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Even though it is widely used, reinforced concrete (RC) is susceptible to damage from various environmental factors. The hazard of a fire attack is particularly severe because it may cause the whole structure to collapse. Furthermore, repairing and strengthening existing structures with high-performance concrete (HPC) has become essential from both technical and financial points of view. In particular, studying the postfire behavior of HPC with normal strength concrete substrate requires experimental and numerical investigations. Accordingly, this study aims to numerically investigate the post-fire behavior of reinforced composite RC slabs.

Consequently, in this study, a numerical analysis was carried out to ascertain the flexural behavior of simply supported RC slabs strengthened with HPC and exposed to a particularly high temperature of 600°C for 2 h. This behavior was investigated and analyzed in the presence of a number of parameters, such as HPC types (fiber-reinforced, 0.5% steel, polypropylene fibers [PPF], hybrid fibers), strengthening side (tension or compression), strengthening layer thickness, slab thickness, boundary conditions, reinforcement ratio and yield strength of reinforcement.

The results showed that traction-separation and full-bond models can achieve accuracy compared with experimental results. Also, the fiber type significantly affects the postfire performance of RC slab strengthened with HPC, where the inclusion of hybrid fiber recorded the highest ultimate load. While adding PPF to HPC showed a rapid decrease in the load-deflection curve after reaching the ultimate load.

The proposed model accurately predicted the thermomechanical behavior of RC slabs strengthened with HPC after being exposed to the fire regarding load-deflection response, crack pattern and failure mode. Moreover, the considered independent parametric variables significantly affect the composite slabs’ behavior.

The use of recycled coarse aggregate in concrete structures promotes environmental sustainability; however, performance of these structures might be negatively impacted when it is used as a replacement to traditional aggregate. This paper aims to simulate recycled concrete beams strengthened with carbon fiber-reinforced polymer (CFRP), to advance the modeling and use of recycled concrete structures.

To investigate the performance of beams with recycled coarse aggregate concrete (RCAC), finite element models (FEMs) were developed to simulate 12 preloaded RCAC beams, strengthened with two CFRP strengthening schemes. Details of the modeling are provided including the material models, boundary conditions, applied loads, analysis solver, mesh analysis and computational efficiency.

Using FEM, a parametric study was carried out to assess the influence of CFRP thickness on the strengthening efficiency. The FEM provided results in good agreement with those from the experiments with differences and standard deviation not exceeding 11.1% and 3.1%, respectively. It was found that increasing the CFRP laminate thickness improved the load-carrying capacity of the strengthened beams.

The developed models simulate the preloading and loading up to failure with/without CFRP strengthening for the investigated beams. Moreover, the models were validated against the experimental results of 12 beams in terms of crack pattern as well as load, deflection and strain.

The paper aims to introduces an experimental work to investigate the torsional behavior of reinforced concrete (RC) beams strengthened by near-surface mounted (NSM) carbon fiber-reinforced polymer (CFRP) ropes.

In this research, nine rectangular RC beams of 250 mm × 300 mm cross-section and 1,600 mm in length were constructed and tested considering the studied parameters. These parameters include the length of the CFRP rope, the orientation of the CFRP rope, the arrangement of longitudinal and the scheme of NSM-CFRP ropes.

In comparison to control specimens, the results demonstrate a considerable improvement in the torsional response of RC beams strengthened with the CFRP rope. Additionally, specimens strengthened with 90° vertical ropes increase torsional moment capacity more efficiently than specimens strengthened with 45° inclined ropes since the stress concentration leads to premature debonding of the CFRP rope. Whereas RC beams' ability to withstand torsional moments is reduced as the distance between reinforcing CFRP ropes is increased. According to test results, adding CFRP ropes to RC beams' bottoms had a slightly positive impact on torsional response.

This paper fulfills an identified need to study how the using of the CFRP rope is effective in strengthening RC beam subjected to torsion moment.

Recently, the repairing of reinforced concrete (RC) structures attracted great research attentions, but the research interests were mainly concentrated on common repairing types. To this end, in this paper, a repairing of pre-loaded RC beams strengthened by aramid reinforcement polymers (AFRP) is presented. Furthermore, the purpose of this paper is to study the behavior of pre-loaded RC Deep beams under sustained load. The AFRP has many advantages such as controlling stresses distribution around the openings, controlling failure modes, and enhancing the structural capacity of pre-cracked RC beams.

Four specimens were experimentally tested: one specimen without strengthening, which is considered as control specimen, one strengthened specimen using AFRP without pre-cracking and two specimens subjected to pre-cracking load before prior to AFRP application. Furthermore, after validation of experimental data by using ANSYS software, a parametric study was conducted to investigate the effect of pre-damage level on shear capacity of RC beams. For pre-cracked beams, loading was first applied until the cracking stage, followed by specimen repairing with epoxy injection, and then the specimens were loaded again until failure point.

