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Purpose: This paper aims to compare and evaluate the influence of package designs and characteristics on the mechanical reliability of electronic assemblies when subjected to harmonic vibrations. Design/methodology/approach: Using finite element analysis (FEA), the effect of package design-related parameters, including the interconnect array configuration, i.e. full vs perimeter, and package size, on solder mechanical stresses are fully addressed. Findings: The results of FEA simulations revealed that the number of solder rows or columns available in the array, could significantly affect solder stresses. In addition, smaller packages result in lower solder stresses and differing distributions. Originality/value: In literature, there are no papers that discuss the effect of solder array layout on electronic packages vibration reliability. In addition, general rules for designing electronic assemblies subjected to harmonic vibration loadings are proposed in this paper. [ABSTRACT FROM AUTHOR]

To analyze the dynamic response of a rigid M-shaped jumper subjected to combined internal and external flows, a one-way coupled fluid–structure interaction process is applied. First, CFD simulations are conducted separately for the internal and external fluid domains. The pressure histories on the inner and outer walls are exported and loaded into the finite element model using inverse distance interpolation. Then, FEA is performed to determine the dynamic response, followed by a fatigue assessment based on the obtained stress data. The displacement, acceleration, and stress distribution along the M-shaped jumper are obtained. External flow velocity dominates the displacements, while internal flow velocity dominates the vibrations and stresses. The structural response to the combined effect of internal and external flows, plus the response to gravity alone, equals the sum of the structural responses to internal flow alone and external flow alone. Fatigue damage is calculated for the bend exhibiting the most intense vibration and higher stress levels, and the locations with significant damage correspond to areas with high maximum von Mises stress. This paper aims to evaluate multiple flow fields acting simultaneously on subsea pipelines and to identify the main factors that provide valuable information for their design, monitoring, and maintenance. [ABSTRACT FROM AUTHOR]

The study presented in this paper was undertaken in response to two instances of unexpected blade breakage in the cutting blade used in a Carton Wrap machine (CW). Failure of the Al7075 alloy blade occurred at an indentation during typical operational loading conditions. Subsequent metallographic examinations of the fractured samples confirmed that both cases were attributed to fatigue failure. The main objective of this study is to investigate potential causes of fatigue failure in the CW blade using simplified linear elastic static numerical simulations through Finite Element Analysis (FEA). In this research, we employed the well-established Theory of Critical Distance (TCD), and this case study provided a contextualization at an industrial level. Furthermore, the analysis focused on a second key aspect: proposing a new blade geometry aimed at mitigating the identified issues and eliminating possible causes of failure. In this context, the actual stress concentration at the indentation was determined using the TCD with Line Method (LM). The results from the numerical simulations indicated that the new blade geometry significantly reduced stress concentration, resulting in a risk factor reduction of approximately four compared to the original blade design, even under non-optimal operating conditions. Overall, in conjunction with simple linear static FEA, the proposed numerical approach provided substantial support for designers, especially in fault analysis and when comparing different industrial solutions. [ABSTRACT FROM AUTHOR]

The reliability of high-voltage circuit breakers (HVCBs) depends critically on the dynamic characteristics of their hydraulic operating mechanisms (OMs). However, previous analyses have been limited to discrete components due to the lack of models capturing multi-physics couplings. This paper proposes a novel co-simulation approach for hydraulic OMs that enables system-level analysis. Specifically, the hydraulic system is modelled using the lumped parameter method, and the transmission mechanism is modelled via finite element analysis. The subsystem models exchange inputs and outputs through shared memory, realizing coupling without compromising simulation performance. Experiments on a 550 kV HVCB validate that the model accurately captures OM transient responses. The co-simulation framework has diverse capabilities, including predicting dynamics under varied operating parameters and quantifying stress distributions and response evolution patterns. Overall, this paper proposes an advanced multi-physics analysis capability for hydraulic OMs to support reliabilityoriented design and optimization. [ABSTRACT FROM AUTHOR]

The objective of this systematic review is to investigate the various approaches that have been undertaken in finite element analysis (FEA) of human–seat interactions and synthesize the existing knowledge. With advances in numerical simulation and digital human modeling, FEA has emerged as a powerful tool to study seating comfort and discomfort. FEA employs various biomechanical factors to predict the contact stress and pressure distribution in a particular seat design. Given the complexity of human–seat interaction, several modeling and processing steps are required to conduct realistic FEA. The steps of how to perform an FEA simulation on human–seat interactions, the different models used, the model mesh compositions, and the material properties are discussed and reviewed in this paper. This can be used as a guideline for future studies in the context of FEA of human–seat interactions. [ABSTRACT FROM AUTHOR]

Fretting wear in the contact area between the aero-engine blade tenon and turbine disk mortise has an important influence on the performance of the aero-engine. In this paper, the tenon joint structure of the DZ125/FGH99 superalloy material is taken as the research object, and the finite element model of the fir-tree tenon joint structure is established. Through subroutine invocation and mesh adaptive control technology, the fretting wear problem of dissimilar material contact pairs under composite load is numerically studied. The results show that for the specific tenon joint structure and load and boundary conditions studied in this paper, the maximum wear occurs on the contact surface of the first tooth, and the surface will show different partial slip states in different load cycles. The slip region always extends from the two contact edges to the interior, and the upper side has a larger range. Wear has a significant effect on the stress distribution and stick–slip state of the contact surface. The second and third teeth have a small amount of wear and are basically in a stick state during the entire wear process. Therefore, wear has little effect on the stress distribution and the stick–slip state of the contact surface. This study reveals the coupling relationship between the fretting wear and contact state of the tenon joint structure. [ABSTRACT FROM AUTHOR]

Due to the limitations of planar mode wharfs, this paper proposes a new type of wharf—the three-dimensional cantilevered wharf. The proposed wharf is defined as an improvement of the traditional wharf, extending the traditional wharf upward and cantilevering out to the sea. The three-dimensional cantilevered wharf is a composite truss structure that meets structural and functional requirements. The composite truss structure is formed by connecting the beams of frame structures as a whole. The material consumption of the three-dimensional cantilevered wharf is decreased by controlling stresses and optimizing components. A finite element model of the proposed wharf, with a length of 200 m, width of 105 m, and cantilever length of 80 m, was established to analyze the basic mechanical performance. In this paper, the force distribution of the pile foundation, the vertical force transfer efficiency of web members, the structural stiffness, and the natural frequencies of the proposed wharf are analyzed. Tests regarding the stress and stiffness of different plane cantilever trusses are carried out, and finite element analysis is used for comparison. The test results show that the high-rise cantilever truss has a great in-plane stiffness and a reasonable component stress distribution. Additionally, the three-dimensional cantilevered wharf significantly improves the utilization efficiency of the wharf. [ABSTRACT FROM AUTHOR]

