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Multiscale agent-based modeling frameworks have recently emerged as promising mechanobiological models to capture the interplay between biomechanical forces, cellular behavior, and molecular pathways underlying restenosis following percutaneous transluminal angioplasty (PTA). However, their applications are mainly limited to idealized scenarios. Herein, a multiscale agent-based modeling framework for investigating restenosis following PTA in a patient-specific superficial femoral artery (SFA) is proposed. The framework replicates the 2-month arterial wall remodeling in response to the PTA-induced injury and altered hemodynamics, by combining three modules: (i) the PTA module, consisting in a finite element structural mechanics simulation of PTA, featuring anisotropic hyperelastic material models coupled with a damage formulation for fibrous soft tissue and the element deletion strategy, providing the arterial wall damage and post-intervention configuration, (ii) the hemodynamics module, quantifying the post-intervention hemodynamics through computational fluid dynamics simulations, and (iii) the tissue remodeling module, based on an agent-based model of cellular dynamics. Two scenarios were explored, considering balloon expansion diameters of 5.2 and 6.2 mm. The framework captured PTA-induced arterial tissue lacerations and the post-PTA arterial wall remodeling. This remodeling process involved rapid cellular migration to the PTA-damaged regions, exacerbated cell proliferation and extracellular matrix production, resulting in lumen area reduction up to 1-month follow-up. After this initial reduction, the growth stabilized, due to the resolution of the inflammatory state and changes in hemodynamics. The similarity of the obtained results to clinical observations in treated SFAs suggests the potential of the framework for capturing patient-specific mechanobiological events occurring after PTA intervention. [ABSTRACT FROM AUTHOR]

The metal-matrix composites (MMCs) with biomimetic bricks-and-mortar architectures have been experimentally demonstrated to exhibit excellent strength-ductility match. Here, biomimetic bricks-and-mortar architecture mimicking masonry bonds was introduced in numerical models. By translating perpendicular layers on stack bond model, 1/2 running and running bond models were established. The results reveal that elongation of running bond model is the highest (4.77%), which is ∼ 1.5 times as that of stack type model. The strength of these models is similar (330 ± 1 MPa). However, it is the trade-off between load bearing capacity and fracture of SiC particles. In the stack bond model, over a small junction layer area led to a relatively straight crack path and thus lower elongation. On the contrary, running bond model shows a zigzag main crack. So, the main crack deflects frequently with high energy consumption. Furthermore, crack deflection into matrix cell increases propagation resistance, leading to the highest elongation in the running bond model. Therefore, the biomimetic bricks-and-mortar architecture delays and deflects main crack propagation. These findings have significant implication for the architecture design of advanced composite materials. [ABSTRACT FROM AUTHOR]

This paper presents an optimum design of a coaxial magnetic gear (CMG) Integrated with a Permanent Magnet Synchronous Generator (PMSG) of a wind turbine using a pelican optimization algorithm (POA) launched in 2022. In order to evaluate the proposed system design based on POA, the well-known Particle Swarm Optimization (PSO) is implemented for the same CMG under the same conditions and constraints. Also, a Taguchi-method-based sensitivity analysis for the key design variables is employed to determine their impact on the system’s performance. The optimization process for the CMG design based on POA and PSO is executed based on the 2-D Finite element analysis (FEA) using the Finite Element Method Magnetics (FEMM) program. The results obtained from the POA and PSO are compared and analyzed. The results underline that the optimum design for the CMG/PMSG integrated system based on POA achieves more torque/weight ratio and then more generated power and currents as compared to PSO. It is concluded that the proposed design based on POA gives a superior and efficient design with substantial stability and rapid convergence.Article Highlights: The article designs a coaxial magnetic gear (CMG) based on a pelican optimization algorithm (POA) presented in 2022. A 2-D finite element analysis is employed to calculate the optimal torque produced by the POA. A comparative study is presented between the results of the POA, and a well- known optimization called the Particle swarm Optimization (PSO) for the same CMG. [ABSTRACT FROM AUTHOR]