The result showed that pre-damage level and AFRP strengthening have great influence on the ultimate strength and failure mode. In addition, the results obtained from experimental tests were compared with those from numerical validation with ANSYS and showed good agreement.

Based on ACI guidelines, an analytical equation for calculating the shear strength of strengthened RC beams with openings subjected to pre-damage was then proposed, and the calculated results were compared with those from the tests, with differences not exceeding 10%.

The main aim of this study is to examine the behavior of reinforced concrete short columns strengthened using longitudinal near surface mounted (NSM)-carbon fiber reinforced polymer (CFRP) strips.

A full 3D-finite element (FE) model was developed using ABAQUS in order to conduct the analysis. The model is first validated based on experimental data available in the literature, and then the effect of concrete compressive strength, number of CFRP strips that are used and the spacing between them were taken in consideration for both concentric and eccentric loading cases. The parametric study specimens were divided into three groups. The first group consisted of unstrengthened columns and served as control specimens. The second group consisted of columns strengthened by longitudinal CFRP strips at two opposite column faces.

The results of this study are used to develop interaction diagrams for CFRP-strengthened short columns and to develop best-fit equations to estimate the nominal axial load and moment capacities for these strengthened columns. The results showed that the specimens that were strengthened using more longitudinal CFRP strips showed a significant increase in axial load capacity and a significant improvement in the interaction diagram, especially at large load eccentricity values. This result can be justified by the fact that longitudinal strips effectively resist the bending moment that is generated due to eccentric loading. Generally, the process of strengthening using longitudinal strips only has a reasonable effect and it can be typically considered an excellent choice considering the economic aspect when the budget of strengthening is limited.

This research aims at studying the performance of strengthened rectangular reinforced concrete short columns with CFRP strips using FE method, developing interaction diagrams of strengthened columns in order to investigate the effect of different parameters such as compressive strength (20, 30 and 40 MPa), number of CFRP strips (1, 2, 3 and 4) and the spacing between CFRP strips in terms of the ratio of CFRP center point distance to column outside dimension ratio (0.60, 0.70 and 0.80) on the behavior of strengthened RC columns and improving empirical formulas to predict the nominal axial load and moment capacities of strengthened RC columns. These parameters that directly affect short column load carrying capacity are presented in ACI-318 (2014).

This study aims to provide the main contents of the revision of the 2023 OECD Guidelines for Multinational Enterprises and suggest implications for the Korean government and multinational enterprises.

Following the brief history of the revision of OECD Guidelines for Multinational Enterprises, this study reviews and evaluates major substantive and procedural revisions of the 2023 OECD Guidelines, and then suggests countermeasures for Korean government and businesses.

The most significant substantive change of the 2023 revision is that expectations for environmental due diligence and disclosure obligations, including climate change and biodiversity, for multinational enterprises have been expanded and strengthened. Regarding procedural changes, the biggest change is the introduction of a basis rule for the National Contact Points for Responsible Business Conduct (NCPs for RBC) to judge each issue and a rule that the final statement must include follow-up details and deadlines, which is expected to strengthen the effectiveness of the NCP dispute resolution mechanism.

This study is the first academic paper to introduce major substantive and procedural revisions to the 2023 OECD Guidelines for Multinational Enterprises in Korea. This study also provides implications for the Korean government and companies following the 2023 revised OECD Guidelines for Multinational Enterprises as follows. First, the Korean government must establish a public–private partnership to closely communicate to prevent Korean companies from being harmed by failing to meet strengthening international Environment, Social and Governance (ESG) standards. In addition, Korean government should actively participate in ESG-related international forums, including the OECD, and strive to reflect the needs and interests of Korean companies. Second, the Korean NCP should strengthen its activities to prevent potential damage by expanding education and promotions for Korean businesses on related overseas legislative trends and NCP dispute case studies so that Korean companies can effectively deal with the strengthened ESG standards. Third, Korean multinational enterprises should preemptively establish an advanced ESG management system to seize new opportunities in the global supply chain previously concentrated in China and India in the process of reorganizing global supply chains according to the trend of strengthening ESG standards and the US value alliance strategy.

This study uses relationship marketing theory to explore affective and calculative commitment as mediators in the delight–loyalty link. Furthermore, it investigates the role of perceived employee service delivery skills, perceived value and trust in the relationships between delight, affective commitment, calculative commitment and loyalty.

A descriptive research approach was applied, and the data were collected from 332 retail banking customers in an emergent market who are overall satisfied with their bank. A self-administered questionnaire collected data from 332 respondents who adhered to the stipulated requirements to participate in the study. These respondents were selected through purposive and convenience sampling. The constructs’ interrelationships were analysed via structural equation modelling. The measurement and structural models were also assessed.

Affective and calculative commitment and delight impact loyalty. Both affective commitment and calculative commitment were found to mediate the relationship between delight and customer loyalty.