The paper presents a study of the performance and development of unmanned ground vehicles (UGVs), establishing mathematical and numerical models of the chassis system. The model analysis is performed by 3D software package SolidWorks 2018 with finite element discretization. The mesh modelling and analysis are focused on studying the strength and stiffness of the robotic platform chassis and the distribution of stress and deformation in the extremal condition. The paper also presents an autopilot design with a new cascade control system for the autonomous motion of an unmanned ground vehicle based on proportional–integral–derivative (PID) and feedforward (FF) control. The PID-FF controller is part of a UGV used in a hybrid control system for precise control and stabilization, which is necessary to increase the vehicle motion stability and maneuver precision. The hybrid PID-FF control system proposed for the ground vehicle model gives satisfactory control quality while maintaining the simplicity of the control system. The presented tests performed in mechanical design and control analysis give good results and prove the usefulness of the designed unmanned device. [ABSTRACT FROM AUTHOR]

Fast growth of renewable energies has required addressing challenges such as generating the largest energy production possible throughout the equipment's lifespan and between its preventive and corrective maintenance intervals. Actions such as preventive maintenance, and improvement of the main components, mainly when it comes to reliability and predictability are of extreme importance to reach maximum generation. Due to the importance of the yaw drives for wind turbines, this paper aims to evaluate a failure that occurred on a cycloidal gearbox used in a drive of this kind. For the evaluation of the yaw drive, all the components were analyzed to determine the incurred fracture mechanism. Such analysis was performed by mapping all components, conducting a hardness test to check the components' mechanical properties, analysis of the fractured surfaces of the cycloidal disc, and numerical simulation (linear elastic) via the Finite Element Method (FEM) to check the stress distribution on the fractured part (cycloidal disc) under load, and theoretical calculation of the cycloidal disc lifespan. In addition, the stress distribution by FEM was compared with the broken regions of the physical part. To sum up, after all the evaluations, it is possible to claim the results demonstrate there was a premature fracture of the cycloidal disc that occurred due to the phenomenon of high cycle fatigue. [ABSTRACT FROM AUTHOR]

In this paper, the dynamic characteristics of inhomogeneous three-layer spheres under spherical wave induced by cyclic pressure are studied. The density is assumed to have a square of inverse proportional function distribution along the radius. Firstly, on the basis of Lamb decomposition and variable separation method, the analytical expression of spherical wave is conducted, which satisfies the stress equilibrium on the outer and inner surfaces of the sphere, and the Euler equation is obtained due to inhomogeneity. Next, algebraic equations with respective boundary conditions are composed and solved by effective truncation techniques. Finally, a comparison and discussion are conducted between the model presented in this article and the homogeneous model obtained by the Legendre polynomial expansion. Obtained results enable to reveal the influence on the dynamic stress concentration factor intensity under proper conditions. The conclusions of this article are verified by comparing the analytical solutions to the ones obtained by finite element method. This paper can provide a theoretical method for the analysis of mechanical properties of inhomogeneous multilayered spherical structure under dynamic loading. [ABSTRACT FROM AUTHOR]

This study investigates bidirectionally sinusoidal corrugated steel shells using finite element analysis (FEA) software, primarily ABAQUS 2017, supplemented by RFEM 6.05 for an initial result comparison. The research aims to establish a robust numerical solution to understand the structural behaviour of these shells under static and dynamic loading. Starting with meticulous calculations for a selected structural element, the paper emphasises a comparative analysis between ABAQUS and RFEM, offering valuable insights into simulating the responses of corrugated steel shells. A distinctive contribution of this research lies in its novel and comprehensive parametric analysis of these shells under static and dynamic loading, an area that has not been explored in previous studies. The study systematically explores various model parameters, including geometrical and mechanical properties, with detailed analyses revealing their influences on deformation, stress distribution, dynamic properties, and behaviour. Another key feature is the development of a coded script that systematically generates diverse numerical models, allowing for a thorough exploration of the structural system's response. This study advances our understanding of the structural behaviour of bidirectionally sinusoidal corrugated steel shells. These findings are set to enhance structural analysis and design practices by optimising parameters for improved performances in various engineering applications. [ABSTRACT FROM AUTHOR]

This study offers an in-depth structural analysis of the threading mechanism in a motorized leg-lengthening nail, a key device used in bone-lengthening surgeries. The primary aim is to assess the structural integrity and performance of the nail during the lengthening process. The paper starts with a comprehensive overview of the nail's design, historical background, and functionality, emphasizing the critical components of the lengthening mechanism. The methodology section details the structural analysis approach, incorporating both finite element analysis (FEA) and manual calculations. FEA simulations are employed to analyze the nail's behavior under compressive loads, considering realistic conditions such as the 95th percentile of human body weight. The analysis focuses on stress concentrations, deflections, and overall structural stability to pinpoint the potential weaknesses. Due to budget limitations that prevented the creation of physical prototypes, manual calculations were utilized to validate the FEA results. The findings identify stress concentrations, especially in the areas where male and female threads engage, leading to the design of recommendations to enhance strength and reliability. Experimental results corroborate the accuracy of the FEA simulations. The study concludes with suggestions for improving thread design, emphasizing safety, durability, and functionality. These recommendations aim to guide the future iterations of the motorized leg-lengthening nail, thereby promoting the development of safer and more effective devices for bone-lengthening surgeries. This structural analysis significantly contributes to understanding the mechanical behavior of the motorized leg-lengthening nail, playing a crucial role in advancing medical devices for bone-lengthening procedures. [ABSTRACT FROM AUTHOR]

This paper is focused on a new structural type - sandwich shell, which includes inner and outer shells connected by hoop connectors to achieve composite action; and a functional layer in the middle. Considering that the hoop connectors are not completely rigid, there will be limited slip between the inner and outer shells, which will lead to partial Degree of Composite Action (DCA). Due to the existence of the hoop connectors and shear lag effect, the stress distribution along the width direction of the shell is uneven, which can be described by effective width. Considering all these factors, this paper first develops an analytical model for sandwich shells with different configurations of connectors; and uses finite element analysis results to verify the analytical model. Next, a parametric study is conducted using the analytical model to study the effects of material strength, the ratio of the thickness of the functional layer to the thickness of the single layer shell, and the ratio of the arc length to the width of the sandwich shell on the effective width. It is found that DCA can significantly affect the stress and strain distributions of the sandwich shell. The effective width for 100% DCA can be used as a conservative value to represent those of other DCAs. Finally, a simplified calculation formula, which can be used in practical design, is derived based on the effective width for 100% DCA. [ABSTRACT FROM AUTHOR]

