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This study aims to enhance the understanding of fiber-reinforced polymer (FRP) applications in partially confined concrete, with a specific focus on improving economic value and load-bearing capacity. The research addresses the need for a more comprehensive analysis of non-uniform vertical strain responses and precise stress–strain models for FRP partially confined concrete.

DIC and strain gauges were employed to gather data during axial compression tests on FRP partially confined concrete specimens. Finite element analysis using ABAQUS was utilized to model partial confinement concrete with various constraint area ratios, ranging from 0 to 1. Experimental findings and simulation results were compared to refine and validate the stress–strain model.

The experimental results revealed that specimens exhibited strain responses characterized by either hardening or softening in both vertical and horizontal directions. The finite element analysis accurately reflected the relationship between surface constraint forces and axial strains in the x, y and z axes under different constraint area ratios. A proposed stress–strain model demonstrated high predictive accuracy for FRP partially confined concrete columns.

The stress–strain curves of partially confined concrete, based on Teng's foundation model for fully confined stress–strain behavior, exhibit a high level of predictive accuracy. These findings enhance the understanding of the mechanical behavior of partially confined concrete specimens, which is crucial for designing and assessing FRP confined concrete structures.

This research introduces innovative insights into the superior convenience and efficiency of partial wrapping strategies in the rehabilitation of beam-column joints, surpassing traditional full confinement methods. The study contributes methodological innovation by refining stress–strain models specifically for partially confined concrete, addressing the limitations of existing models. The combination of experimental and simulated assessments using DIC and FEM technologies provides robust empirical evidence, advancing the understanding and optimization of FRP-concrete structure performance. This work holds significance for the broader field of concrete structure reinforcement.

The present paper aims to explore a computational homogenisation procedure to investigate the full geometric representation of yield surfaces for isotropic porous ductile media. The effects of cell morphology and imposed boundary conditions are assessed. The sensitivity of the yield surfaces to the Lode angle is also investigated in detail.

The microscale of the material is modelled by the concept of Representative Volume Element (RVE) or unit cell, which is numerically simulated through three-dimensional finite element analyses. Numerous loading conditions are considered to create complete yield surfaces encompassing high, intermediate and low triaxialities. The influence of cell morphology on the yield surfaces is assessed considering a spherical cell with spherical void and a cubic RVE with spherical void, both under uniform strain boundary condition. The use of spherical cell is interesting as preferential directions in the effective behaviour are avoided. The periodic boundary condition, which favours strain localization, is imposed on the cubic RVE to compare the results. Small strains are assumed and the cell matrix is considered as a perfect elasto-plastic material following the von Mises yield criterion.

Different morphologies for the cell imply in different yield conditions for the same load situations. The yield surfaces in correspondence to periodic boundary condition show significant differences compared to those obtained by imposing uniform strain boundary condition. The stress Lode angle has a strong influence on the geometry of the yield surfaces considering low and intermediate triaxialities.

The exhaustive computational study of the effects of cell morphologies and imposed boundary conditions fills a gap in the full representation of the flow surfaces. The homogenisation-based strategy allows us to further investigate the influence of the Lode angle on the yield surfaces.

The purpose of this paper is to provide a comprehensive review of a non-contact full-field optical measurement technique known as digital image correlation (DIC).

The approach of this review paper is to introduce the research pertaining to DIC. It comprehensively covers crucial facets including its principles, historical development, core challenges, current research status and practical applications. Additionally, it delves into unresolved issues and outlines future research objectives.

The findings of this review encompass essential aspects of DIC, including core issues like the subpixel registration algorithm, camera calibration, measurement of surface deformation in 3D complex structures and applications in ultra-high-temperature settings. Additionally, the review presents the prevailing strategies for addressing these challenges, the most recent advancements in DIC applications across quasi-static, dynamic, ultra-high-temperature, large-scale and micro-scale engineering domains, along with key directions for future research endeavors.

This review holds a substantial value as it furnishes a comprehensive and in-depth introduction to DIC, while also spotlighting its prospective applications.

This paper aims to present two Anand’s model parameter sets for the multilayer silver–tin (AgSn) transient liquid phase (TLP) foils.

The AgSn TLP test samples are manufactured using pre-defined optimized TLP bonding process parameters. Consequently, tensile and creep tests are conducted at various loading temperatures to generate stress–strain and creep data to accurately determine the elastic properties and two sets of Anand model creep coefficients. The resultant tensile- and creep-based constitutive models are subsequently used in extensive finite element simulations to precisely survey the mechanical response of the AgSn TLP bonds in power electronics due to different thermal loads.

The response of both models is thoroughly addressed in terms of stress–strain relationships, inelastic strain energy densities and equivalent plastic strains. The simulation results revealed that the testing conditions and parameters can significantly influence the values of the fitted Anand coefficients and consequently affect the resultant FEA-computed mechanical response of the TLP bonds. Therefore, this paper suggests that extreme care has to be taken when planning experiments for the estimation of creep parameters of the AgSn TLP joints.