Continuous fiber-reinforced composites are increasingly used in industry for their superior specific modulus and strength. The curing process-induced deformation (PID) has been a critical problem during manufacturing, which always exhibits dispersed values even if the curing process curve and structural parameters remain consistent. This work conducted probability prediction of PID for V-shape composite structures based on the FEM method and data mining. A sequential coupling thermal–chemical–mechanical coupling FE model is established in ABAQUS. The prediction accuracy of the included angle between two sides is verified by the experimental results. Material parameter uncertainties are considered for V-shape structures with different radii and thicknesses. Based on the dataset from the FE model, a decision tree is established and trained to analyze the sensitivity and to predict the probability distribution of PID. The results show that PID increases with the coefficients of thermal expansion in the in-plane perpendicular fiber direction and out-of-plane normal direction. The data-mining method is accurate enough for the PID prediction, and its efficiency provides an additional calculation option in engineering applications. [ABSTRACT FROM AUTHOR]

The seismic behavior of steel reinforced ultra-high strength concrete (SRUHSC) composite frame was investigated through finite element analysis (FEA) modeling. A FEA model for the seismic analysis of the SRUHSC frame was first established and verified with test results. The numerical model was subsequently used to study the seismic performance of the SRUHSC frame, including the P-Δ skeleton curves, the stiffness degradation, the failure mode, the subsequence mechanisms of plastic hinges and the stress–strain distribution. Finally, a parametric study was carried out to investigate the effect of salient parameters on the behavior of the SRUHSC frame. It was found that with the increment of the concrete strength, yield strength of steel, and linear stiffness ratio of beam to column, the horizontal load-bearing capacity and the elastic stiffness of the structure were improved, but there was no significant effect on the ductility. With the increment of the volume stirrup ratio and structural steel ratio, the horizontal load-bearing capacity and the ductility of the structure were both improved. However, with the increment of the axial-load ratio, there was no obvious change in the elastic stiffness of the structure, but the horizontal load bearing capacity and the ductility of the structure decreased obviously. In addition, the accuracy of a concrete constitutive model in the different degrees of constraint for the SRUHSC frame proposed by the authors was verified with the FEA model. [ABSTRACT FROM AUTHOR]

A significant feature about hybrid structures is the strengthening of critical areas in order to increase the load capacity of the beams. This research evaluates the energy absorption capability and bending collapse behavior of an aluminum hat‐section with adhesively bonded of carbon fiber reinforced plastic (CFRP) as a partial reinforcement (PR) hybrid beam. The aluminum layers and processed CFRP laminates were bonded with adhesive joints to produce the beams with varied layups for hybrid beams. The specimens showed a range of bending collapses, and the hybrid specimens' peak load and load drop differed depending on failure mechanism. The experimental results reveal that the amount of SEA of the hybrid beam specimens was higher compared with that of the aluminum beam, with Al/CFRP [0/90]S PR hybrid beam exhibiting an 85.9% improvement in SEA value. Subsequently, FE models of aluminum and hybrid beams were developed for bending collapse analysis, and the finite element results were consistent with the experimental specimens' validation. In addition, the consequences of progressive damage failure in the interface effect and transverse matrix damage in various layups were investigated. Eventually, the Kecman model is used to perform analytical modeling of hybrid and aluminum beams in order to examine the impact of CFRP partial reinforcing components based on various bending moment hinge lines. Highlight: Bending characteristics of adhesively bonded partially reinforced Al/CFRP beamExperimental and numerical investigation on the beams under three‐point bendingAnalytical study for the prediction of energy absorption characteristicsA good agreement between numerical, theoretical and experimental results [ABSTRACT FROM AUTHOR]