In this paper, a failure analysis of the TMT90m + composite wind turbine blade performed by combining numerical simulation and full-scale destruction tests is presented. The complex failure characteristics of the skin were studied in detail and a driving relationship was obtained. From the results, it was found that the stress concentration leading to local buckling was due to the geometric and layup nonlinearities of the destruction region. This in turn contributed to the successive occurrence of matrix failure and fiber failure. Further, by using the method of finite element secondary development, the accuracy of four commonly used failure criteria for wind blade failure prediction is discussed. From the results, it was found that the Chang-Chang model has ideal prediction accuracy and is more suitable for engineering applications in blade structure design. [ABSTRACT FROM AUTHOR]

In order to study the influence of slip structure on the mechanical behavior and residual strength of casing, parameters such as support force and friction force between slips and casing were derived based on the interaction relationship between slips and casing. Tensile tests were conducted on casing materials in this paper, and the working process of anchoring casing with single and double slips was simulated. The influence of indentation depth on the residual strength of casing was analyzed. The results show that the deformation of the casing is relatively severe when the single slip sealing force reaches 120 kN. According to the law of residual strength curve, there is a turning point where the stress concentration factor tends to be gentle, and the corresponding indentation depth value at this point increases with the increase in casing diameter. Single slips were unable to effectively bite into P110 and P125 casings, and the bite did not achieve the effect of setting the casing. However, when double slips were used to anchor the casing, the inner wall of the casing had deeper indentation, and the double slips could firmly seat the casing. These results indicate that replacing single slips with double slips can effectively achieve the setting effect. [ABSTRACT FROM AUTHOR]

In recent years, square hollow section (SHS) joints with concrete-filled square hollow section (CFSHS) chords have increasingly been used in truss bridges where the fatigue life reliability is a critical issue. In this paper, a finite element analysis was performed to investigate the SCFs in SHS-CFSHS T-joints under in-plane bending in the brace, axial force in the chord and in-plane bending in the chord. The finite element models were developed and validated with experimental results. Then a parametric study was conducted with a reasonable range of three key non-dimensional parameters, i.e., β (width ratio between brace and chord), 2γ (width–to–wall thickness ratio of the chord) and τ (wall thickness ratio between brace and chord). Consequently, the stress concentration factor formulae for the fatigue design of SHS-CFSHS T-joints were proposed through multiple regression analysis. For in-plane bending in the brace, the maximum stress concentration factors were found at lines B and C for thick-walled chords (2γ = 25.0), while the stress concentration factors at all the lines need to be checked for thin-walled chords (2γ < 16.0). Under axial force in the chord and in-plane bending in the chord, only stress concentration factors at lines C and D needed to be considered. A comparison of stress concentration factors between SHS-SHS and SHS-CFSHS joints showed reductions of 10~26% and 14~31% in stress concentration factors in SHS-CFSHS joints under axial force in the brace and in-plane bending in the brace, respectively. In addition, it showed a general increase in stress concentration factors in SHS-CFSHS joints under axial force and in-plane bending in the chord. This reduction is attributed to the reduction in chord face deformation benefiting from the in-filled concrete. Meanwhile, the stress concentration factors caused by loads in the chord are much lower than those caused by loads in the brace. This work complements earlier studies on SHS-CFSHS T-joints under axial force. [ABSTRACT FROM AUTHOR]

VLFSs (Very Large Floating Structures) are often assembled by multiple modules through connectors where the connector structure is prone to stress concentration. Therefore, the loads at the connectors have become a significant focus in VLFS design. In this paper, the FMFC (Flexible Module Flexible Connector) method, which can account for the elastic deformation of each module and the connector, is established in order to predict the coupling response of the connector and the platform. The finite element model of a dual-module transfer platform with a hinged connector is established and the modal shape characteristics of the entire structure are analyzed. The accuracy of the method is verified through a model test, where the model was scaled as 1:50. Furthermore, the RAOs (Response Amplitude Operators) of connector loads were calculated. It was found that the horizontal loads (along the x and y directions) were more sensitive to the wave direction. Furthermore, the wave direction where the maximum short-term significant value appears was not consistent with the direction of the maximum RAO. The loads response law of the VLFS with a hinged connector is summarized in this paper and provides a reference for the design of connectors. [ABSTRACT FROM AUTHOR]

The primary focus of this paper is to investigate the application of ANSYS Workbench 19.2 software's advanced feature, known as Separating Morphing and Adaptive Remeshing Technology (SMART), in simulating the growth of cracks within structures that incorporate holes. Holes are strategically utilized as crack arrestors in engineering structures to prevent catastrophic failures. This technique redistributes stress concentrations and alters crack propagation paths, enhancing structural integrity and preventing crack propagation. This paper explores the concept of using holes as crack arrestors, highlighting their significance in increasing structural resilience and mitigating the risks associated with crack propagation. The crack growth path is estimated by applying the maximum circumferential stress criterion, while the calculation of the associated stress intensity factors is performed by applying the interaction integral technique. To analyze the impact of holes on the crack growth path and evaluate their effectiveness as crack arrestors, additional specimens with identical external dimensions but without any internal holes were tested. This comparison was conducted to provide a basis for assessing the role of holes in altering crack propagation behavior and their potential as effective crack arrestors. The results of this study demonstrated that the presence of a hole had a significant influence on the crack growth behavior. The crack was observed to be attracted towards the hole, leading to a deviation in its trajectory either towards the hole or deflecting around it. Conversely, in the absence of a hole, the crack propagated without any alteration in its path. To validate these findings, the computed crack growth paths and associated stress intensity factors were compared with experimental and numerical data available in the open literature. The remarkable consistency between the computational study results for crack growth path, stress intensity factors, and von Mises stress distribution, and the corresponding experimental and numerical data, is a testament to the accuracy and reliability of the computational simulations. [ABSTRACT FROM AUTHOR]