In literature, there is no constitutive modeling data on the AgSn TLP bonds.

This paper aims to estimate the bearing capacity of a surface strip and circular footings lying on layered sand using numerical limit analysis.

Lower and upper bound limit analysis, as well as finite elements and second-order conic programming (SOCP), are used in this analysis. The yield criterion of Mohr-Coulomb is used to model soil behavior. Using this technique, stringent lower and upper bounds on ultimate bearing capacity can be achieved by assuming an associated flow law.

The obtained results indicate that the exact collapse load is typically being bracketed to within 6% about a mean of both the bounds. The obtained results are compared with the existing literature wherever applicable.

To the best of the authors’ knowledge, no study has used lower and upper bound limit analysis, as well as finite elements and SOCP, to estimate the bearing capacity of a surface strip and circular footings lying on layered sand.

In this study, the effects of strain rate on the bending strength of full-scale wide-flange steel beams have been examined at elevated temperatures. Both full-scale loaded heating tests under steady-state conditions and in-plane numerical analysis using a beam element have been employed.

The load–deformation relationships in 385 N/mm²-class steel beam specimens was examined using steady-state tests at two loading rate values (0.05 and 1.00 kN/s) and at two constant member temperatures (600 and 700 °C). Furthermore, the stress–strain relationships considering the strain rate effects were proposed based on tensile coupon test results under various strain rate values. The in-plane elastoplastic numerical analysis was conducted considering the strain rate effect.

The experimental test results of the full-scale steel beam specimens confirmed that the bending strength increased with increase in strain rate. In addition, the analytical results agreed relatively well with the test results, and both strain and strain rate behaviours of a heated steel member, which were difficult to evaluate from the test results, could be quantified numerically.

The novelty of this study is the quantification of the strain rate effect on the bending strength of steel beams at elevated temperatures. The results clarify that the load–deformation relationship of steel beams could be evaluated by using in-plane analysis using the tensile coupon test results. The numerical simulation method can increase the accuracy of evaluation of the actual behaviour of steel members in case of fire.

While the phenomenon of technostress has received significant attention from researchers in recent years, empirical findings concerning the consequences of specific forms of techno-stressors have remained scattered and contradictory. The authors aim to integrate the conclusions of previous studies to understand the effects of specific techno-stressors on strain and job performance.

This study employs meta-analytic techniques to calibrate the findings of 67 studies investigating more than 63,100 employees.

In general, not all techno-stressors have adverse effects. In particular, techno-uncertainty does not impact job performance. In addition, relative weight analyses reveal the relative importance of techno-complexity and techno-insecurity as predictors of both strain and job performance. Finally, this study finds that the effects of specific techno-stressors on job performance vary depending on research participants' gender, educational attainment and employment status.

First, this study provides a more nuanced view of the effects of specific techno-stressors. Second, this research clarifies the relative importance of specific techno-stressors as predictors of strain and job performance. Finally, this study reveals the moderating effects of demographic variables on the relationships between specific techno-stressors and job performance.

In structural health monitoring, localization of multiple slight damage without baseline data is significant and difficult. The purpose of this paper is to discuss these issues.

Damage in the structure causes singularities of displacement modes, which in turn reveals damage. Methods based on the displacement modes may fail to accurately locate the slight damage because the slight damage in engineering structure results in a relatively small variation of the displacement modes. In comparison with the displacement modes, the strain modes are more sensitive to the slight damage because the strain is the derivative of the displacement. As a result, the slight variation in displacement data will be magnified by the derivative, leading to a significant variation of the strain modes. A novel method based on strain modes is proposed for the purpose of accurately locating the multiple slight damage.

In the two bay beam and steel fixed-fixed beams, the numerical simulations and the experimental cases, respectively, illustrate that the proposed method can achieve more accurate localization in comparison with the one based on the displacement modes.

The paper offers a practical approach for more accurate localization of multiple slight damage without baseline data. And the robustness to measurement noise of the proposed method is evaluated for increasing levels of artificially added white Gaussian noise until its limit is reached, defining its range of practical applicability.

This paper aims to investigate the responses of single piles and pile groups due to tunneling-induced ground movements in a two-layered soil system. The analyses mainly focus on the additional single pile responses in terms of bending moment, lateral deflection, axial force, shaft resistance and pile settlement. Subsequently, a series of parametric studies were carried out to better understand the responses of single piles induced by tunneling. To give further understanding regarding the pile groups, a 2 × 2 pile group with two different pile head conditions, namely, free and capped, was considered.

