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This document is a compilation of various research papers and articles that discuss the use of machine learning and other techniques to predict fatigue lifetimes in different materials and structures. The papers cover topics such as the use of neural networks, XGBoost, and physics-informed machine learning models for fatigue prediction. The research focuses on different materials, including aluminum alloys and lead-free solders, and explores the effects of factors such as wear, lubrication, corrosion, and stress on fatigue life. The papers provide insights into the application of machine learning techniques in predicting fatigue lifetime and offer potential solutions for improving the accuracy of these predictions. [Extracted from the article]

This document is a reference list for a research paper on fracture mechanics and structural integrity. The paper explores the effect of element size on fracture propagation stress using energy criteria. The research was funded by the Ministry of Higher Education Malaysia. The document also includes a Python code for an artificial neural network algorithm used in the research. The reference list contains other research papers on fracture mechanics, machine learning, and structural integrity. [Extracted from the article]

This document provides a comprehensive overview of the integration of civil structural health monitoring and machine learning in the field of concrete structures. It discusses the importance of monitoring infrastructure condition and the challenges of manual inspection. The document highlights the increasing use of machine learning algorithms, such as computer vision methods, in optimizing maintenance and repairs. It presents case studies and applications of machine learning in civil engineering, including damage detection and load assessment. The document also emphasizes the challenges and limitations of using machine learning in this context and recommends further research and interdisciplinary collaboration. Additionally, it addresses ethical and privacy concerns, the importance of open data sharing, and aligning machine learning applications with sustainability efforts. The document includes a list of academic articles related to machine learning techniques in concrete structures, covering topics such as crack detection and structural health monitoring. It also compiles various studies and research papers on machine learning for structural health monitoring in concrete structures, exploring different methods and highlighting the potential of deep learning models and image processing techniques for crack detection. Overall, the document provides a comprehensive overview of the application of machine learning in the field of structural health monitoring for concrete structures. [Extracted from the article]

This document provides a list of references to research papers and articles related to machining techniques and optimization for specific materials like Inconel 718. The papers cover various topics such as tool wear reduction, the use of nanofluids in machining, multi-objective optimization, and the application of machine learning algorithms. These references offer diverse perspectives and approaches to the subject matter, making them valuable resources for library patrons conducting research on these topics. [Extracted from the article]

This article explores the phenomenon of ignition and explosion in high-entropy alloys (HEAs) under compression. The study focuses on specific HEAs in the Ti-Zr-Hf-Ni-Cu and Ti-Zr-Hf-Ni-Cu-Co systems, which exhibit high strength and ductility. The authors propose a model to explain the ignition and explosion, which occurs when certain critical levels of strength and ductility are reached. The article provides detailed information on the materials and methods used in the study, as well as the chemical composition and physical properties of the alloys. Additionally, the text discusses the mechanical testing and failure process of a specific alloy, highlighting the factors that contribute to ignition and explosive failure. The research was funded by the National Academy of Sciences of Ukraine and includes a list of references to related scientific articles and papers. [Extracted from the article]

This article discusses the use of Additive Manufacturing (AM) in automotive engineering, specifically focusing on the reliability of AM for advanced powertrain components. The study evaluates the mechanical behavior and microstructure features of samples made of AM 17-4PH steel, including engine exhausts, drive shafts, gearbox components, braking systems, and conrods. The researchers analyze the effects of sample geometry, size, and heat treatments on the properties of the samples. The study aims to provide insights for designing efficient prototypes using AM alloys and technology. The article also includes a list of references to other research papers and theses related to the fabrication and properties of stainless steel using AM techniques, providing valuable insights for researchers and engineers in the field. [Extracted from the article]

The article discusses the use of Structural Health Monitoring (SHM) techniques to ensure the safety and longevity of civil infrastructure. It focuses on damage identification methodologies and the use of numerical models to simulate the behavior of concrete structures under different fracture conditions. The article emphasizes the importance of accurate numerical strategies and comprehensive analysis of existing structures. It also presents the results of studies on the degradation of natural vibration frequencies and the detection of damage in plain concrete structures. Additionally, the article provides a compilation of research articles covering various topics related to vibration-based damage detection and structural health monitoring. Lastly, it includes a list of references cited in a research paper on the degradation of vibration characteristics in reinforced concrete beams and micro-fracture instabilities in granular solids. [Extracted from the article]

