACT FROM AUTHOR]

Shear walls are widely used as lateral load-resisting systems in high-rise building structures. The design and nonlinear analysis of shear walls under seismic loads for recoverability are complicated and challenging, which demands nonlinear computer modeling procedures. This paper presents a novel finite element named Double Vertical Beam-column with Shell Element (DVBSE) for the nonlinear analysis of complex reinforced concrete shear walls with columns. The DVBSE is implemented in the open-source finite element program OpenSees. The theoretical formulations of DVBSE are described in detail. The accuracy of the developed DVBSE is established by comparing the finite element analysis results with existing experimental data on recoverable steel-GFRP composite bar reinforced concrete shear walls. The comparative study demonstrates that the proposed DVBSE is superior to the commonly used finite element model in simulating the responses of recoverable complex shear walls under seismic loads. These research findings contribute to further advancements in the development of new shear wall elements and lay a solid foundation for the nonlinear numerical simulation of innovative shear walls. • A new finite element DVBSE is developed for modeling shear walls under seismic loads. • The DVBSE incorporates vertical fiber-based beam-column elements and shell elements. • The DVBSE is implemented in the open-source finite element program OpenSees. • The accuracy of the DVBSE is verified by test results of recoverable complex shear walls. • The DVBSE offers an efficient approach to simulate the seismic behavior of shear walls. [ABSTRACT FROM AUTHOR]

• Quantified the effect of Hill anisotropic plasticity on J-Q characterization of semi-circular surface cracks. • Demonstrated that the isotropic and anisotropic J – Q parameters can significantly diverge, especially, when crack planes are misaligned with respect to the material coordinate system. • The results are important for providing accurate predictions of failure in pipeline steels that often show significant plastic anisoptropy. In this paper, the J - Q two-parameter characterization of Hill-anisotropic elastic–plastic crack-front fields are examined for surface cracked plates under uniaxial tensile loadings. A method for two-parameter characterization crack-front field in anisotropic plastic materials is presented. Extensive three-dimensional elastic–plastic finite element analyses were performed for semi-circular surface cracks in a finite thickness plate, under remote uniaxial tension loading conditions. Surface cracks with relative depths a / t = 0.2, 0.6 were investigated. The loading levels spanned from small-scale to large-scale yielding. Different crack orientations with respect to the material coordinate directions were also considered. In topological planes perpendicular to the crack front, the crack-front stress fields were obtained. In order to facilitate the determination of Q -factors, modified boundary layer analyses were also conducted. The modified boundary layer analyses were adapted to account for plastic anisotropy. The J - Q two-parameter approach was then used in characterizing the elastic–plastic crack-front stress fields along these 3D crack fronts. Complete distributions of the J -integral and Q -factors for a wide range of loading conditions were obtained. The results indicate that the J – Q characterization is applicable to Hill-anisotropic plastic materials and provides good estimate for the crack-front constraint loss experienced under large-scale yielding. It was also observed that the isotropic and anisotropic J – Q parameters can significantly diverge, especially, when crack planes are misaligned with respect to the material coordinate system. This highlights the importance of the consideration of plastic anisotropy when performing constraint-based fracture mechanics analyses. [ABSTRACT FROM AUTHOR]

To maintain the physiological dynamics of the mitral annulus, mitral annuloplasty rings (MAR) must be flexible. Enhanced flexibility implies decreased resistance to fatigue and potential for fatigue fracture. This study established new methods to test the flexible fatigue life of MAR in-vitro using numerical analysis; the purpose is that the fatigue test could reflect the real stress distribution in-vivo. Based on the conventional test methods (C1, D1), this paper presents a novel test method (C2, D2). Four testing methods for open-end annuloplasty rings (C1, C2) and closed-end annuloplasty rings (D1, D2) were modelled and their stress distribution calculated by finite element analysis. The mean absolute error (Χ) and the Pearson correlation coefficient (Φ) were used to quantify the difference in stress distribution between the loading modes in-vivo and in-vitro. For closed-end annuloplasty rings, the novel test method (D2) is not obvious better than conventional test methods(D1) in duplicating the stress distribution (Φ D1 = 0.88 vs Φ D2 = 0.92). However, the maximum values of stress in the novel test method are closer to the maximum value of stress under in-vivo loading (Χ D1 = 5.2Mpa vs Χ D2 = 4.4Mpa). For open-end annuloplasty rings, the novel test method(C2) is obviously superior to the conventional test method(C1) in duplicating both the stress distribution and the stress peak values of the in-vivo loading (Φ C1 = 0.22 vs Φ C2 = 0.98; Χ C1 = 59.1Mpa vs Χ C2 = 11.0Mpa). The in-vitro loading methods described in this article more closely approximated in-vivo conditions compared to traditional methods. They are simpler to operate, more efficient and can help manufacturers expedite new product development, assist regulatory agencies with product quality oversight. [ABSTRACT FROM AUTHOR]