Using the PLAXIS three-dimensional (3D) software, a full 3D numerical modeling is performed to investigate the effects of ground movements caused by tunneling on adjacent pile foundations. The numerical model was validated using centrifuge test data found in the literature. The relevance of the 3D model is also judged by comparison with the 2D plane strain model using the PLAXIS 2D code.

The numerical test results reveal that tunneling induces significant displacements and internal forces in nearby piles. The magnitude and distribution of internal forces depend mainly on the position of the pile toe relative to the tunnel depth and the distance between the pile and the vertical axis of the tunnel. As the volume loss increases from 1% to 3%, the apparent loss of pile capacity increases from 11% to 20%. By increasing the pile length from 0.5 to 1.5 times, the tunnel depth, the maximum pile settlement and lateral deflection decrease by about 63% and 18%, respectively. On the other hand, the maximum bending moment and axial load increase by about 7 and 13 times, respectively. When the pile is located at a distance of 2.5 times the tunnel diameter (Dt), the additional pile responses become insignificant. It was found that an increase in tunnel depth from 1.5Dt to 2.5Dt (with a pile length of 3Dt) increases the maximum lateral deflection by about 420%. Regarding the interaction between tunneling and group of piles, a positive group effect was observed with a significant reduction of the internal forces in rear piles. The maximum bending moment of the front piles was found to be higher than that of the rear piles by about 47%.

Soil is a complex material that shows differently in primary loading, unloading and reloading with stress-dependent stiffness. This general behavior was not possibly being accounted for in simple elastic perfectly plastic Mohr–Coulomb model which is often used to predict the behavior of soils. Thus, in the present study, the more advanced hardening soil model with small-strain stiffness (HSsmall) is used to model the non-linear stress–strain soil behavior. Moreover, unlike previous studies THAT are usually based on the assumption that the soil is homogeneous and using numerical methods by decoupled loadings under plane strain conditions; in this study, the pile responses have been exhaustively investigated in a two-layered soil system using a fully coupled 3D numerical analysis that takes into account the real interactions between tunneling and pile foundations. The paper presents a distinctive set of findings and insights that provide valuable guidance for the design and construction of shield tunnels passing through pile foundations.

This study aims to examine social determinants and social strains of cyberbullying victimization among expatriate populations in high-income countries such as Qatar. The authors argue that expatriate students will be exposed to stains and pressures due to several factors, such as feeling alienated, lonely, homesick, insecure and helpless. This study examines a partial assumption of general strain theory (GST), which posits that expats’ cyberbullying victimization can create negative stimuli that lead to negative feelings and, as a result, to delinquent behavior. The delinquent behavior can be seen as a coping method in encountering strains. Logistic regression analysis is applied (using SPSS v. 21) to test the hypothesis that the victimization of expats’ cyberbullying could lead to strain and delinquency.

A sample of 2,428 expatriate students (46% males and 54% females) was randomly selected from seven public schools in Qatar. The average number of siblings in the household was 2.7. Around 10.8% of the sample reported victimization by cyberbullying. Most came from intact families (80.6%) compared to 19.4 living in broken homes. Concerning the birth order of the student in the family, 25% of the sample were firstborn, and 20% were middle-born. Students’ mother relationships were higher than students’ father relationships (69% vs 51%, respectively). Fathers were higher in undergraduate education than mothers (60% vs 49%, respectively). Considering that 58% of women did not have a job, most fathers work in administrative positions (47% in administrative work and 39% in professional positions) as opposed to mothers’ positions (15% and 21%, respectively). The survey was distributed among expatriate students by trained researchers, teachers and social workers in public schools. The researchers explained the purpose of the study, confidentiality and potential risks and provided directions for completing the survey. Parents and their children provided signed informed consent before participation, following the institutional review boards of Qatar University’s Human Subject Research Committee and the Ministry of Social Development. The victimization of cyberbullying is measured at the dichotomy level by asking a general cyberbullying question (In the last 12 months, had you been bullied by other students using mobile messages, email, voice or video messages? Responses were 1 – yes and 0 – no). A definition of cyberbullying was included in the questionnaire. Independent measures are as follows: (1) demographic variables: gender, belief, health, number of friends and exposure to violence; (2) family variables: delinquent family, coercive parenting, family relations, family disputes, father absence and family ties; (3) school variables: school satisfaction, school violence, student fighting, teachers' violence, school truancy and going late to school; (4) imprudent behavior: smoking, alcohol, not using a seat belt, gambling, stealing less than 100 QR, chewing tobacco, stimuli, volatile drugs, sexual harassment, throwing garbage out of the car, cheating, vandalism and victimization.