This article discusses a numerical investigation of an extra-deep drawing process using industrial parameters. The study focuses on the formability analysis and process optimization of the drawing process. The authors conducted experiments and simulations to understand the factors that contribute to defects such as rupture and wrinkling in the manufacturing process. They used numerical modeling and measurements to analyze the behavior of the materials and optimize the process parameters. The study provides valuable insights for manufacturers in various industries, including household appliances and automobile construction, to improve the quality and competitiveness of their products. Additionally, there is a document that provides a list of references cited in a research paper on the behavior and processes of deep drawing sheet metal. The references cover various aspects of deep drawing, such as material limits, thinning, wrinkling, spring-back, cracking prevention, lubricants, tribological behavior, and optimization of process parameters. This comprehensive list of sources can be explored by library patrons for further information on these topics. [Extracted from the article]

In recent years, 3D printing technology has assumed an important role in advanced construction processes across various engineering fields. Among these, the application to the architectural restoration of historic structures is particularly fascinating. The ability to precisely reproduce the shape and surface details of complex elements, combined with the availability of a wide range of printing materials, makes 3D printing technology competitive compared to traditional techniques. In this context, the internal volume structure of 3D printed elements represents an additional design parameter to consider for enhancing interventions in terms of reducing the required material, and thus, lowering costs and environmental impact. The paper presents the outcomes of experimental tests and numerical analyses conducted on plates, which represent portions of more complex elements produced by using Additive Manufacturing (AM) technology. These plates feature various internal configurations (such as reticular and rhomboidal patterns) derived from a mono-objective design optimization process. The experimental tests aim to analyze the influence of the configuration and the pattern on the behavior of printed samples. Additionally, the paper discusses insights derived from both theoretical models and Finite Element analyses, providing a clearer understanding of the experimental results.

This article discusses an experimental study and mathematical modeling of face milling forces on high-strength, high-viscosity shipbuilding steel. The study focuses on preparing edges of holes in ship hull structures for welding, proposing the use of non-stationary technological complexes (NTC) with numerical control for machining complex surfaces. The article presents a mathematical model of the milling forces and discusses challenges and potential solutions for machining high-strength steel. The findings aim to contribute to the development of special equipment for processing hull structures under non-stationary conditions. This article provides valuable insights into tool design in Russian engineering, making it a valuable resource for library patrons interested in advancements and innovations in this field. [Extracted from the article]

This document discusses the determination of residual stress in aluminum alloy aerospace components using the blind hole drilling method and optical interferometric measurements. The study presents experimental procedures and uncertainty analysis for measuring residual stresses in materials. The results show that the method provides accurate and reliable results with a low level of uncertainty. The document also provides a list of references related to the measurement of residual stresses, discussing various methods and their applications in different fields. [Extracted from the article]

This article presents an experimental investigation on the fatigue and fracture properties of R350HT rail steel. The study aims to improve the strength, toughness, and wear resistance of railway steels. Various tests were conducted to quantify the fracture mechanics properties of the steel, including tensile tests, fatigue crack growth rate tests, and plane strain fracture toughness tests. The results provide valuable information for assessing the damage tolerance of railway rails and further developing rail steels. The findings suggest that R350HT steel has similar properties to other pearlitic rail steels but may have lower damage tolerance. [Extracted from the article]

This document is a compilation of research articles that discuss various methods for measuring and analyzing stress intensity factors (SIF) in fracture mechanics. The articles cover topics such as digital image correlation, finite element processing, and the effects of material properties on fracture behavior. They provide valuable insights and findings for researchers and engineers studying fracture mechanics and its applications. [Extracted from the article]

This article discusses the effectiveness of partially wrapping stainless-steel wire mesh (SSWM) on the compression behavior of concrete cylinders. The study aims to understand the behavior of partially SSWM-confined concrete and investigate the axial compressive strength and strain behavior of both the wrapped and unwrapped regions of the concrete cylinder. The study proposes an effective confinement coefficient for estimating the compressive strength of partially SSWM-confined concrete. Additionally, the article includes a list of references related to the compressive behavior of concrete confined by various materials and reinforcement methods. The calculations provided in the document show that SSWM can increase the compressive strength of concrete by 18.38%. [Extracted from the article]