The study enhances an understanding of the role of affective and calculative commitment in strengthening the delight–loyalty link from a relationship marketing theory perspective.

The study provides guidance to the retail banking industry in emerging markets on the importance of affective and calculative commitment in strengthening the delight–loyalty link. It further informs retail banks of the need to provide banking customers with products and service value that exceed their expectations to strengthen their future commitment and loyalty to their bank.

Guided by relationship marketing theory, the role of affective and calculative commitment in mediating the delight–loyalty link in an emerging market context is uncovered.

The purpose of this paper is to understand the functioning of a mutual aid group for mental health in rural area and analyze their own strategies for the recovery of mental health, especially those focused on cooperation, social innovation and the strengthening of their own culture through coffee.

The qualitative approach was addressed through the thematic analysis, method to identify, analyze and report patterns within the data. For the selection of participants, the members of a mutual aid group called “Cooperativa de Mujeres' was selected. This group functions as an autonomous business organization in Risaralda, Colombia. They have accompanied people diagnosed with anxiety, depression and domestic violence. Six women were interviewed, between the ages of 18 and 62.

Two thematic nuclei are described: “One for all” made up of categories such as identification with the other, need for the other, being able to communicate, contributing to the group involuntarily and actions to help others. “All for one”, made up of categories such as growing together, welcoming individuals in their individuality from group dynamics, strengthening the relationship of the person with reality, strengthen from the experiences of others.

Mutual Aid Groups in mental health propose associative structures that they seek to oppose the barriers of historical exclusion in the labor field and in this way contribute to the fact that the models, although they have a long history, have been little studied with a view to their implementation by health systems.

Current research in the field of health should focus on recognizing the flaws of the current mental health model focused on medicalization, psychologization and institutionalization, and point to a greater commitment to intersectoral support for initiatives and scenarios that promote links, networks, autonomy and care for each other and the environment, where sustainability and social and economic growth are fundamental.

The transformative actions of cooperatives are configured with a fundamental element when it comes to generating spaces for the rehabilitation of mental health.

Components of a mutual aid group in rural areas are explored, which could serve to replicate said structures in similar scenarios, especially in territories where social inequities make recovery difficult, such as Colombia.

The study’s aim was to design and test a leadership development approach using blended learning, to equip leaders for strengthening their own resilience and that of their teams.

A contextualised leadership development intervention was produced and evaluated following the principles of design-based research. Participants were from three organisations that work internationally to address the impact of economic disadvantage. Initial research used the behavioural event interview technique. Online assessment incorporated measures of situational judgement, emotion recognition and attributional style. Validity measures were multi-rater feedback (criterion), and NEO-PI 3 (construct). Individual feedback and a simulation-based peer workshop were followed by a four-to-six month period of experience-driven development and a final peer workshop for consolidating and evaluating learning outcomes.

The online assessment was a valid measure of leaders’ personal resilience resources and their resilience-building capability. Overall, the intervention improved participants’ understanding of, and engagement with, the processes of strengthening individual and collective (team) resilience.

The target sample size for the study was relatively small, to ensure it would be practical to replicate the approach when designing similar interventions for a senior leadership population in other contexts. Significant results provided robust evidence for the validity of the assessment approach. Findings for the workshops and experience-driven development phase were more tentative, but the value of the design iterations was clearly demonstrated.

The leadership development approach is suitable for application in other organisations, if similar principles are followed to produce and evaluate materials relevant to each broad sector context. Roll-out is cost-effective, with relatively few hours of blended or virtual delivery supporting experience-driven learning.

The impact leaders have on the wellbeing of those who report to them is well established, but less has been done to develop and formally evaluate practical, cost-effective interventions to improve this impact. The approach validated in this study can be applied more widely to benefit employee wellbeing as well as performance.

The study developed and evaluated a new approach to preparing leaders for the challenge of building team resilience, an aspect of leadership capability that has been given relatively little attention to date.

The purpose of this study is to detect the effect of some natural cellulosic polymers in their nano forms with the addition of zinc oxide nanoparticles on restoring the lost mechanical strength of degraded papyrus without any harmful effects on the inks.

In the current study, the USB digital microscopy, scanning electron microscope, measurement of mechanical properties (tensile and elongation), pH measurement, color change and infrared spectroscopy were undertaken for the samples before and after treatment and aging.

In the current study, the USB digital microscopy, scanning electron microscope, measurement of mechanical properties (tensile and elongation), pH measurement, color change and infrared spectroscopy were undertaken for the samples before and after treatment and aging.

The effect of strengthening materials was studied on cellulose and carbon ink, which makes this study closer to reality as the manuscript is the consistent structure of cellulose and inks, whereas most of the literature stated the impact of consolidation materials on the strengthening the cellulosic supports without attention to their impact on inks.