Findings showed that n = 255, 10.8% of the expats’ sample N = 2,428 reported victimization of cyberbullying, of whom 46% were males and 54% were females. A total of 24% of the victims of cyberbullying were males, and 5.8% were females. About a third of the sample were cyberbullying perpetrators (n = 716, 29.5%). Victims of cyberbullying came from intact families (62.4%) compared to broken families (37.6%). A round third of the victims reported the absence of a father during their childhood (n = 78, 31.7%). Most of the victims came from a typical community compared to the delinquent community (71.2% vs 28.2%). About a third of the victims reported it was easy to talk with the father when needed (32% compared to 42.7%), who said it was easy. More than half of the victims do not use seat belts. A low percentage of them were gambling (n = 68, 27% or 2.9% of the total sample). Regarding escaping imprudent and delinquent behaviors, findings showed that a third and more than a tenth of the cyberbullying were smokers and alcoholics (n = 69, 27.4% and n = 42, 16.7% respectively). Moreover, among the most serious, widely spread student problems, around a quarter of the victims reported using chewing tobacco (Sweeka is the local name) (n = 54, 21.4%). Finally, drug use among victims was more than a tenth of them (n = 41, 16.3%). About a quarter of the victims reported stealing less than 100 QR (n = 67, 26.8% or 2.9% of the total sample). Concerning the crimes committed by victims, findings showed that more than forth of them committed assault (n = 71, 28.3%), student fights (n = 202, 80.8%), school violence (n = 117, 46.6%) and half of the victims (50.2%) were also victims of face-to-face bullying. Little below half of the sample was exposed to violence (n = 120, 48.6%) and was the victim of violence in the past 12 months (n = 100, 40.8%). A significant gender differences was found in the victimization of cyberbullying (1 = yes, 0 = no) (a = 000). Moreover, significant mean differences were found between expatriates student victimization of cyberbullying at (a = 000) in all strain variables. Using binary regression analysis to examine the equality of probability of being a victim of cyberbullying as accounted for by the independent variables, the model’s predictability was 89.4%. The Hosmer and Lemeshow test and omnibus tests support the model’s fit (a = 000). Nagelkerke R² shows that the stain variables accounted for 24% of the variance in the expat's student victimization of cyberbullying.

Conceptualization and determination of what constitutes cyberbullying from the criminal law perspective are needed. Cyberbullying is defined as a form of violence and crime involving new technologies (Sun et al., 2016, p. 62). Policymakers should provide accessible and equitable access to the criminal justice system, the integration of expatriates and the provision of support services to avoid delinquency.

A social cohesion, inclusion and well-being policy is needed for expatriate students and their families in Qatar. In particular, cultural diversity policy and programs, a source of strength and enrichment should be promoted in educational settings. Social inclusion and cultural diversity programs could ease the alienation and marginalization that expatriate students may encounter in their host societies to prevent stains and negative emotions that lead to delinquency and criminal behaviors. Access to support services without discrimination to avoid health and psychological strains and risk factors. This includes but is not limited to avoidance of stigmatization, embarrassment, sense of helplessness, humiliation and other negative feelings toward expatriates. Awareness and promotion of cultural diversity values are needed to enhance cultural acceptance to reduce victimization among the expatriate population. Criminal law and security implications conceptualization and determination of what constitutes cyberbullying from the criminal law perspective are needed. Cyberbullying is a form of violence and crime involving new technologies (Sun et al., 2016). Policymakers should provide accessible and equitable access to the criminal justice system, integrating expatriates and providing support services to avoid delinquency. There is a pressing need for further research within the realm of crime and law to establish the precise legal boundaries surrounding cyberbullying and to delineate the potential scope for legislative measures aimed at safeguarding against victimization in Qatar. Although the state of Qatar has taken steps to address cyberbullying by incorporating it into relevant legal frameworks, there remains a gap in terms of specifically targeting cyberbullying involving children and adolescents. Despite the introduction of the new Cybercrime Prevention Law, the issue of cyberbullying among these vulnerable groups is not adequately addressed.

Social implication includes but is not limited to avoidance of stigmatization, embarrassment, sense of helplessness, humiliation and other negative feelings towards expatriate. Awareness and promotion of cultural diversity values is needed to enhance cultural acceptance to reduce victimization among expatriate population.

The present study examines some strain theory assumptions and the victimization of the cyberbullying expatriate population. This study tests a partial assumption of GST, which states that the expatriate population’s exposure to the victimization of cyberbullying can lead to negative stimuli that, in return, create negative feelings and, as a result, imprudent and delinquent behavior. The cyberbullying behavior can be seen as an escaping and coping method in encountering strains. This study underscores the presence of cyberbullying within high schools among expatriate students, exerting significant effects on their personal, social and emotional behaviors. The novel insights gleaned from this investigation contribute substantively to the comprehension of both the pervasiveness and repercussions of cyberbullying on the well-being of expatriate students. This contribution is particularly vital, given the dearth of research in the field, largely attributable to the growing dependence of students on the internet for various cyber activities. This study examines a partial assumption of GST (in non-Western country). Moreover, it uses an advanced statistical analysis and large sample.