Through simulation based on the Workbench platform in ANSYS the optimal laser remelting process parameters were identified to achieve the maximum performance of a Ni60 coating laser clad onto a H13 steel surface. Laser remelting with a fibre laser was conducted according to the optimal process parameters obtained and the coating morphology, microstructure and microhardness after remelting were analysed. The results show that when the laser power was 1200 W and the scanning speed was 4 mm/s the remelted coating has the smallest residual stress value, pores in the coating were basically eliminated, the organization was dense, the hardness improved and the coating quality was the best. When the laser power was 900 W and the scanning speed was 2 mm/s the maximum residual stress value of the remelted coating was slightly smaller than that of the un-remelted coating, the coating morphology quality was better, and there were very few bubbles. [ABSTRACT FROM AUTHOR]

This research presents a comprehensive dynamic finite element analysis (FEA) of a cryogenic fuel tank made from an innovative aluminium/lithium–graphene nano-composite material, assessing its suitability for aerospace launch vehicles carrying cryogenic hydrogen and oxygen. The study focuses on the effects of lightweighting, utilizing 0.5 wt.% reinforced graphene in the Al 2195 matrix, a material poised to revolutionize the aerospace industry. Objectives include developing a digital twin of the fuel tank, CAD modeling to aerospace standards, and conducting ANSYS simulations under launch conditions to evaluate stress, strain, and deformation. Numerical results reveal a significant weight reduction of approximately 19,420 kg and a notable maximum stress reduction of 1.3% compared to traditional Al 2195 alloy tanks. The novelty of this research lies in its pioneering analysis of aluminium/lithium–graphene composites for lightweighting in cryogenic fuel tanks under space launch conditions. Conclusions affirm the composite's viability, advocating for the development of lighter yet robust aerospace structures and fostering innovation in spacecraft design and materials science. [ABSTRACT FROM AUTHOR]

The purpose of this finite element analysis (FEA) was to evaluate the stress distribution within the prosthetic components and bone in relation to varying cement thicknesses (from 20 to 60 μm) utilized to attach a zirconia crown on a conometric cap. The study focused on two types of implants (Cyroth and TAC, AoN Implants, Grisignano di Zocco, Italy) featuring a Morse cone connection. Detailed three-dimensional (3D) models were developed to represent the bone structure (cortical and trabecular) and the prosthetic components, including the crown, cement, cap, abutment, and the implant. Both implants were placed 1.5 mm subcrestally and subjected to a 200 N load at a 45° inclination on the crown. The results indicated that an increase in cement thickness led to a reduction in von Mises stress on the cortical bone for both Cyroth and TAC implants, while the decrease in stress on the trabecular bone (apical zone) was relatively less pronounced. However, the TAC implant exhibited a higher stress field in the apical area compared to the Cyroth implant. In summary, this study investigated the influence of cement thickness on stress transmission across prosthetic components and peri-implant tissues through FEA analysis, emphasizing that the 60 μm cement layer demonstrated higher stress values approaching the material strength limit. [ABSTRACT FROM AUTHOR]

The utilization of 3D printing metals has gained considerable traction as a manufacturing technique within the automotive and aerospace sectors, leading to a demand for more efficient and cost-effective methods. In this article, the connecting rod (CR) of the two-wheeler's four-stroke engine underwent a redesign, analysis, and printing process using SS17-4PH gas atomized stainless steel powder through selective laser melting (SLM). The redesign aimed to reduce weight while maintaining strength in SolidWorks. Ansys 18.1® was used to perform finite element analysis (FEA). A comparison was made between the overall deformation, elastic strain, Von-Mises stress, safety factor, life, damage, and weight reduction of the optimized CRs and the original CR. The analysis was conducted under a load of 616 N, which is double the actual load on the CR. Subsequently, the optimized CR was printed using SLM. The study revealed that the weight of the optimized CR is significantly lower than that of the original. Furthermore, the modified CR is expected to have a similar lifespan to the original CR. [ABSTRACT FROM AUTHOR]