Headed stud shear connectors are commonly implemented in steel-concrete composite floors for connecting the concrete slab to the steel beam and providing composite action between those two elements. The orientation of profiled sheeting is usually transverse or parallel to the supporting beam, and for those cases, design codes provide specific detailing requests and relations for obtaining headed stud resistance. Nevertheless, design codes do not recognise specific configurations when the angle between profiled sheeting ribs and the beam is in the range between 0° and 90°, which is characteristic of irregular-shaped floor structures. Due to the lack of design recommendations for headed stud resistance in these cases, investigations of the effect of the rib-to-beam angle on headed stud shear performance were conducted and presented in this paper. Experimental work included push-out tests conducted on specimens with rib-to-beam angles of 45° and 60°, as well as control specimens with ribs transverse to the beam. The influence of varied rib-to-beam angles on shear connector properties such as shear resistance, stiffness, ductility, and failure mode was discussed. According to experimental research, finite element models of push-out tests were created and verified. The parametric numerical analysis covered key parameters such as concrete class, headed stud height and diameter, and rib-to-beam angle. According to the results, an analytical relation for obtaining headed stud resistance in profiled steel sheeting with a rib-to-beam angle between 30° and 90° was proposed. • Rib-to-beam angles between 0° and 90° in steel-concrete composite beams. • Experimental push-out tests on headed studs with rib-to-beam angles of 45° and 60°. • Development of finite element numerical models. • Parametric study for different rib-to-beam angles, concrete classes and stud geometry. • Analytical relation for stud resistance for varied rib-to-beam angles. [ABSTRACT FROM AUTHOR]

In application scenarios such as astronautics, high-altitude aircraft, medical radiography, high-energy physics, and nuclear power plants, the irradiation resistance of electronic components is one of the basic requirements for their reliability. HfO 2 -based ferroelectric films have the advantages of high CMOS process compatibility, good miniaturizability, low operating voltage, and excellent irradiation resistance, which are the core materials for the new generation of irradiation resistance ferroelectric memories. In this paper, two kinds of metal-electrode ferroelectric capacitors, W/Hf 0.5 Zr 0.5 O 2 /W (WW) and Pt/Hf 0.5 Zr 0.5 O 2 /Pt (PP), have been prepared, and three gradient γ-irradiation experiments have been carried out on the two kinds of ferroelectric capacitors. The effect of metal electrodes on the irradiation resistance of Hf 0.5 Zr 0.5 O 2 ferroelectric thin films was carefully investigated by comparing and analyzing the statistical laws of polarization change and rectangularity change before and after irradiation of a large number of devices. The experimental results show that the WW devices have better irradiation resistance than PP devices, and we further explain the irradiation resistance mechanism by first-principle calculations and finite element analysis to verify the credibility of the experimental results. Finally, we conducted a comparative test of the fatigue and wake-up characteristics of the WW devices before and after irradiation, and the results show that the prepared W/Hf 0.5 Zr 0.5 O 2 /W devices can withstand very high total γ-dose radiation, reaching up to 13.86 Mrad(Si), and they are very suitable for the application of irradiation resistant electronics. [Display omitted] • The Hf 0.5 Zr 0.5 O 2 (HZO) thin films with outstanding ferroelectric properties were prepared. • The HZO ferroelectric thin films exhibited extremely high radiation tolerance (reaching up to 13.86 Mrad(Si)). • The effect of different metal electrodes on the irradiation resistance of HZO ferroelectric thin films was analyzed. [ABSTRACT FROM AUTHOR]