This article explores the behavior of short beam specimens made from a titanium/fiber-reinforced polymer (FRP) hybrid sandwich material. The study compares the flexural characteristics of specimens with FRP skins and titanium skins, which were manufactured using additive manufacturing processes. Three-point bending tests were conducted to evaluate the mechanical properties of the specimens. The results provide insights into the fracture mechanisms and performance of the hybrid sandwich material. The study found that titanium-skinned specimens had the highest strength, while aramid and carbon fiber skins had comparable mechanical characteristics. The article also includes micrographs of the fracture surfaces and compares the performance indexes of the different specimens. [Extracted from the article]

This paper proposes a methodology to evaluate and optimize the dynamic response of tall buildings under wind loading, controlled through semi-active Magneto-Rheological dampers (MR dampers). For this, a tall building, modeled as a 2D frame, is taken as case study and three structural control configurations are proposed. The original structural configuration of the building is the first configuration analyzed, called Uncontrolled Original (C1). In the second configuration, called Uncontrolled Optimized (C2), the fundamental frequency of the building is optimized via PSO algorithm as a function of its mass. Then, in the third configuration, Controlled Optimized (C3), a set of MR dampers with behavior formulated via the modified Bouc-Wen rheological model and controlled through the Linear Quadratic Regulator associated with the Clipped Optimal control strategy (LQR-CO) is applied to the structure. Finally, the dynamic response of the three scenarios under wind action is analyzed and compared to performance criteria established in the literature. The results demonstrate that the C3 configuration is the only one able of satisfying all the established performance criteria, proving that the proposed methodology y that combines structural optimization with MR dampers is a powerful tool for vibration control.

Partial confinement can provide sufficient reinforcement to enhance the compressive strength and ductility of concrete with lesser confining material. This paper presents the results of an axial compression test conducted on eighteen plain concrete cylinders of 150 mm diameter and 300 mm height partially confined with a Stainless-Steel Wire Mesh (SSWM) strip of different widths. The study included two specimens without wrapping, two fully wrapped specimens, and others wrapped with two SSWM strips of varying widths at both the ends of concrete cylinder. The strain on SSWM up to failure is measured to understand the effectiveness of lateral confining pressure on the behaviour of concrete cylinders. The peak axial compressive strength and corresponding strain of unconfined and SSWM-confined concrete cylinders are compared. The result shows a significant increase in peak confined compressive stress as compared to an unconfined concrete cylinder. However, the confinement efficiency is reduced when the height of the unconfined region exceeds the diameter of the cylinder, and significant strain localisation is detected within the unwrapped region. Based on experimental investigation, a confinement coefficient is suggested for a partial wrapping of SSWM on the concrete cylinder.

Most techniques of measuring the stress intensity factor (SIF) in the cracking process assume a crack in a planar medium. Currently, there is no effective approach for curved brittle shells, particularly for non-developable cases, i.e., shapes with non-vanishing Gaussian curvature. This paper introduces a novel approach to obtaining material properties related to fracture by experimentally observing weakly curved surfaces. Based on the DIC record of the displacement field around the crack tip, the truncated Williams expansion is fitted to the data adjusted according to the shallow shell equations. The convergence properties of the method are investigated by comparing experimental data of PMMA cylinders to theoretical and numerical predictions. The applicability of the technique to non-developable surfaces is verified. It is demonstrated that robust convergence requires the number of terms in the Williams expansion exceeding 6. For different geometries, the ratio of the data selection radius and the length of the crack should exceed 0.3.

The use of miniaturized specimen testing methods is a promising way to solve the problem of limited materials in RPV monitoring programs. The use of miniature specimens allows the evaluation of fracture toughness from other specimen materials used. In particular, the small-size compact tensile test specimen (0.16T CT) is promising for the determination of fracture toughness, as it can be produced from the standard size Charpy specimen that has already been tested. However, if we have only 0.16T CT test, we cannot investigate the dimensional response and also have only one restricted deformation state, which may pose problems in verifying geometry independence and determining local parameters for state-of-the-art analyses. It is therefore recommended to prepare at least two tests with two different restricted deformation specimens. Therefore, the testing of mini single edge notched bending (SENB) is also required and can be worked out from the Charpy specimens. The paper presents the determination of fracture toughness for these miniaturized specimens by modifying the virtual crack closure technique (VCCT) simulation method using GTN parameters instead of energy release as the driving force. This allows the calculation of the J-integral to proceed in parallel with the crack propagation