Previous investigations have primarily focused on the use of circular basalt fiber reinforced polymer (BFRP) bars in concrete compression members, neglecting the application of these lightweight composites in different structural sections. This study aims to address this research gap by examining the structural efficiency of square concrete compressive members reinforced with various BFRP sections. A total of eight samples were cast, including seven with BFRP angle sections, BFRP plate sections, BFRP tubes, and BFRP circular rebars, and one control sample with conventional steel rebars as the main reinforcement and stainless steel rebars as lateral reinforcement. All samples had a square cross-section of 200 mm width and 1200 mm height, except for the BFRP tube compressive member, which had a cross-section of 180 mm × 180 mm and the same height. The experimental results demonstrated that failure patterns were influenced by the reinforcement material, reinforcement section, and vertical spacing of stainless-steel stirrups. The sample with steel reinforcement exhibited the highest strength of 1451 kN. The ultimate strength reductions for samples with BFRP angle sections, BFRP plate sections, BFRP tubes, and BFRP circular rebars were 22%, 10.3%, 49.6%, and 10%, respectively. The study found that the vertical spacing of ties significantly impacted the load–deflection behavior. For angle section BFRP rebars, increasing the tie spacing from 50 to 100 mm resulted in a 9.50% increase in strength and a 22.20% increase in axial deflection. In contrast, for plate section BFRP rebars, increasing the tie spacing led to a 14.2% decrease in load and a 5.7% decrease in deflection. Members reinforced with BFRP circular rebars showed a 4% decrease in strength and a 13.4% increase in deflection. A finite element analysis (FEA) model was developed to evaluate the structural efficiency of members reinforced with BFRP sections and to conduct a parametric investigation. The concrete damaged plasticity (CDP) model was employed in the FEA to simulate concrete behavior. The proposed FEA model showed discrepancies of 7.2% for the ultimate load and 5.5% for the equivalent deflection and accurately captured crack patterns. Additionally, to compare with theoretical computations, predictions from three international codes were calculated to highlight differences between experimental measurements, FEA results, and theoretical predictions. [ABSTRACT FROM AUTHOR]

This paper presents a mesoscale damage model for composite materials and its validation at the coupon level by predicting scaling effects in un-notched carbon-fiber reinforced polymer (CFRP) laminates. The proposed material model presents a revised longitudinal damage law that accounts for the effect of complex 3D stress states in the prediction of onset and broadening of longitudinal compressive failure mechanisms. To predict transverse failure mechanisms of unidirectional CFRPs, this model was then combined with a 3D frictional smeared crack model. The complete mesoscale damage model was implemented in ABAQUS®/Explicit. Intralaminar damage onset and propagation were predicted using solid elements, and in-situ properties were included using different material cards according to the position and effective thickness of the plies. Delamination was captured using cohesive elements. To validate the implemented damage model, the analysis of size effects in quasi-isotropic un-notched coupons under tensile and compressive loading was compared with the test data available in the literature. Two types of scaling were addressed: sublaminate-level scaling, obtained by the repetition of the sublaminate stacking sequence, and ply-level scaling, realized by changing the effective thickness of each ply block. Validation was successfully completed as the obtained results were in agreement with the experimental findings, having an acceptable deviation from the mean experimental values. [ABSTRACT FROM AUTHOR]

The present study aimed to delve into the root cause failure analysis of a carbon steel member (Grade Q235C) within a high-voltage transmission tower which was subject to self-weight (approximately 43 kg) and wind load only (calculated at 2787.35 Pa). Examination of the fracture surface revealed the presence of beach marks and ratchet marks which indicates that the carbon steel member (a square hollow section equipped with two bolted supporting plates positioned 1.7 meters away from the failed welded plate) experienced failure attributed to wind-induced fatigue along the weld joint. No abnormalities were observed in the microstructure and the weld zone predominantly featured a ferrite phase and grain boundary pearlite. However, the finite element analysis conducted using Abaqus software demonstrated that the steel member at the weld joint should not have failed under normal circumstances. The critical finding was that the failure occurred due to the loosening of bolted supporting plates located within a distance of 1.7 meters from the welded joint. As a consequence of the supporting bolted joint becoming loosened, a Von Mises stress of approximately 400 MPa manifested at the welded joint, resulting in an abrupt failure. [ABSTRACT FROM AUTHOR]