The paper presents analysis of influence of change of physical parameters such as: temperature, friction coefficient and load, during the process of die forging. Optimization of the process effects in achieving high quality products, decreasing shaping resistance, and what follows - lower energy consumption. Temperature is the basic factor affecting the process of plastic working. Analyzing that influence in individual die fragments, allows to engineer the flow of shaped material. The QForm3D commercial program for finite element method calculations was used for numerical simulations. The paper presents multi-variant analysis of forging process with the usage of numerical simulation, which provided many valuable information concerning changes of key parameters, such as: temperature, stress and strain distribution and variations of technological parameters, as well as their mutual influence, difficult to obtain in analysis of industrial process. [ABSTRACT FROM AUTHOR]

This research paper presents a developed technique for Friction Stir Spot Welding (FSSW) to join similar aluminum sheets (6061), and then this technique was analyzed critically based on numerical simulation and experimental work. The objective of this Developed Friction Stir Spot Welding (DFSSW) is to avoid or at least reduce the keyhole defects by optimizing the design parameters of the process. The coupling problem (thermomechanical) was solved numerically using the finite element method to find the variations of temperatures and stress distributions in addition to the applied forces by the tool. Different parameters were considered in the numerical analysis, such as rotational speed and plunge depth. The experimental results proved the success of the developed technique by comparing the available results of tensile shear force with the results of other researchers that applied the traditional FSSW. It was obtained the highest tensile shear force (2388 N) under the optimal working and design conditions, when the rotational speed, plunging depth, height, and diameter of the sliced disc were 2100 rpm, 0.3 mm, 3.5 mm, and 12 mm, respectively. It was found that both the diameter and height of the sliced disc are significant parameters that ensure the success of this new technique when selecting the suitable values for these parameters. Otherwise, selecting unsuitable values of these parameters leads to appearing defects (e.g., flash) or the sample will fail under a low level of tensile shear force. The other essential advantage outcome point of this new technique was reducing the defect of the keyhole significantly compared with the results of typical Friction Stir Spot Welding. According to the results of the promising developed welding procedure that can be automated, it can be used widely in the industrial sectors. [ABSTRACT FROM AUTHOR]

The turbine disk-drum is one of the key components of an aero-engine and its assembly is connected with high-strength refined screws. But due to the uncoordinated rotation and deformation, the screws have abnormal wear damage. Through detailed contact stress analysis of screw body and component level using the finite element method, combined with experimental observation, the mechanism of wear damage of screw surface in screws is determined. It mainly includes the following: Firstly, the finite element method is used to calculate the deformation and stress distribution of the connecting screw of the turbine disk-drum assembly. Then, after the overspeed test, the morphology of the screws disassembled from the disk-drum assembly is evaluated. It was found that the wear degree in the circumferential direction and axial direction of the screw was quite different, that is, the screw wear experiment was consistent with the finite element analysis results. Finally, the influence of different rotation states and screw tightening states on screw wear was compared and analyzed. Conclusions obtained in this paper will be helpful to improve the assembly reliability of turbine drum. [ABSTRACT FROM AUTHOR]

This paper designs a two-degrees-of-freedom (DOF) compliant positioning stage with antagonistic piezoelectric actuation. Two pairs of PEAs are arranged in an antagonistic configuration to generate reciprocating motions. Flexure mechanisms are intentionally adopted to construct the fixtures for PEAs, whose elastic deformations can help to reduce the stress concentration on the PEA caused by the extension of the PEA in the other direction. Subsequently, the parameter and performance of the 2-DOF compliant positioning stage is optimized and verified by finite element analysis. Finally, a prototype is fabricated and tested. The experimental results show that the developed positioning stage achieves a working stroke of 28.27 μm × 27.62 μm. Motion resolutions of both axes are 8 nm and natural frequencies in the working directions are up to 2018 Hz, which is promising for high-precision positioning control. [ABSTRACT FROM AUTHOR]

This paper investigates the failure mechanism of the rear drive shaft in a modified pickup truck which had operated for about 3000 km. The investigation included macroscopic and microscopic evaluation to document the morphologies of the fracture surface, measurement of the material composition, metallographic preparation and examination, mechanical testing, and finite element modelling and calculations. The results obtained suggest that rotation-bending fatigue was the primary cause of the drive shaft failure. The crack initiation is located in the root of the machined threads on the drive shaft surface and expanded along the side of the machining line surface. The main cause of fatigue cracks is attributable to a high stress concentration owing to a large unilateral bending impact under overload. Meanwhile, the bidirectional torsional force also produces a higher stress concentration and thus accelerates the fatigue crack to expand radially along the surface. Furthermore, the hardness of the central section of the drive shaft was marginally below standard. This deficiency results in harm to the bearings and other mechanical components, as well as expediting the enlargement of cracks. Finite element analysis revealed significant contact stress between the bearing and drive shaft, with stress levels exceeding the fatigue limit stress of the parent material. This highlights the need for reevaluation of the heat treatment process and vehicle loading quality to enhance the drive shaft's longevity. [ABSTRACT FROM AUTHOR]

A multisubstructure-based method for assessing the deformation and stress of a fine-meshed model according to a coarse model was proposed. Integrating boundary conditions in a local fine-meshed model, a displacement mapping matrix from the coarse model to the fine-meshed model was constructed. The method was verified by a three-level panel in a fluid–structure interaction (FSI) framework by integrating the steady vortex lattice method (VLM). A comparison between the inner deformation distribution of the coarse model and that of the global fine-meshed model obtained from MSC.Nastran was carried out, and the results showed that the coarse model failed to demonstrate reliable strains and stresses. In contrast, the proposed method in this paper can effectively depict the inner deformation and critical stress distribution. The deformation error was lower than 8%, meeting engineering requirements. Moreover, the results of different working conditions can achieve a similar relative error of displacement for an identical position. The easy storage of the displacement mapping matrix and the convenience of the boundary information transformation among all substructure levels are prominent aspects. As a result, there is a solid foundation for addressing the time-dependent problem in spite of the simultaneity and region. [ABSTRACT FROM AUTHOR]