The escalating importance of lightweight design in engineering demands innovative strategies to tackle this challenge. Traditionally, the joining of these materials involves rivets, bolts, or adhesives. However, contemporary manufacturing techniques, such as 3D printing, present the potential to fabricate joints without the necessity for additional binding mechanisms. This paper delves into a promising initiative concerning the joining of multimaterial systems, specifically composites and metals. The fabrication of the metal component of the joint through additive manufacturing (AM) enables the manipulation of surface geometry by incorporating patterned anchors. This, in turn, facilitates the direct co-curing of the composite onto the modified metallic surface. The primary objective is to enhance mechanical interlocking without relying on traditional fastening elements or adhesives. The study evaluates various anchor geometries to assess their efficacy in increasing the overall joint strength. This assessment employs the cohesive zone modeling (CZM) method to simulate joint specimens, followed by comparative analyses to quantify the strengths of the joints

This is the second part of a short three-paper series, aiming to revisit some classical concepts of Linear Elastic Fracture Mechanics. Being the intermediate step of the analysis between infinite domains (discussed in Part-I) and finite bodies (that will be discussed analytically in the third part of the series), the present part offers an alternative theoretical approach for the confrontation of problems dealing with both infinite and finite bodies with geometrical discontinuities. The method is here applied to a stretched, single-edge notched strip. Assuming that the strip is made of a linearly elastic and isotropic material, the complex potentials technique is used. The solution is achieved by extending Mushkelishvili�s procedure, for the confrontation of the prob�lem of an infinite perforated plane. Closed form, full-field formulae are obtained for the stresses all over the notched strip. Using these formulae, the stress concentration factor at the base (tip) of the notch is quantified and studied in terms of the geometrical features of the notch and its dimensions relatively to the respective ones of the strip. The stress distributions plotted along characteristic loci, resemble closely, from a qualitative point of view, the respective ones provided by well-established analytical solutions. Preliminary numerical analyses in progress provide results in very good agreement with those of the present analysis

This paper discusses the application of machine learning techniques, notably artificial neural networks (ANN), in the fracture analysis of semi-infinite elastic plates with edge cracks. The Stress Intensity Factor (SIF) model for a semi-infinite plate with a tip crack is employed in the study, and Finite Element Analysis (FEA) is performed via ABAQUS CAE to build a comprehensive dataset containing numerical simulations data. To improve accuracy and reliability, data preprocessing is implemented, and ANN as a valuable machine learning model is trained with various variables describing crack propagation, stress distribution, and plate structure as input parameters. The suggested method is compared to established fracture analysis methods, proving its accuracy in predicting crack behavior and stress distribution under a variety of loading circumstances. The model provides useful insights into the behavior of edge cracks in semi-infinite elastic plates, enhancing material engineering and structural mechanics. The study demonstrates the potential of combining FEA and machine learning to improve fracture analysis capabilities, and it discusses limitations and future research directions, encouraging the exploration of advanced machine learning techniques and broader fracture scenarios for future fracture mechanics innovation

In this paper, tensile tests of specimens with a pattern of holes made of fiber-glass plastic based on combined epoxy and phenol-formaldehyde resins are carried out in order to study the processes of damage accumulation and tension fracture. The Vic-3D video system is used to evaluate damage development and inhomogeneity of strain localization during loading. Continuous recording of acoustic emission signals is carried out during the tests, resulting in obtaining data on fracture mechanisms in the material. Ranges of peak frequencies are identified. Surface analysis of specimens was carried out using a microscope. A significant reduction in strength occurs due to the presence of a circular hole in the material, although additional holes do not exacerbate this effect. Fracture patterns of specimens with a hole pattern have been analyzed, and different "paths" of fracture have been observed. The comparison of strain fields obtained on the basis of application of three-dimensional digital optical system with the configuration of strain fields constructed as a result of numerical modeling by the finite element method has been carried out. It is found that the strain fields for different open hole patterns are quantitatively and qualitatively similar and identical

The article explores the use of Acoustic Emissions (AE) and Non-Extensive Statistical Mechanics (NESM) to assess structural integrity in non-homogeneous systems. It introduces NESM, which is based on non-additive entropies, and discusses its application in analyzing acoustic activity in non-homogeneous systems. The study focuses on the acoustic activity in restored structural elements of the Temple of Parthenon, revealing similarities to previous studies on homogeneous materials. The article also discusses the use of NESM to analyze the acoustic activity in composite marble specimens under various loading conditions. The results provide insights into the behavior of the specimens and the effectiveness of restoration techniques. The study emphasizes the importance of considering material homogeneity and inhomogeneity in understanding the damage process. [Extracted from the article]