Acromial stress fractures (ASFs) after reverse total shoulder arthroplasty (RSA) can have a potentially devastating impact on shoulder function. They are often difficult to effectively treat. Multiple studies have shown a higher incidence of ASF after RSA in patients with cuff tear arthropathy (CTA). This study introduces and explores a new hypothesis. Our hypothesis is that 1) patients with CTA experience a preoperative pathologic superiorly directed force on their acromion, and 2) this leads to acromial bending moments on the acromion that are very different from patients with glenohumeral osteoarthritis (GHOA) and after RSA, and finally 3) these pathologic loads may result in abnormal bony remodeling and adaptations in CTA, which may then predispose patients to ASF after RSA. A finite element analysis model was developed to compare three loading conditions on the acromion: preoperative CTA, preoperative GHOA, and postoperative-RSA. Regions of the highest tensile and compressive stresses were identified and compared between groups. The finite element analysis model presented shows that patients with a preoperative diagnosis of CTA experience a stress distribution reversal after RSA, whereas GHOA patients do not. The results support that in CTA, the humerus produces pathologic strains and torques on the acromion. Over time, the acromion may slowly remodel in response, resulting in bony adaptations. Abrupt reversal of stresses and strains in CTA after RSA may lead to ASFs, as the acromion has adapted to a different stress pattern. This study introduces one potential contributing factor for the higher rates of ASF after RSA in patients with a preoperative diagnosis of CTA; understanding this phenomenon is the first step to preventing it. Once the forces seen in CTA are abruptly reversed after RSA, the biological race is on between the formation of an acromial stress fracture and the body's ability to again remodel the acromion to accommodate its new loading state. Additional clinical studies are needed to further investigate this new theory. [ABSTRACT FROM AUTHOR]

The parasymphysis area of the mandible is highly dynamic because it is subjected to both occlusal and muscular forces. As a result, the fractures in this transition zone have a special pattern, posing a challenge for surgeons whether to use one miniplate versus two miniplates, as per Champy's recommendations. The commonest complication resulting to treat this area is mental nerve paraesthesia due to the dissection and stretching of the nerve. Hence, an in vitro research study of a newly designed 'Zeta' miniplate is performed, to evaluate the biomechanical behaviour using finite element (FE) analysis and biomechanical analysis along with a comparison study with the conventional miniplate configurations. The results showed that the Zeta miniplate produces the lowest stresses 17.511 MPa and the least total structural deformation of 0.0011 mm after applying the maximum occlusal bite force. On application of torsional load, total structural deformation was 0.0004 mm and von Mises (VM) stress value was 0.24 MPa which was lowest when compared with the two miniplate system. Hence, the newly developed Zeta miniplate is superior in terms of stability. Another benefit of its design is that it helps in preventing mental nerve paraesthesia and tooth root damage while fixing and stabilising the fractured bony segments. [ABSTRACT FROM AUTHOR]

Based on stress transfer relationship of fiber reinforced composite layer, damping layer and stiffeners, this study presents a novel dynamic analytical model in order to evaluate the dynamic characteristics of a composite damping plate with randomly oriented carbon nanotube reinforced stiffeners. Both an energy method and complex modulus theory are used to derive the vibration equations. Experiments and numerical simulations are adopted for confirming the correctness of the analytical findings. Furthermore, the model is utilized to investigate the impact of structural variables on the dynamic properties, including the modal loss factor and first-order natural frequency. [ABSTRACT FROM AUTHOR]