Overloaded traffic is one of the major effects that cause more early damage to asphalt pavement than regular traffic. Moving overloaded traffic not only needs to consider dynamic coefficient and axle load coefficient when carrying out pavement mechanics calculations, but also accelerates pavement failure and boosts the cost of construction and maintenance. Although asphalt pavement of a stabilized base with inorganic binder has a strong bearing capacity, the shortcoming of reflective cracking also seriously restricts its performance. This paper describes the mechanical response and crack propagation of asphalt pavement of stabilized base with inorganic binder which has a crack, under the coupling effect of moving overloaded traffic and temperature. Extended finite-element method (XFEM) was conducted to simulate reflective cracks propagating freely from a stabilized base with inorganic binder to asphalt overlay. Dynamic analysis was also carried out by varying the axle weight and tire pressure, which could help highway builders understand the stress distribution of pavement under design traffic and the crack propagation law of pavement structures. Results indicated that the mechanical response of asphalt pavement was comprehensively related to tire pressure, axial weight, and its active position and that overloaded traffic accelerates crack propagation more than regular traffic. This research achievement contributes to providing roadway engineers with a more profound perception to potentially advance pavement design practitioners for specific traffic characteristics. [ABSTRACT FROM AUTHOR]

As the second-generation high-temperature superconducting conductors, rare earth–barium–copper–oxide (REBCO) coated conductor (CC) tapes have good potential as high-field and high-energy superconductors. In superconducting applications, several joints are required for conjugating comparatively short REBCO CC tapes. Soldering lap joints are the simplest and most commonly applied REBCO CC joints. In addition to joint resistance, the mechanical behavior and electromechanical properties are also crucial for superconducting applications. In this paper, the electromechanical properties and mechanical behaviors of soldering lap joints at 77 K under a self-field were studied. The mechanical behavior was addressed by using a full three-dimensional multilayer elastic–plastic finite element model (FEM) with REBCO CC tape main layers and solder connecting layers. Then, the electromechanical properties were analyzed by using Gao's strain- I c degradation general model on the basis of the FEM results. Both the mechanical behavior and electromechanical properties were verified by experimental results. The effects of soldering lap conditions including lap length, soldering thickness and lap style on the electromechanical properties and mechanical behaviors were discussed. The results indicate that shorter overlap lengths and a thinner solder can reduce the premature degradation of Ic due to stress concentrations nearby the joint edges; moreover, the irreversible critical strain is significantly higher in the back-to-back joint approach compared to the widely used face-to-face joint approach. [ABSTRACT FROM AUTHOR]

An SHS-CFSHS X-joint is fabricated by welding two square hollow section (SHS) braces to a concrete-filled square hollow section (CFSHS) chord. In this paper, the stress concentration factors (SCFs) of SHS-CFSHS X-joints are investigated through experimental tests and finite element analysis (FEA), with the hot spot stress method serving as the analytical approach. Eight specimens are designed and manufactured, with FE models built in software ANSYS. These FE models are validated against the test results. The specimens are tested under brace axial tension to determine the SCFs of the X-joints. It shows that the concrete filled in the chord effectively reduces the SCFs of the X-joints. To further explore various load conditions and the influence of the parameters, FEA is carried out and a total of 64 FE models are built. Based on the FEA results, multiple regression analysis is used to obtain the SCF formulae of SHS-CFSHS X-joints under axial tension load and in-plane bending load in the brace, respectively. Comparison and analysis of the SCF results obtained from experimental tests, the proposed formulae, and FE simulations reveal that the formulae presented in this study are both conservative and suitable for predicting SCFs. [ABSTRACT FROM AUTHOR]

Tubular joints are important connecting parts of a welded steel tube structure. The S-N curves based on the hot spot stress (HSS) method are often used to evaluate the fatigue life of tubular joints in practical engineering. The stress concentration factor (SCF) is a key parameter to calculate HSS. In this paper, stress concentration tests of hollow-section and concrete-filled double-skin tubular (CFDST) K-joints were carried out, respectively, and then finite element models of K-joints considering the weld were established. The developed models were validated with the experimental results. The influence of key geometrical parameters, such as the diameter ratio of brace to chord β, the diameter to thickness ratio of chord γ, the wall thickness ratio of brace to chord τ, brace angle θ, and hollow section ratio ζ on the distribution and key position of SCFs along the weld toe, was discussed. Parametric studies were conducted to obtain the calculating equations for the SCF values of CFDST K-joints. The results demonstrate that infill concrete can effectively reduce SCFs along the weld on the chord. When the hollow section ratio was reduced to 0.317, the SCF was reduced by 77.2%. Notably, the SCF reduction rate was sensitive to γ and θ, with a decrease observed as γ increased. The hollow section ratio ζ had a less pronounced effect on SCF distribution patterns, but as ζ decreased, the chord's stiffness improved, suggesting a potential approach to enhance joint performance. The distribution of SCFs is similar for joints of the same type but different geometric configurations. The innovatively integrated hollow section ratio in the CFDST design equation significantly simplifies and enhances the precision of SCF calculations for CFDST K-joints. [ABSTRACT FROM AUTHOR]

Microcomponent manipulation (MCM) technology plays a decisive role in assembling complex systems at the micro- and nanoscale. However, the existing micromanipulation methods are difficult to widely apply in the manufacturing of microelectromechanical systems (MEMSs) due to the limited manipulation space and complex application objects, and the manipulation efficiency is relatively low, which makes it difficult to industrialize these micromanipulating systems. To solve the above problems, this paper proposes an efficient metal MCM strategy based on the electrochemical method. To verify the feasibility and repeatability of the strategy, the finite element model (FEM) incorporating the hydrodynamic and electrochemical theories is used to calculate the local stress distribution of the contact position during the dynamic pick-up process. Based on the simulation results, we defined the relationship between the parameters, such as the optimal manipulating position and angle for picking, transferring and releasing. The failure behaviors of pick-up are built to realize the efficient three-dimensional manipulation of microcopper wire of 300 μm. By establishing a theoretical model and experimental verification, it was concluded that the middle point was the best manipulating position when picking up the microcopper wire, the most efficient picking angle was between 45 and 60 degrees for the pipette, and the average time was 480 s in three sets of picking–release manipulation experiments. This paper provides an achievable idea for different types of micro-object manipulations and promotes the rapid application of micromanipulation techniques in MEMSs. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to investigate the effect of microtextured tools on the geometric morphology of serrated chips, and further improve the cutting performance of polycrystalline cubic boron nitride (PCBN) tool and extend the tool life and the surface quality of the machined surface. Design/methodology/approach: A three-dimensional finite element cutting model of hardened steel AISI D2 with microtextured PCBN tools were established using the finite element software Abaqus, and cutting tests were carried out. Furthermore, the stress distribution in the primary deformation zone was investigated based on the triaxiality of stress, and the influence of microtexture on the geometric morphology of serrated chips and crack development was researched. Findings: The results show that compared with nontexture tools, elliptical pits and wavy grooves microtexture tools have lower serrated degree Gs, higher serrated frequency f per unit length and more miniature serrated step Pc. The serrated phenomenon is intensified because the tensile stress zone of chips generated by nontextured tools is longer than that of elliptic pits and wavy grooves microtexture tools. Simultaneously, the maximum value of triaxiality in the tensile stress zone achieved by nontexture tools is larger than that of the two microtexture tools, and chips obtained by nontextured tools are more susceptible to propagation fractures. Originality/value: This paper mainly studies the effect of microtexture on chip microgeometry, which is relatively little studied at present. At the same time, this paper has a certain engineering significance for PCBN tool turning hardening steel. Peer review: The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2023-0149/ [ABSTRACT FROM AUTHOR]

