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This study aims to determine the effect of replacing a portion of the cement in the concrete mixture with silica fume (SF) on the corrosion resistance of reinforcing bars, the compressive strength of concrete and the tensile strength of hook bars in both corroded and non-corroded external joints of structures. The external beam-column connection was studied because of its critical role in maintaining structural continuity in all three directions and providing resistance to rotation.

In external concrete joints, the bars at the end of the beams are often bent at 90° to form hooks that embed in columns. Owing to the importance of embedding distance and the need to understand its susceptibility to corrosion damage from chloride attack, a series of experiments were conducted on 12 specimens that accurately simulate real-site conditions in terms of dimensions, reinforcement and hook bars. SF was replaced with 10% and 15% of the weight of cement in the concrete mixture. To simulate corrosion, the specimens were subjected to accelerated corrosion in the laboratory by applying a low continuous current of 0.35 mA for 58 days.

The results revealed the effect of SF in improving the compressive strength of concrete, the pullout resistance of the hook bars and the corrosion resistance. In addition, it showed an apparent effect of the corrosion of reinforcing bars in reducing the bonding strength of hook bars with concrete and the effect of SF in improving this strength.

It was noted that the improvement of the results, achieved by replacing 10% of the weight of cement with SF, was significantly close to the results obtained by replacing 15% of the SF. It is recommended that an SF ratio of 10% be adopted to achieve the greatest economic savings.

Unconventional machining processes, particularly ultrasonic vibration cutting (UVC), can overcome such technical bottlenecks. However, the precise mechanism through which UVC affects the in-service functional performance of advanced aerospace materials remains obscure. This limits their industrial application and requires a deeper understanding.

The surface integrity and in-service functional performance of advanced aerospace materials are important guarantees for safety and stability in the aerospace industry. For advanced aerospace materials, which are difficult-to-machine, conventional machining processes cannot meet the requirements of high in-service functional performance owing to rapid tool wear, low processing efficiency and high cutting forces and temperatures in the cutting area during machining.

To address this literature gap, this study is focused on the quantitative evaluation of the in-service functional performance (fatigue performance, wear resistance and corrosion resistance) of advanced aerospace materials. First, the characteristics and usage background of advanced aerospace materials are elaborated in detail. Second, the improved effect of UVC on in-service functional performance is summarized. We have also explored the unique advantages of UVC during the processing of advanced aerospace materials. Finally, in response to some of the limitations of UVC, future development directions are proposed, including improvements in ultrasound systems, upgrades in ultrasound processing objects and theoretical breakthroughs in in-service functional performance.

This study provides insights into the optimization of machining processes to improve the in-service functional performance of advanced aviation materials, particularly the use of UVC and its unique process advantages.

This paper aims to examine dissimilar joints for various applications in chemical, petrochemical, oil, gas, shipbuilding, defense, rail and nuclear industry.

This study examined the effects of cold metal transfer welding on stainless steel welds for 316L austenitic and 430 ferritic dissimilar welds with ER316L, ER309L and without (autogenous) fillers. The microstructural observation was done with an optical microscope. The mechanical test was done to reveal the strength, hardness and toughness of the joint. The electrochemical polarization tests were done to reveal intergranular and pitting corrosion in the dissimilar joints.

This microstructural study shows the presence of austenitic and ferritic phases with vermicular ferrite for ER309L filler weld, and for ER316L filler weld specimen shows predominately martensitic phase in the weld region, whereas the autogenous weld shows lathy ferrite mixed with martensitic phase. Mechanical test results indicated that filler welded specimen (ER316L and ER309L) has relatively higher strength and hardness than the autogenous weld, whereas ER316L filler weld exhibited the highest impact toughness than ER309L filler weld and lowest in autogenous weld. The electrochemical corrosion results displayed the highest degree of sensitization (DOS) in without filler welded specimen (45.62%) and lower in case of filler welded specimen ER309L (4.95%) and least in case of ER316L filler welded specimen (3.51%). The high DOS in non-filler welded specimen is correlated with the chromium carbide formation. The non-filler welded specimen shows the highest pitting corrosion attack as compared to the ER316L filler weld specimen and relatively better in ER309L filler welded specimen. The highest pitting corrosion resistance is related with the high chromium content in ER309L composition.

This experimental study is original and conducted with 316L and 430 stainless steel with ER316L, ER309 and without fillers, which will help the oil, shipbuilding and chemical industries.