Precast concrete structures are popular in the building industry because of their high efficiency and environmental friendliness. In this paper, the U-type reinforcement ferrule connection technique was applied to study the seismic performance of precast concrete shear walls. Five shear wall finite element models and four shear wall specimens were prepared. Both experiments and finite element analysis were conducted to explore the impact of parameters on the work performance of precast reinforced concrete shear walls, such as the variety of post-cast concrete, the form of horizontal joints, and the buckle length of U-type reinforcements. On this basis, the mechanism of failure as well as the characteristics of hysteresis, ductility, and energy dissipation capacity were analyzed. According to the analytical results, the cast in situ reinforced concrete shear wall is inferior to the precast shear wall with post-cast epoxy resin concrete in terms of seismic performance. In addition, the specimen with a keyway on the horizontal joint interface outperforms the specimen without a keyway. With an increase in the buckle length of the U-type reinforcement, there is a rise in the sectional height and stiffness of the hidden beam at the bottom of the wall, while the horizontal load-bearing capacity of the wall is improved. However, its ductility and energy dissipation capacity are decreased. As revealed by a thorough analysis, the construction scheme most suitable for precast shear wall horizontal joints adopts epoxy resin concrete as the post-cast material, the buckle length of U-type reinforcements is approximately one-third the height of the horizontal joint, and there is a keyway at the interface of the joint. [ABSTRACT FROM AUTHOR]

The crack propagation in composite material due to thermal loading and environmental conditions is a serious issue. The study of the fracture propagation in a composite laminate will help understand the response of the structures under various loads. In the present study, a composite laminate is modelled with an elliptical cut-out and the fracture behaviour of the structure under the application of the thermal load is studied. Finite element analysis was used to obtain the stresses in the structure. Thermal load is applied on the laminate in the form of a constant temperature. The temperatures used in the present study are 30°C, 80°C, 130°C, and 180°C. The stresses in the laminate increased with the increase in the thermal load. The stresses in the normal direction are major stresses in the structure. The stresses in the composite laminate at the thermal load of 180°C is nearly nine times the stress at the 30°C in certain conditions. [ABSTRACT FROM AUTHOR]

Elbow joint rehabilitation presents a formidable challenge, underscored by the joint’s complex biomechanics and high vulnerability to injuries and degenerative conditions. Despite the advancements in rehabilitative technology, current solutions such as rigid exoskeletons often fall short in providing the precision, flexibility, and customization needed for effective treatment. Although traditional robotic aids, such as rigid exoskeletons, help recover, they lack in providing sufficient flexibility, comfort, and easy customization with no need for complicated calculation and complex design considerations. The introduction of soft pneumatic muscles marks a significant development in the rehabilitation technologies field, offering distinct advantages and unique challenges when compared to conventional rigid systems. These flexible actuators closely mimic the elasticity of biological tissues, improving safety and interaction between humans and machines. Designed for individualized therapy, its versatility allows application in various rehabilitation scenarios, from clinical settings to home settings. The novelty of this approach lies in the development of biomechanically-compliant soft pneumatic muscles optimized for precise rotational control of the elbow joint, coupled with an advanced deep learning-based motion tracking system. This design overcomes limitations in force control, stability, and pressure requirements found in existing pneumatic-based systems, improving the safety and efficacy of elbow rehabilitation. In this study, the design, fabrication and systematic evaluation of a soft pneumatic muscle for elbow rehabilitation are presented. The device is designed to closely simulate the complex biomechanical movements of the elbow, with a primary focus on the rotational motions that are essential for controlling flexion and extension, as well as positioning the wrist during grasping tasks. Through the integration of precise geometric parameters, the actuator is capable of controlled flexion and extension, reflecting the natural kinematics of the elbow. Employing a rigorous methodology, the research integrates finite element analysis with empirical testing to refine the actuator’s performance. Under varying air pressures, the soft muscle demonstrated remarkable deformation along the X-axis (10–150 mm) and the Y-axis, indicative of its symmetrical rotational behavior, while maintaining minimal elongation along the Z-axis (0.003 mm max), and proper lifiting force under a maximum wight of 470 gm. highlighting the stability and targeted response of the device to pneumatic actuation. A specialized experimental apparatus comprising a 3D environment, a pneumatic circuit, a LabVIEW-based control system, and a deep learning algorithm was developed for accurate position estimation. The algorithm achieved a high predictive accuracy of 99.8% in spatial coordination tracking, indicating the precision of the system in monitoring and controlling the actuator’s motion.