The reliability of the aircraft engine duct system is of paramount importance as it directly affects the safety of the aircraft, particularly under high-temperature and high-pressure cycles. In this study, ANSYS Workbench was used for finite element analysis, and a sleeve-type tie rod structure was proposed to address the critical problem of tie rod tearing during the operation of the duct system, thereby optimizing thermal stress compensation for the duct system. The research results show the following: (1) The anchor of the traditional tie rod imposes displacement constraints on the thermal deformation of the duct system, leading to stress concentration and even structural failure in the connection area between a duct and a tie rod. (2) The improved sleeve-type tie rod provides greater axial displacement freedom for the duct, effectively mitigating stress concentration phenomena. (3) Taking a worst-case scenario of 537.78 °C and 2 MPa as an example, the sleeve-type tie rod proposed in this paper can reduce the stress at the tie rod connection from 757.61 MPa to less than 25 MPa, a reduction of more than 96%. The original tie rod tearing problem is solved, and the maximum stress of the whole duct system is reduced to 459.25 MPa, which is below the yield strength. [ABSTRACT FROM AUTHOR]

In recent years, reinforced thermoplastic composite pipe (RTP) is widely sought after because of its high strength and corrosion resistance. The development of a connector that is easy to install and highly reliable is essential for the successful application of RTP. In this paper, the mechanical properties of a butt-welding armoured joint between composite pipes were investigated by theoretical calculation method and finite element method. A plane strain model was established to study the mechanical response of the joint under internal pressure. In order to verify the theoretical results, a finite element model was established to analyse the stress distribution of the joint. Moreover, the finite element results are in good agreement with the theoretical results. The research of this paper provides a valuable reference for the engineering application of the joint in the pipeline system. [ABSTRACT FROM AUTHOR]

This paper proposes a reinforced concrete (RC) boundary beam-wall system that requires less construction material and a smaller floor height compared to the conventional RC transfer girder system. The structural performance of this system subjected to axial compression was evaluated by performing a structural test on four specimens of 1/2 scale. In addition, three-dimensional nonlinear finite element analysis was also performed to verify the effectiveness of the boundary beam-wall system. Three test parameters such as the lower wall length-to-upper wall length ratio, lower wall thickness, and stirrup details of the lower wall were considered. The load-displacement curve was plotted for each specimen and its failure mode was identified. The test results showed that decrease in the lower wall length-to-upper wall length ratio significantly reduced the peak strength of the boundary beam-wall system and difference in upper and lower wall thicknesses resulted in lateral bending caused by eccentricity in the out-of-plane direction. Additionally, incorporating cross-ties and reducing stirrup spacing in the lower wall significantly improved initial stiffness and peak strength, effectively minimizing stress concentration. [ABSTRACT FROM AUTHOR]

Traditional coiled tubing radial drilling with the same diameter cannot support deep and ultra-deep wells for high-pressure hydraulic jet drilling due to small diameter and sizeable hydraulic loss over long distances. The novel downhole movable pipe radial hydraulic drilling technique extracts a small diameter high-pressure injection pipe from the (tubing pipe) oil pipe and then drills it horizontally into the formation to form a radial hole. Dynamic sealing is the core of this technology, which achieves high-pressure fluid sealing while ensuring the injection pipe smoothly slides out of the oil pipe. A sealing tool is designed between the tubing and the injection pipe to prevent the leakage of high-pressure fluid. In this paper, the finite element model of the sealing tool was established, and the deformation and stress of the sealing tool under different interference and fluid pressure were simulated and analyzed. The relationship between stress distribution and contact pressure under the corresponding conditions was obtained. The results show that the von Mises stress increases significantly with the increase in fluid pressure under certain interference conditions. When the fluid pressure was 35 MPa, 52 MPa, and 70 MPa, the maximum von Mises stress was 29.65 MPa, 30.87 MPa, and 32.47 MPa, respectively, within a reasonable range. The stress peak area changes simultaneously, indicating that the possible damage location changes with the fluid pressure change. The maximum contact pressure between the sealing ring and the smooth rod increases with interference and fluid pressure, which always meets the sealing conditions. A laboratory test bench was built to test the high-pressure sealing performance of the sealing tool. Combined with the simulation data and test results, the downhole continuous rod dynamic sealing tool was modified to provide theoretical guidance for practical application. [ABSTRACT FROM AUTHOR]

Currently, in some domestic and foreign mines, the backfill drilling pipeline experiences a rupture phenomenon even when the wear degree is low. This results in a delay in production due to the filling becoming 'sick'. This paper presents, for the first time, the damage mechanism from a mechanical perspective and re-derives the anti-extrusion strength model of the backfill drilling pipeline. We investigate the influence of the law on the anti-extrusion strength of pipelines from the perspective of strata and cement rings. We then verify the theoretical and simulation results through engineering examples. The results demonstrate that the Mises stress criterion is a suitable modification principle for the anti-extrusion strength model of the backfill drilling pipeline. The anti-extrusion strength of the pipeline is related to the elastic modulus and Poisson's ratio of the stratum, and the thickness of the cement ring. It is negatively affected by the depth of the stratum. For hard strata, a cement ring with a smaller elastic modulus is suitable, while for soft stratum, a cement ring with a larger elastic modulus is recommended. When the missing angle of the cement ring is less than 60°, the stress concentration factor increases up to 2.2. The stress unloading capacity of the cement ring ranges from 32.7% to 37.8%, and optimal performance of the cement ring is achieved when it has high strength and low rigidity. The backfill filling pipeline of a copper mine abroad was destroyed due to external extrusion force exceeding its anti-extrusion strength value. The modified pipeline anti-extrusion strength model is 18.2% higher than the pipeline API strength value. This finding can inform the design of the backfill filling pipeline for China's kilometer-deep wells in the future. [ABSTRACT FROM AUTHOR]