This paper outlines the findings derived from a study conducted within the LEAP-2022 project, focusing on analyzing the seismic response of a sheet-pile retaining structure that supports liquefiable soils. The primary objective is to assess the efficacy of two distinct constitutive models–Manzari-Dafalias (MD) and PM4Sand–following their calibration utilizing element tests conducted on Ottawa-F65 sand. By employing these calibrated models, finite element models are generated to emulate centrifuge experiments. The results indicate that both the MD and PM4Sand models adequately capture the behavior of liquefiable soils and consequent wall displacements. Furthermore, the study emphasizes the significance of accurately calibrating for cyclic stress demands at the wall's toe and the passive zone to precisely predict wall behavior. It also highlights that number of cycles has a significant effect on simulation results. • Wall behavior in liquefiable soils can successfully be simulated in liquefiable soils. • Initial Condition of toe of the wall should be considered in the tests used for calibration. • Simulation accuracy is dependent on loading cycles for PM4Sand and MD. • MD and PM4Sand models struggle predictions for elements tests with initial shear stress. [ABSTRACT FROM AUTHOR]

Engineered cementitious composites (ECCs) have excellent crack control capacity and pseudo-strain-hardening behaviour. They can be used to improve the damage-tolerant capacity of vulnerable parts of structures. To improve the seismic performance of a traditional prefabricated column connected with grouted sleeves (GSs), an innovative prefabricated ECC shell–reinforced concrete (RC) composite column with GSs (ECC–PRC–GSs) is proposed in this paper. Then, three-dimensional nonlinear finite element models of the ECC–PRC–GSs are established and validated with previous experimental results. Subsequently, parametric analysis of the ECC–PRC–GSs is systematically performed to assess the seismic performance of ECC–PRC–GSs. Notably, certain important design suggestions for the ECC–PRC–GSs are proposed. Finally, a theoretical model is developed to predict the flexural bearing capacity of ECC–PRC–GSs based on the strain compatibility and force equilibrium conditions. The effectiveness of the model is verified through finite element analysis and experimental results. • An innovative prefabricated engineered cementitious composite (ECC) shell–reinforced concrete (RC) composite column with grouted sleeves (ECC–PRC–GSs) is proposed. • Numerical and analytical study on the seismic performance of the ECC–PRC–GSs is conducted. • A theoretical model is developed to predict the flexural bearing capacity of the ECC–PRC–GSs. [ABSTRACT FROM AUTHOR]

In this paper, a composite column using carbon fibre reinforced plastics and polyvinyl chloride composite tube (CFRP-PVC) to constrain coral aggregate seawater sea-sand concrete (CSSC) was proposed, and CFRP was pasted on the inner and outer walls of the PVC tube. To investigate the effects of the number of CFRP layers and void defects on the axial compression performance of PVC tubes, six specimens were made for axial compression loading tests and finite element parameter analysis. The results indicate that due to PVC improving the integrity of CFRP, PVC tube provide a stress transfer path for CFRP, placing CSSC in a triaxial compression state. When both the inner and outer walls of the tube are pasted with CFRP, brittle failure of CFRP-PVC tube can be effectively avoided and have relatively superior mechanical properties. In the same situation, when one layer of CFRP is pasted on the inner wall of the tube, it has better ductility and bearing capacity. When two layers of CFRP are pasted on the outer wall of the tube, the coefficient of constraint stress increase is as high as 121.5%, and the void defect only has a significant impact on ductility. A finite element model of CFRP-PVC confined CSSC columns considering Hashin damage criterion was established based on ABAQUS, accurately predicting the failure process and CFRP damage morphology of test columns under axial load. Parameter analysis shows that when the confinement coefficient of CFRP-PVC confined CSSC columns is less than 0.3 and the height-diameter ratio is greater than 15, the load-displacement curve will lose the strengthening stage, and increasing the number of outer CFRP layers will slightly increase the stiffness of the strengthening stage. A bearing capacity calculation method suitable for CFRP-PVC confined CSSC was proposed based on the model of steel tube confined concrete, with an error of 1.2%. ● CFRP-PVC tube confined coral aggregate seawater sea-sand concrete (CSSC) column was proposed. ● The axial compression test was conducted to explore the mechanical properties of CFRP-PVC confined CSSC columns. ● The finite element models of the CFRP-PVC confined CSSC column were established to conduct parametric investigation. ● The axial strength calculation method of CFRP-PVC confined CSSC columns was proposed considering the CFRP-PVC tube restraint efficiency. [ABSTRACT FROM AUTHOR]