The article explores the ultrasonic welding of lap joints using PEI plates and PEI/CF-fabric prepregs. The authors analyze the structure and mechanical properties of the joints and investigate the impact of different parameters on their formation. They find that the tensile strength of the joints is influenced by the CF-fabric content in the prepregs, with higher content resulting in greater strength. The thickness of the joints also varies depending on the duration of the ultrasonic welding process. The authors conclude that optimizing the parameters can lead to improved functional characteristics of the joints. [Extracted from the article]

The article discusses a research project called "nodularWELD" that investigates the fatigue behavior of welded thick-walled nodular cast iron components used in heavy industry and wind energy turbines. The study examines the effects of local material defects on the lifetime of these components and explores the possibility of repair welding. The research project examines different welding fillers and conducts fatigue tests to assess the usability of repair-welded nodular cast iron. The findings show a reduction in fatigue strength for all materials in the welded condition, with the highest loss observed for EN-GJS-450-18. The research suggests that welding for repair purposes may not be feasible for certain applications. The document also includes a list of nomenclature, references, and acknowledgments to the funding source and project partners. [Extracted from the article]

This article discusses the numerical modeling of fracture processes in elastic-brittle bodies with statistically distributed subregions strength values. The authors propose a boundary value problem formulation and a solution algorithm using the finite element method. The study focuses on the distribution range and stress concentration influence on the fracture process. The results of numerical experiments show the significant influence of finite element properties distribution and stress concentration on the modeling results. The proposed approach considers the strength properties' statistical distribution and can be applied to the fracture modeling of inhomogeneous structures. The article also includes a list of references to various scientific articles related to the modeling and analysis of crack growth and failure behavior in different materials and structures. Additionally, the article titled "Ductile-brittle transition by varying structural size" explores the relationship between structural size and the transition from ductile to brittle behavior in materials. The authors conducted experiments and analyzed the fracture mechanics of different materials to understand how changes in size affect their mechanical properties. The findings suggest that smaller structures tend to exhibit more brittle behavior, while larger structures are more ductile. This research provides valuable insights into the behavior of materials under different conditions and can be useful for engineers and researchers studying fracture mechanics. [Extracted from the article]

This article discusses the use of numerical cohesive zone modeling (CZM) in analyzing self-anchoring additive manufacturing (AM) metal-CFRP joints. The study explores various anchor geometries and their effects on joint strength through numerical analysis using the CZM method. The article also mentions other research in the field of joint configurations, including investigations into mechanical properties, joining processes, fracture toughness, and adhesive characteristics. The authors emphasize the importance of lightweight structures in engineering applications and the need for innovative approaches to achieve durable joint configurations. The document discusses the use of the cohesive zone model (CZM) in analyzing the performance of adhesively bonded joints. The study validates the CZM method through simulations of single lap joints (SLJ) using different adhesives. The results show a correlation between the CZM simulations and experimental parameters, demonstrating the reliability of the methodology. The simulations also reveal that certain anchor geometries and adhesives result in higher failure loads, indicating a more robust joint design. The contact status of the joints is analyzed, and it is observed that complete separation occurs after the propagation of separation passes the second row of anchors. Overall, the CZM proves to be an effective tool for analyzing the performance of adhesively bonded joints. The document discusses the impact of different anchor geometries on joint strength. The study focuses on the assumption that joint failure occurs in cohesive or adhesive mode and aims to identify the optimal geometry for potential cohesive failure. The research evaluates the effectiveness of [Extracted from the article]

This article discusses a method for estimating residual stresses in metal samples produced by additive manufacturing, specifically focusing on steel cylindrical bars produced by laser powder bed fusion (LPBF). The method involves making a partial longitudinal cut in the bar using electrical discharge machining (EDM) and measuring the resulting deflection to assess the contribution of residual stresses. The study combines experimental analysis with numerical simulation using finite element modeling (FEM). The proposed method allows for the estimation of residual stresses in the laboratory without the need for special equipment. The article also provides a list of references that cover various topics related to residual stresses and mechanical properties of additively manufactured stainless steel, which can be useful for further research. [Extracted from the article]