This paper introduces a highly efficient computational approach using the extended finite element method to model three-dimensional mechanics of holes and voids. The defect is encapsulated within a single element with a tailored exponential enrichment function that captures the behavior near the discontinuity boundary and can account for the pressure acting on the void's surface through an equivalent nodal force vector. The method's results were compared against analytical solutions and conventional finite element method results for problems involving single and multiple holes. The comparison demonstrated that the method provides accurate stress concentration estimates while adhering to computational constraints. [ABSTRACT FROM AUTHOR]

Patching is a common technology used in repairing asphalt-pavement potholes. Due to the differences in material properties between patched- and unpatched-asphalt mixtures, significant strain and stress concentrations could be induced; thus, further cracks and interfacial debonding distress could be caused. As a remedy, the strain and stress concentrations can be alleviated by utilizing optimum patching shapes. Therefore, this paper employed finite element methods (FEM) to deeply analyze the mechanical performance of patched-asphalt pavements embedded with different patching shapes. Three patching shapes, these being rectangular, stair, and trapezoid, were considered for use in pavement pothole repairs based on two- and three-dimensional finite element models. In the two-dimensional models, Top-Down and Bottom-Up crack propagations were simulated to assess the anti-damage performance of the patched pavements with different patching shapes. In addition, the thermal stress behaviors within patched-asphalt pavements were simulated using the two-dimensional model to analyze the performance of the patched pavements during the cooling process in construction. In addition, interface-debonding performance was simulated for the patched-asphalt pavements using three-dimensional models. In light of the simulation results, engineers are expected to better understand the mechanism within patched pavements and to improve the quality of the pavement patching. [ABSTRACT FROM AUTHOR]

The Hollow Cylindrical Roller Bearings (HCRBs) have some important advantages over solid cylindrical roller bearings such as low weight, good lubrication capability and high bearing stiffness. Additionally, it's also known that maximum contact stress value between the roller and race is less in hollow cylindrical roller bearings compared to solid cylindrical roller bearings. In this paper, the effect of roller's hollow size in Hollow Cylindrical Roller Bearing under a radial load on the maximum contact stress value and contact stress distribution is studied by using finite element method. The maximum tangential tensile stress occurring on the inner surface of the hollow roller is also investigated. Moreover, the effect of the penetration amount, which is a critical parameter for a nonlinear contact problem such as roller-race contact, on the contact stress is taken into consideration, as well. It's seen from the results that tangential tensile stress on the inner surface of the hollow roller has an effect on the value of optimum hollow size. Besides, it is deduced from results that the penetration amount between the contacting surfaces have considerable influence on the contact stresses and it should be taken into consideration when analyzing the roller-race contact problem by using finite element method. [ABSTRACT FROM AUTHOR]

This paper deals with the problem of stress concentration at the weld toe of non-load-carrying-type plate cruciform joints under tension, bending, and shear. Theoretical stress concentration factors were derived using the finite element method. Five of the most important geometrical parameters: the thickness of the main plate and the attachments, the weld throat thickness, the weld toe radius, and the weld face inclination angle were treated as independent variables. For each loading mode—tension, bending, and shear—parametric expression of high accuracy was obtained, covering the range used in real structures for cruciform connections. The maximum percentage error was lower than 2.5% as compared to numerical values. The presented solutions proved to be valid for the toe radius ρ tending to zero. [ABSTRACT FROM AUTHOR]

This paper aims to assess the mechanical characteristics of the orthotropic steel deck (OSD) in heavy-haul railway bridges. Taking the Dongting Lake Bridge as an example, to simulate the transfer effect of the track structure and get mechanical characteristics of the OSD under the service load, the refined segmental finite element model (FEM) of the OSD in a heavy-haul railway bridge was established. Moreover, the Chinese C80 heavy-haul train (the C80) was selected as the applied load to make the analysis results close to the actual situation. And then, the stress influence lines of critical components in OSD were analyzed. Notches at diaphragms of the OSD are more likely to produce stress concentration. Due to the dense distribution and high stiffness of the longitudinal ribs of OSD, the final load influence range of OSD is limited. Since the T-shaped longitudinal ribs (T-Ribs) are located under the position of each rail, and its stiffness is greater than the adjacent U-shaped longitudinal ribs (U-Ribs), so that the T-Ribs are important load-bearing components of the OSD in heavy-haul railway bridges. Furthermore, the influences of the stiffness ratio of T-Rib to U-Rib on the mechanical characteristics of the OSD were analyzed. [ABSTRACT FROM AUTHOR]

This paper presents a novel connecting plate for achieving a flexible connection in a soft manipulator. The main material used in the connecting plate is silicone, which functions similarly to the bionic oblique muscle (BOM) of an octopus arm and takes over the two actuator segments. Each segment of the actuator consists of three chambers, and the chambers are assembled with the connecting plate via bolts and loops to be a manipulator. By using a flexible plate instead of a rigid one, the manipulator achieves more dexterous movements. This paper establishes a nonlinear model for analyzing the shear and compression deformation of a silicone connecting plate. Additionally, finite element method was used to analyze the mechanical performance of the connecting plate. The deformation of a soft material can reduce the stress concentration during movement of the manipulator. Therefore, in the experiment, the BOM exhibited better motion performance compared with the rigid connection plate. [ABSTRACT FROM AUTHOR]

The paper presents the proposal of a leakage prediction method in flange joints, after pipeline deformation, based on FEM (Finite Element Methods). The stages of developing the design are discussed, and a complex, multi-stage method of applying the loads is presented in detail. Moreover, the gasket material data obtained in experiments were used. The paper also presents the results of calculations on a non-uniform stress distribution in the radial direction of the gasket. In addition, it has been shown that the deflection of the pipeline with a minor displacement causes an increase in the diversification of the circumferential pressure of the gasket, and also has a significant influence on the determination of the actual state of stress to which the gasket is subject. Moreover, it was found that the distribution of contact pressure on the deflection of the pipeline has a significant influence on the level of leakage. The results of tests are compared to the results of the numerical calculations of the stress in bolts. By comparing the bolt tension changes obtained by numerical and experiment analyses, it has been shown that the assumptions made in developing the numerical model are correct. [ABSTRACT FROM AUTHOR]