Regarding how the public regulation of human services is perceived within welfare organizations and how the latter cope with it, the role of emotions (as mediators between structure and agency) proves highly relevant while often being hidden beneath the surface. This article shows how a specific approach to such regulation – here: managerialism – may impact on “emotional regimes” at the organizational and individual level, affecting the attainment of organizational goals and workers' health.

The article primarily draws on multiple qualitative case studies across two welfare sectors (four organizations) in Germany (continuing education/active inclusion; long-term care). The study research was conducted between 2020 and 2022 and based on 36 interviews with caseworkers and managers, focus group interviews and expert dialogues at industry level.

The results suggest that the managerialist regulation of welfare services breeds complex and ambiguous emotional regimes. Business-like management techniques elicit various emotions, affecting the motivational basis of human service work. While the experience of hard challenges may raise positive feelings, coping patterns often put strain on organizations and staff alike. In the short run, related emotional regimes tend to make service delivery proceed smoothly, yet in the long run they may have corrosive effects and problematic repercussions on macro-level developments.

The study highlights the role of emotions in publicly regulated human service settings by intermingling macro- and micro-level processes and thereby broadens the perspective of welfare state research as it reveals the impact of (managerialist) regulation on the dynamic organizational chemistry of such settings.

Gas transmission pipelines are at constant risk of gas leakage or fire due to various atmospheric environments, corrosion on pipe metal surfaces and other external factors. This study aims to reduce the human and financial risks associated with gas transmission by regularly monitoring pipeline performance, controlling situations and preventing disasters.

Facility managers can monitor the status of gas transmission lines in real-time by integrating sensor information into a building information modeling (BIM) 3D model. Using the Monitoring Panel plugin, coded in C# programming language and operated through Navisworks software, the model provides up-to-date information on pipeline safety and performance.

By collecting project information on the BIM and installing critical sensors, this approach allows facility manager to observe the real-time safety status of gas pipelines. If any risks of gas leakage or accidents are identified by the sensors, the BIM model quickly shows the location of the incident, enabling facility managers to make the best decisions to reduce financial and life risks. This intelligent gas transmission pipeline approach changes traditional risk management and inspection methods, minimizing the risk of explosion and gas leakage in the environment.

This research distinguishes itself from related work by integrating sensor data into a BIM model for real-time monitoring and providing facility managers with up-to-date safety information. By leveraging intelligent gas transmission pipelines, the system enables quick identification and location of potential hazards, reducing financial and human risks associated with gas transmission.

This paper aims to achieve an anti-corrosive coating via uniform dispersion of nanoclay particles (montmorillonite) and polypyrrole (PPy) as a conductive polymer as well as their effects on the anti-corrosion features in the presence of the eco-friendly ionic liquids (ILs).

In this research, PPy with different forms of nanoclay were used. Moreover, ILs additive is used to enhance the better dispersion process of clay and PPy nanoparticles in the resin.

As a result, the IL additive in the formulation of nano-composite coatings greatly improves the dispersion process of clay and PPy nanoparticles in the resin. Due to its high compatibility with polyurethane resin and clay and PPy nanoparticles, this additive contains a high dispersing power to disperse the investigated nanoparticles in the resin matrix.

High polarity of ILs as well as abilities to dissolve both mineral and organic materials, they can provide the better chemical processes compared to common solvents.

IL abilities have not been discovered to a large extent such as catalysts and detectors.

ILs have been emerging as promising green solvents to replace conventional solvents in recent years. They possess unique properties such as nonvolatility, low toxicity, ease of handling, nonflammability and high ionic conductivity. Thus, they have received much attention as green media for various chemistry processes.

The simultaneous existence of clay, PPy and IL additive in the nano-composite coating formulation is responsible for the high corrosion resistance of the coating.

This paper covers the development of a novel defect model for concrete highway bridges. The proposed defect model is intended to facilitate the identification of bridge’s condition information (i.e. defects), improve the efficiency and accuracy of bridge inspections by supporting practitioners and even machines with digitalised expert knowledge, and ultimately automate the process.

The research design consists of three major phases so as to (1) categorise common defect with regard to physical entities (i.e. bridge element), (2) establish internal relationships among those defects and (3) relate defects to their properties and potential causes. A mixed-method research approach, which includes a comprehensive literature review, focus groups and case studies, was employed to develop and validate the proposed defect model.