Insulated cross-arms for overhead transmission lines have become increasingly common in the past decade. The 3D finite element analysis (FEA) of the electric field distribution in insulated cross-arms is particularly intriguing due to the differences from conventional glass or ceramic insulators. The complex geometry of composite cross-arms, which feature four separate insulator strings and varying shed profiles, poses a challenge in modelling them using 3D FEA packages. The findings indicate that insulated cross-arms can operate within suitable parameters for traditional composite insulators. This paper presents and analyses the electric field distribution around an insulated cross-arm, which aims to replace existing high-voltage insulators and the steel cross-arms of transmission towers. The design of grading devices plays a crucial role in ensuring the safety of these structures. The use of grading ring devices at both ends of the insulator has proven effective in relieving stress on the insulator string under normal and abnormal conditions, enabling the insulated cross-arm to function effectively with conventional composite insulators. Significant reductions in electric field strength were observed, amounting to approximately 35.93 % inside the core, 31.14 % on the core surface, 35.64 % through the shed, and 16.67 % above the shed for compression members. For tension members, reductions from the low-voltage end to both ends were around 33.82 % inside the core, 38.55 % on the core surface, and 17.48 % through the shed. However, an 8.43 % increase was observed above the shed, indicating a deviation from the decreasing trend observed in other areas. These research findings provide valuable insights for designing and managing high-voltage systems, ensuring effective insulation and enhanced safety. It benefits electrical utilities and transmission line manufacturers by improving reliability and safety for overhead transmission lines.

Most of the electrical equipment responsible for the control within a power plant is configured in cabinet form and fixed using post-installed anchors. Shaking table testing to evaluate the seismic performance of cabinets does not simulate the same installation conditions as on-site, but simply welds the bottom of the cabinet to the top surface of the shake table to assess the structural integrity. The seismic performance evaluation of post-installed anchors is typically conducted indirectly through material testing, making it necessary to compare the performance under on-site conditions to ensure reasonable measurement. This study fabricated a structure as a replacement for the cabinet, fixed it using post-installed anchors, and applied static loads to measure the pull-out load transmitted to the anchors. The measured results were then compared with those obtained from material testing. Consequentially, the pull-out load in the test reflecting on-site conditions was approximately 10% higher than in the material test. So the current way of indirectly evaluating the performance of post-installed anchors is deemed reasonable based on the derived results. To validate the reliability of the experimental study, a numerical study was conducted, and the results showed an error range of around 1%, indicating reasonable and consistent findings.

A new data-driven continuum model based on an artificial neural network is developed in this study for a new three-dimensional lattice-structured material design. The model has the capability to capture and predict the nonlinear elastic behaviour of the specific lattice-structured material in the three-dimensional continuum description after being trained through the appropriate dataset. The essential data as the input ingredients of the data-driven model are provided through a hybrid method including experimental and unit-cell level finite element simulations under comprehensive loading scenarios including uniaxial, biaxial, volumetric, and pure shear loading. Furthermore, the lattice-structured samples are also fabricated using SLA additive manufacturing technology and the experimental measurements are performed and used for validation of the model. This then illustrates that the current model/methodology is a robust and powerful numerical tool to conduct the homogenization in complex simulation cases and could be used to accelerate the analysis and optimization during the design process of new lattice-structured materials. The model could also easily be used for other engineered materials by updating the dataset and re-training the ANN model with new data.