BACKGROUND: Although the internal fixation technique for scoliosis is effective, there is a great risk of nail placement in actual operation. OBJECTIVE: To compare the effects of three different nail placement strategies on LenkeC patients with scoliosis under cyclic loading. METHODS: Firstly, the finite element model was established by using CT scanning images and X-ray images of patients with LenkeC scoliosis. Secondly, the validity of the model was verified. Finally, the harmonic response analysis and transient dynamic analysis were carried out. Results: The results showed that the maximum amplitude of each vertebral body appeared in the Z direction at the third natural frequency and the amplitudes of each corresponding vertebral body were very close under three kinds of nail placement. Under different nail placement methods, the uneven distribution of nails would make the model produce obvious stress concentration, but the principal stress of vertebral body and nail rod was far lower than its own yield strength. This showed that under the axial cyclic load, the vertebral bodies of scoliosis tended to have larger impact in Z direction. From the point of view of dynamics, it was feasible to reduce a certain number of nails in operation. CONCLUSION: This paper revealed that it was feasible to reduce a certain number of nails during surgery. [ABSTRACT FROM AUTHOR]

OLEDs have become a promising candidate for flexible displays. It is obvious that the requirements on the mechanical property of a flexible OLED screen are higher than common OLED displays. However, with a stacked structure and a complicated property of optically clear adhesive (OCA), it is very difficult to theoretically compute or experimentally measure the stress and strain distributions on each layer during the bending process. The paper employs finite element analysis to evaluate the bending property of a flexible OLED screen. For common U‐shaped bending, the maximum stress increases rapidly as the bending radius decreases. For small bending radius, the water‐drop‐shaped mode presents higher structure reliability than U‐shaped bending. [ABSTRACT FROM AUTHOR]

Compared with the traditional connection (bonding and bolting), the hybrid connection has attracted increasing attention in various fields for its better mechanical properties. Some research demonstrates that providing preload, a necessary condition for bolted connection increases the strength of the conventional bolted joint. However, those research depends on the test procedure, and there are few studies on the mixed joint. In this paper, we studied the tensile behavior of CFRP（carbon‐fiber‐reinforced‐polymer)/titanium alloy multi‐bolt hybrid bonded/bolted (HBB) joints under preload with multiple parameters, such as the size of preload, the number of bolts, and the way of connection. A finite element model of joint strength prediction under preload based on the 3D Hashin failure criterion was established and combined with experimental verification. This work reveals that: The preload can effectively reduce the stress concentration around the bolt hole of CFRP laminate and enhance the strength of the mechanically fastened joints. As for the HBB joint, the simulation results of the scalar stiffness degradation (SDEG) of the adhesive layer indicate that the application of preload can also effectively slow down the failure process of the joint and has a significant impact on the strength of the joint. However, for the single‐bearing full‐thread bolted joint, the sizeable preloading force will lead to the extrusion deformation of the bolt thread and screw, and excessive preloading may even lead to the shear failure of the bolt. [ABSTRACT FROM AUTHOR]

A finite element model (FEM) of the bracket arm of wrecker is developed and the mechanical behavior under six representative conditions is studied in this paper. Stress test experiment is carried out to validate the presented FEM. Comparison analyses show that results predicted from the FEM are in good agreement with those obtained from the test experiment. Moreover, the mechanical behavior analyses also give the danger working conditions for each component of the bracket arm. Based on the stress distributions under the danger working condition, structural improvement is conducted for the component which is prone to material failure. Mechanical behavior analyses of the improved structures are also carried out in this paper. Numerical analysis results show that the maximum stresses of each improved component of the bracket arm are all reduced to close or below the allowable stress. This indicted that the load bearing capacities of each component are improved effectively and meet the requirements of engineering applications. [ABSTRACT FROM AUTHOR]

This paper presents a novel design and control strategies for a parallel two degrees-of-freedom (DOF) flexure-based micropositioning stage for large-range manipulation applications. The motion-guiding beam utilizes a compound hybrid compliant prismatic joint (CHCPJ) composed of corrugated and leaf flexures, ensuring increased compliance in primary directions and optimal stress distribution with minimal longitudinal length. Additionally, a four-beam parallelogram compliant prismatic joint (4BPCPJ) is used to improve the motion decoupling performance by increasing the off-axis to primary stiffness ratio. The mechanism's output compliance and dynamic characteristics are analyzed using the compliance matrix method and Lagrange approach, respectively. The accuracy of the analysis is verified through finite element analysis (FEA) simulation. In order to examine the mechanism performance, a laser interferometer-based experimental setup is established. In addition, a linear active disturbance rejection control (LADRC) is developed to enhance the motion quality. Experimental results illustrate that the mechanism has the capability to provide a range of 2.5 mm and a resolution of 0.4 μm in both the X and Y axes. Furthermore, the developed stage has improved trajectory tracking and disturbance rejection capabilities. [ABSTRACT FROM AUTHOR]

Introduction: The design of high-pressure optical windows is one of the key tasks in deep-sea exploration, as it directly determines the reliability and maximum operating depth of underwater optical equipment. Method: In this paper, mechanical modeling and finite element analysis methods are employed to study optical windows. Results and discussion: Results show that changes in boundary conditions during loading significantly affect the stress distribution of the window. Based on this conclusion, an optimization design method is proposed, which involves the use of transition materials to reduce the impact of base deformation on the window. The study further analyzes the effects of the transition material's Young's modulus, Poisson's ratio, thickness, and friction coefficient on the stress of the optical window. A calculation method for material selection criteria is proposed to select appropriate transition materials, and actual materials are used for verification. Finally, the reliability of the optimization design scheme based on transition materials is confirmed through highpressure experiments. [ABSTRACT FROM AUTHOR]

The present paper aimed to study the effect of the hole on the stress distribution and stress intensity factor of the mode I fracture in a perforated plate with an edge crack. For this purpose, a plate with an edge crack and one or two holes near the crack tip is investigated. First, the cracked plate without a hole was analysed with Abaqus software, and the results were validated through Westergaard's analytical method. Then, a plate with an edge crack and one or two holes near the crack tip was also analysed with Abaqus software. The effects of the distance between the hole and the crack tip, as well as the radii of the holes on the stress distribution σy and stress intensity factor KI were also investigated. The findings indicated that making a hole in the plate significantly reduces the amounts of the stress and stress intensity factor at the crack tip if the hole has an appropriate radius and position relative to the crack tip. [ABSTRACT FROM AUTHOR]