This article explores the use of analytical data and machine learning algorithms to improve the performance of damage repair in thin-walled structures, specifically focusing on composite materials used in aircraft repairs. The authors review previous research on composite repairs and propose the use of machine learning algorithms to enhance repair performance. They conducted an analytical investigation and used regression techniques to approximate the data and improve the accuracy of the results. The study compares the results obtained from analytical modeling and machine learning algorithms, highlighting the contribution of this research to the optimization of bonded composite repairs in cracked thin-walled structures. The article also references other relevant studies in the field. [Extracted from the article]

This article discusses a study on the fatigue behavior of a natural-based bio-composite material reinforced with fique natural fibers. The study focuses on characterizing the fatigue behavior of fique-reinforced composites to understand their performance and potential applications. The researchers found that the fique-reinforced composites exhibited good fatigue resistance. This research contributes to the development of sustainable materials and opens new market opportunities for rural areas. The document provides a detailed analysis of the mechanical behavior, fatigue resistance, stiffness loss, energy dissipation, and fracture morphology of a composite material called BioPoxy-fique. The material exhibited improved mechanical properties compared to other resins. The study suggests that fique can be a promising reinforcement material for composites. The document also includes a list of references related to natural fiber composites and their mechanical behavior, providing valuable insights for researchers and engineers in the field. [Extracted from the article]

The given document is a list of references cited in an article discussing the Portevin-Le Chatelier effect, a phenomenon observed in certain materials where plastic deformation occurs in a jerky or serrated manner. The references cited include studies on various aspects of the effect, such as its occurrence in different alloys, the role of temperature and strain rate, and the underlying mechanisms. These studies utilize techniques such as experimental observations, modeling, and wavelet analysis to understand and characterize the Portevin-Le Chatelier effect. [Extracted from the article]

This article discusses the strength and ductility of beam-column joints made of Ultra-High-Performance Concrete (UHPC) and Ultra-High-Performance Fiber-Reinforced Concrete (UHPFRC). The study examines the impact of these materials on the behavior of the joints and uses computational simulations to analyze their strength and ductility. The results show that UHPFRC joints have superior strength, enhanced ductility, and a unique damage progression pattern. The article also introduces the concept of energy-based ductility and validates the computational analysis with experimental data. Additionally, the document provides a list of references that cover various aspects of concrete structures, which can be useful for researchers and engineers studying the design and performance of these structures. [Extracted from the article]

This article discusses the analysis of the mechanical behavior of fiber-glass plastic with a hole pattern using digital image correlation and acoustic emission methods. The study focuses on deformation processes, damage accumulation, and fracture in polymer composites in stress concentration zones. The researchers conducted mechanical tensile tests on fiber-glass plastic specimens with different hole patterns and analyzed the displacement and strain fields using a non-contact optical video system. The results showed that the bearing capacity of the material decreased for certain hole patterns, and the fracture patterns varied depending on the hole arrangement. The document also includes references related to the influence of internal technological defects on the mechanical properties of structural CFRP and the AISC specification for structural steel buildings. [Extracted from the article]

The given text is a scientific article or document discussing a mathematical method for analyzing the stress field in a notched strip under tension. The article presents an alternative approach to analytically confront the problem of stress fields in the vicinity of notches, using conformal mapping and complex potentials. The method is validated through comparisons with established solutions and numerical analysis. The results show that the present solution is applicable even for strips with dimensions comparable to the notch. [Extracted from the article]

This paper presents a refined Finite Element (FE) modeling strategy for analyzing the failure behavior of regular masonry structures reinforced with timber-based retrofit solutions. The proposed model schematizes the masonry as brick units, modeled using two-dimensional linear elastic plane stress elements, mutually joined through zero-thickness cohesive interface elements. These interface elements serve to reproduce the nonlinear behavior of masonry because of the occurrence of failure mechanisms of the mortar joints. Reinforced timber frame elements are modeled using truss elements that exhibit elastic brittle fracture behavior. The interaction between the masonry sub-structure and the reinforced timber frame system is accounted for using special constraint conditions that simulate the mechanical behavior of anchorage connections. The reliability of the proposed model in reproducing the failure behavior of masonry is assessed through comparisons with experimental and numerical data available in the literature. Additionally, the efficacy of the retrofit technique based on timber frame structures is investigated in detail through pushover analyses on a two-story masonry wall representative of real-life masonry buildings. The results indicate that the proposed retrofitting strategy is an effective and eco-friendly retrofit solution to enhance the in-plane bearing capacity of masonry structures subjected to horizontal forces.