The data collected through the literature and focus groups were analysed and knowledge were extracted to form the novel defect model. The defect model was then validated and further calibrated through case study. Inspection reports of nearly 300 bridges in China were collected and analysed. The study uncovered the relationships between defects and a variety of inspection-related elements and represented in the form of an accessible, digitalised and user-friendly knowledge model.

The contribution of this paper is the development of a defect model that can assist inexperienced practitioners and even machines in the near future to conduct inspection tasks. For one, the proposed defect model can standardise the data collection process of bridge inspection, including the identification of defects and documentation of their vital properties, paving the path for the automation in subsequent stages (e.g. condition evaluation). For another, by retrieving rich experience and expert knowledge which have long been reserved and inherited in the industrial sector, the inspection efficiency and accuracy can be considerably improved.

Despite endeavors to alleviate construction and demolition waste and the indications that the process of deconstruction has the potential to steer waste reduction initiatives, there has not been a progressive increase in the adoption of Design for Deconstruction (DfD) in the global south, especially Ghana. This paper aims to identify and analyze the barriers to implementing DfD in developing countries.

A structured questionnaire survey was used to solicit the views of 240 design professionals in the Ghanaian construction industry (GCI). The questionnaire was developed by reviewing pertinent literature and complemented with a pilot review. Data were analyzed using descriptive and nonparametric statistics.

The findings revealed ten (10) significant impediments to implementing DfD within the construction industries in developing economies. These impediments revolve around cost, legal matters, storage, incentive and design-related matters. Key among these barriers is “For recovered materials, there are little performance guarantees,” “The absence of strict regulations regarding design for deconstruction,” “Lack of a large market enough for components that have been recovered,” “The need for building codes that address how to design with reused materials” and “Lack of effective design for deconstruction tools.”

The results of this research shed light on a relatively unexplored area within the construction sector, particularly in a developing country like Ghana. Furthermore, to the best of the authors’ knowledge, the study contributes fresh and supplementary knowledge and perspectives regarding the challenges in implementing DfD practices.

Industrial heritage is considered an essential part of cultural heritage in the world. This heritage suffers from continued marginalisation in the Arab world, particularly in Jordan, where many industrial heritage sites have not been protected or studied well due to the lack of a clear definition of cultural heritage. Most of these sites, built in the 20th century, are gradually disappearing or scheduled for demolition. This paper explores the de-industrialisation discourse and the loss of modern industrial heritage in the Arab world, especially in Jordan.

This research investigates the modern industrial heritage in Jordan as a case study in the Arab world. A comprehensive understanding of the industrial heritage has been obtained by adopting a case study approach and using a reconnaissance survey of potential industrial heritage sites in Jordan.

Seven categories were used in the analysis of the de-industrialisation phenomenon of heritage sites: ownership, location, design and types; structure, significance, deterioration and physical condition and conservation attempts and alterations. Three main approaches to industrial heritage were identified: demolition, occasional maintenance and rare examples of conservation and adaptive reuse.

This study sheds light on the ownership issue of industrial structures in Jordan and invites policymakers, relevant authorities, private organisations and the public to consider the challenges and impact of de-industrialisation of such sites.

This research raises awareness of the de-industrialisation discourse, and highlights the value of industrial architecture dating back to the modernity period, which was short-lived in Jordan. It also calls for serious consideration of these sites to support sustainable development in the Arab World.

This research investigates the distinct characteristics of blockchain technology to safeguard against the deterioration of handover information quality in the post-construction phase. The significance of effective management of handover information is highlighted by global building failures, such as the Grenfell Tower fire in London, UK. Despite existing technological interventions, there remains a paucity of understanding regarding the factors contributing to the decline in the quality of handover information during the post-construction phase.

This study employed a multi-case studies approach across five higher education institutions. It involved conducting semi-structured interviews with 52 asset management professionals, uncovering the underlying reasons for the decline in handover information quality. Building on these insights, the study performed a mapping exercise to align these identified factors with blockchain technology features and information quality dimensions, aiming to evaluate blockchain’s potential in managing quality handover information.

The study findings suggest that blockchain technology offers advantages but has limitations in addressing all the identified quality issues of managing handover information. Due to the lack of an automated process and file-based information exchange, updating handover information still requires an error-prone manual process, leading to potential information loss. Additionally, no solutions are available for encoding drawings for updates and validation.

This study proposes a framework integrating blockchain to enhance the information management process and improve handover information quality.