The use of cold-formed steel (CFS) built-up sections in engineering practice is widely gaining popularity due to their ability to provide sustainable solutions and optimised section design opportunities. This paper presents an experimental and numerical investigation conducted on CFS built-up stiffened box section columns under axial compression. A total of 13 new experimental tests were conducted with specimens having an overall web depth up to 550 mm. Detailed nonlinear elasto-plastic finite element (FE) models were then developed and verified against the test results. Upon verification, a parametric study involving 144 FE models was carried out to investigate the effects of section thickness, column length, and screw spacing on the buckling resistance of CFS built-up stiffened box sections. The test and finite element analysis (FEA) results were compared with the buckling resistances determined by the American Iron and Steel Institute (AISI S100) and Australian and New Zealand Standards (AS/NZS 4600). It was found that the buckling resistances determined by the AISI S100 and AS/NZS 4600 for CFS built-up stiffened box sections were conservative by 9.3% on average, compared to experimental and FEA results. Modified Direct Strength Method (DSM) design equations for predicting the buckling resistances of CFS built-up stiffened box sections were then proposed, and a reliability analysis was conducted to assess the feasibility of the proposed equations. • Buckling resistance of axially loaded CFS built-up stiffened box sections was studied experimentally and numerically. • A nonlinear finite element model was developed and validated against the test results. • A parametric study was conducted to investigate the effects of different parameters. • Assessment of the current design guidelines was conducted. • New design equations for predicting the buckling resistance were proposed. [ABSTRACT FROM AUTHOR]

A high-pressure chamber is the main equipment required for simulating deep-sea operational environment and used for evaluating the performances of underwater equipment such as underwater vehicles under a preset pressure so that the possible malfunctions could be alarmed before deep-sea commissioning. In this paper, due to its current unavailability, a high-pressure chamber with the maximum working pressure of 60 MPa was designed, which has the inner diameter of 3 m and the height of 4 m, possesses the video transmission function and allows most of the small-scale underwater vehicle's overall stability and capacity to be tested possible. To tackle the leakage and ensure the stability of the chamber, this paper proposes a novel sealing method, which adopts the combination of anti-shear block device and four O-ring seals and has the advantage of no need of manual pre-tightening and of sufficient shear resistance. The performance and strength analysis of the chamber were carried out by Ansys/Workbench finite element analysis software. Furthermore, The high-pressure chamber was manufactured and its experiment verification results indicate that with larger containment volume and more advanced control system it could work reliably, which made it feasible for its engineering application. • A high-pressure chamber is the main equipment required for simulating deep-sea operational environment. • With the maximum working pressure 60 MPa, the high-pressure chamber has the inner diameter of 3 m, the height of 4 m. • The chamber possesses the video transmission function. • The performance and strength analysis of the high-pressure chamber were carried out by Ansys/Workbench FEA.. • Both the simulation and the experiment show that the chamber works reliably and is feasible for engineering application [ABSTRACT FROM AUTHOR]

• First report of via-less planar coil based magnetic sensors fabricated in a single metal level. • The proposed sensors are advantageous over conventional spiral coil based sensors regarding fabrication easiness and heating losses. • Analytical model is developed for the proposed induction-balance sensor which is used for the design. • Experimental results of the same are verified using finite element analysis. The emerging field of micro dimensioned biomedical sensors involves tremendous research to detect biomolecules and pathogens with an improved sensitivity and a low limit of detection. The use of magnetic labels in biosensors has increased so much over the past years due to unique advantages of magnetic sensing techniques. Planar microcoil based magnetic biosensors help to reduce the system size and improve the sensitivity. This paper proposes non-spiral planar microcoil based magnetic sensors which are advantageous over conventional spiral coil based sensors regarding fabrication easiness and heating losses. The method of microfabrication of the coil sensor described in this paper makes use of a single mask process which is the simplest among all existing processes. Non-spiral planar microcoil sensors based on induction-balance and differential sensing principles are studied in this work. Also, an analytical model is developed to design the dimensions of the sensing coil. Comprehensive finite element analysis of the sensors is performed, and the results are compared with the experimental outcomes. A comparative study of the proposed sensors with the existing planar coil magnetic sensors is also presented to show the advantages of the proposed coil sensors over the existing ones. [ABSTRACT FROM AUTHOR]