The paper describes the implementation of 3D numerical simulation in machine learning models used in infrared thermographic nondestructive testing. The enhancement of generalizability of such models emerges as a decisive factor for producing trust-worthy test results. First, it is demonstrated that the models trained on datasets with fixed parameters yield limited defect detection capabilities. The concept of training datasets, which include subtle variations in material thickness, thermal conductivity, as well as various combinations of material density and heat capacity, provides the best learning results and a noticeable ability to identify defects in all test datasets. Second, the model robustness in respect to noise is explored to demonstrate its ability to withstand additive and multiplicative random noise. Third, potentials of some known techniques of thermographic data processing, such as Thermographic Signal Reconstruction, Fast Fourier Transform and Temperature Contrast, are examined. In particular, the use of the Temperature Contrast data ensured sensitivity (True Positive Rate) better than 98% across all test datasets.

The paper is devoted to the development of the method of laser shock peening (LSP) of metals. To optimize the mode of LSP for Ti-6Al-4V specimens a deep learning model for predicting residual stresses by laser shock peening was developed. A numerical-experimental method was used to carry out the model training, in which an experimental study of the effect of different processing mode on the depth and distribution of residual stresses was carried out. The Johnson-Cook model was used as the governing relationship for modeling the dynamic deformation process. At the second stage, the problem of static equilibrium of a body with a plastically deformed area was numerically solved to determine residual stresses. The results of research on determination of the optimal configuration of the deep learning model showed that when using sinusoidal activation function of the neural network with 4 hidden layers and the number of neurons 10, the best level of accuracy in solving the problem is achieved. The obtained model allows us to optimally determine the LSP mode according to the given limitations of values and depth of residual stresses.

This paper presents a novel method of assessing structural damage in beams exposed to moving loads via acceleration signals through experimental studies. In this study, beams are supported on both ends, and their dynamic response to moving loads is assessed. The raw signal has been improved using a random decrement technique. Take measurements from different locations and calculate correlation coefficients between them, then use these as features to evaluate the structure. In order to create a reliable and potential framework for predicting damage efficiently, these features are used as input variables to the machine learning model. The proposed methodology exhibits promising results in accurately discerning and predicting damage in beam structure. It demonstrates a high level of precision to subtle changes in structural integrity when trained by machine learning on the statistical feature extracted from acceleration signals. As a result of this research, methods for detecting structural damage can be made more reliable and efficient by employing machine learning techniques. Additionally, structures operating in dynamic environments can benefit significantly from the proposed methodology.

Material fatigue is extensively discussed and researched within scientific and industrial communities. Fatigue damage poses a significant challenge for both metallic and non-metallic components, often resulting in unexpected failures of in-service parts. Within multiaxial fatigue assessment, critical plane methods have gained importance due to their ability to characterize a component's critical location and detect early crack propagation. However, the conventional approach to calculate critical plane factors is time-consuming, making it primarily suitable for research purposes or when critical regions are already known. In many real-world scenarios, identifying the critical area of a component is difficult due to complex geometries, varying loads, or time limitations. This challenge becomes particularly crucial after topological optimization of components and in the context of lightweight design. Recently, the authors proposed an efficient method for evaluating critical plane factors in closed form, applicable to all cases that necessitate the maximization of specific parameters based on stress and strain components or their combination. This paper presents and validates the proposed methodology, with reference to a rear upright of a FSAE car, which is characterized by a complex geometry and is subjected to non-proportional loading conditions. The efficient algorithm demonstrated a substantial reduction in computation time compared to the standard plane scanning method, while maintaining solution accuracy.

In the present paper, the mechanical behaviour of edge-cracked nanobeams under Mixed-Mode loading is analytically investigated by means of the Stress-Driven nonlocal model. Firstly, the proposed formulation is outlined, and then applied to the case of a cantilever edge-cracked nanobeam. A parametric study is performed by varying both the crack depth and the crack position along the beam axis. Finally, the above formulation is applied to simulate some experimental tests available in the literature.