As the main load bearer throughout the gait cycle, the tibia is a crucial bone in the lower leg that distributes ground reaction forces with each stride. Comprehending the distribution of stress inside the tibia is essential for both avoiding fractures and developing efficient methods of redistributing load to promote healing and biomechanical correction. The study examined the stress, strain, and deformation encountered by the tibia over a 7-s walking cycle using an ANSYS workbench software, using tibia bone under a period of force applied to the boundary condition at intervals of 0.2 s. The tibia encounters stress levels varying from 0 to 1,400 N, exhibiting a regular pattern that aligns with the loading attributes often associated with traditional walking. The research conducted in this study identified the occurrence of maximum stress levels, measuring 25.45 MPa. Additionally, related peak elastic strains and deformations were observed, measuring 2.19 × 10−3 and 2.43 mm, respectively. The patterns that have been seen indicate that there is an initial contact of the foot with the ground, followed by the bearing of weight and subsequently the toe-off. These observed patterns closely resemble the natural motion of the foot during the act of walking. Temporal fluctuations in elastic strain through the tibia throughout a gait cycle reveal that the strain is mostly cantered at the medial surface of the tibia. Additional investigation into the elastic properties and overall deformations of the tibia yielded valuable observations on prospective areas of interest within the bone’s structure. These findings are of utmost importance for biomechanical assessments and the identification of potential injury hazards in subsequent research endeavours.

Directed energy deposition additive manufacturing (DED-AM) has gained significant interest in producing large-scale metallic structural components. In this paper, a knowledge-based machine learning (ML) approach, combining both physics-based simulation and data-driven modelling, is proposed for a study on thermal variables of DED-AM. This approach enables both forward and backward predictions, which breaks down the barriers between the basic process parameters and key process attributes. Process knowledge plays a critical role to enable the prediction and enhance the accuracy in both prediction directions. The proposed ML approach successfully predicted the thermal variables of wire arc based DED-AM for forward modelling and the process parameters for backward modelling, typically within 7% errors. This approach can be further generalised as a powerful modelling tool for design, control, and evaluation of DED-AM processes regarding build geometry and properties, as well as an essential constituent element in a digital twin of a DED-AM system.

Inspired by the property mechanism principles of C. squamiferum (impact resistance) and bamboo (energy absorption), a bionic bidirectional gradient NiTi alloy was developed and fabricated by the innovative time-varying deposition strategy (TVDS), including different process parameters (the laser power and scanning speed), different scanning paths (alternative optimised spiral pattern and x-axis rotation pattern) and interlayer interval time. This study explores how TVDS influences the printability, microstructure evolution, phase transformation behaviour, mechanical properties, and superelasticity response. However, the element distribution tests discover mutation points under various regions in the GD-X-GD-Z (V1) and GD-X-LD (H1) planes to determine the feasibility of the bionic bidirectional gradient using TVDS. The recovery ratios along the H1 and V1 planes after 1st and 10th cycles are 90.7% and 88.4%, 82.6% and 67.5%, respectively. The numerical modelling framework is established to elucidate the thermal fields generated by TVDS and provide support for the experimental data.

The inherent manufacturing defects in laser powder bed fusion (LPBF)-processed samples leads to deviations from results of finite element analysis (FEA) using the designed model. To systematically evaluate process-induced defects and elucidate their effect, a novel methodology, combining statistical analysis, precision computed tomography (CT) characterisation techniques, mechanical properties assessments and FEA, has been developed. Compared to designed models, CT reconstructed models consider defects, which may affect mechanical properties evaluation, especially along the building direction. FEA based on the CT reconstructed model can more accurately display the stress distribution and the anisotropy of samples. Results indicate that mechanical properties correlate with geometric structure and building direction. Anisotropy becomes more pronounced at a strut diameter of 1.0 mm, the universal anisotropic index AU can reach to 6.31. Overall, this method improves predictive ability by elucidating structure–property relationships in LPBF-processed lattice structures, offering insights into the efficient design for LPBF-processed lattice structures with desirable mechanical properties.