There are a few kinds of research about box section Reinforced Concrete (RC) beams under the effect of combined shear and torsional stresses. In the present research, the concept of adding external strengthening, in the transverse direction, is adopted. The paper focuses on using Glass Fiber Reinforced Polymer GFRP ropes as near-surface mount stirrups. Nine box-section concrete specimens were decanted and tested. Three variables are adopted, (1) GFRP stirrups diameter, (2) GFRP stirrups inclination, and (3) GFRP stirrups spacing. The experimental results showed considerable enhancement in the shear capacity of the strengthened beams by 8 to 56% depending on the effectiveness of the studied parameters. Ductility and toughness were improved when more intensive strengthening schemes were adopted. The shear capacity of all tested beams based on Egyptian code ECP 208�2019 is calculated and compared with that from American code ACI 440�2019 and Canadian code CSA-A23.3-04. The shear capacity from both Egyptian and American codes compared with experimental loads. The analytical results are conservative in some cases and unconservative in others while the analytical results in general are conservative. The Canadian code CSA-A23.3-04 is unconservative compared to the experimental results for the range of the studied parameters and specimens.

Belgrade fair hall 1 is well known for its dome, which is still the world largest self-supported construction made of pre-stressed concrete, with its diameter of 106 m. In this paper the Finite Element Method (FEM) was performed to analyze different loading and supporting conditions. At the same time, crack growth in a support column was simulated by the extended FEM (XFEM). Results of numerical calculations indicate ingenious design of such a complex structure which was based on �hand� calculation decades ago, without computers. In addition to classical engineering and more advanced numerical calculations, risk based analysis was performed taking into account artificially introduced crack and Failure Analysis Diagram, obtained using stress intensity factor and net stress, as well as fracture toughness and critical stress. This analysis, made for the first time for Belgrade fair hall 1, proved that its structural integrity is jeopardized only when a crack reaches half the thickness of a steel bar

This paper describes a study of recycled concrete under compressive loads. The study was conducted in two main parts. In the first part, experimental tests were carried out on concrete samples with varying levels of substitution (25%, 50%, and 75%) with recycled aggregate in order to measure the mechanical properties of the recycled concrete. In the second part of the study, a nonlinear homogenization model was developed on the basis of a classical secant approach to predict the behavior of recycled concrete. In this model, we assume that the behavior of the mortar phase, the concrete, and the recycled aggregates follow Mazars damage law. Comparison with the experimental data shows that the proposed homogenization model is accurate and efficient in predicting the correct nonlinear behavior of the recycled concrete. By better understanding the properties and behavior of recycled concrete, it will be possible to develop more effective methods for incorporating recycled materials into concrete structures

In several industrial applications, plastic, composites and ceramics replace a number of metallic structures such as copper, aluminum and steel. Most recently installed piping water and gas systems in the world are made of thermoplastic due to its advantages, for example, low cost, ease of fabrication and corrosion resistance. In this work, the chosen material is chlorinated polyvinyl chloride (CPVC); the best one used to transport cold and hot water beside simplicity of installation. Notwithstanding, the pipes in service are submitted to different loads, related to environmental, thermal and mechanical effects which procure to mechanisms of degradation. The aim of this article is to assess the effect of the defect on CPVC pipes, through a study of the defect criticality in the form of semi-elliptical, then the ability to predict defected pipes residual life. Therefore unexpected and sudden failure caused by pipes accelerated damage. Therefore, we performed burst tests on both pre-damaged CPVC pipes and virgin ones. To lead our work in this paper, interested in the damage modeling and the failure analysis of CPVC pipes, we adapted the model of unified theory static damage, originally developed in fatigue. We used burst pressure tests to identify the limits of three damage progression phases and, in turn, to calculate the critical life fraction at which these flaws become harmful. Furthermore, we identify the critical depth for the studied defect. These results and techniques enable industrialist s to anticipate this structures service life under these conditions after that set up a robust system of maintenance to ensure a reliable and safe functioning of the structure.

The paper describes the results of an experimental study of a polyurethane material treated by ion implantation technology. The problems of crack growth in the near-surface layer carbonized by ion treatment were investigated using digital optical microscopy. The methods of atomic force microscopy allowed studying the possibility of carbonized layers delamination from the substrate. As a result, the technology for the production of a multilayer polyurethane material with nanofillers (nanotubes, nanodiamonds, fullerenes, graphenes) and its optimal modification by ion implantation treatment was developed, which makes it possible to improve the biocompatibility of polyurethane implants with human tissues