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This paper aims to inspect the effect of indirect elevated temperature on the mechanical performance of nano silica concrete (NSC). The effect on both compressive and bond strengths is studied. Pre- and post-exposure to elevated temperature ranges of 200 to 600°C is examined. A range covered by three percentages of 1.5, 3 and 4.5 per cent nano silica (NS) in concrete mixes is tested.

Pre-exposure mechanical tests (normal conditions – room temperature), using 3 per cent NS in the concrete mix, led to the highest increase in both compressive and bond strengths (43 per cent and 38.5 per cent, respectively), compared to the control mix without NS (based on 28-day results). It is worth noticing that adding NS to the concrete mixes does not have a significant effect on improving early-age strength. Besides, permeability tests are performed on NSC with different NS ratios. NS improved the concrete permeability for all tested percentages of NS. The maximum reduction is accompanied by the maximum percentage used (4.5 per cent NS in the NSC mix), reducing permeability to half the value of the concrete mix without NS. As for post-exposure to elevated-temperature mechanical tests, NSC with 1.5 per cent NS exhibited the lowest loss in strength owing to indirect heat exposure of 600°C; the residual compressive and bond strengths are 73 per cent and 35 per cent, respectively.

The dispersion technique of NS has a key role in NSC-distinguished mechanical performance with NSC having lower NS percentages. NS significantly improved bond strength. NS has a remarkable effect on elevated temperature endurance. The bond strength of NSC exposed to elevated temperatures suffered faster deterioration than compressive strength of the exposed NSC.

A special scale factor needs to be investigated for the NSC.

Although a lot of effort is placed in evaluating the benefits of using nano materials in structural concrete, this paper presents one of the first outcomes of the thermal effects on concrete mixes with NS as a partial cement replacement.

Nano-Clay (NC) is reported as a candidate partial replacement for cement, due to its abundance and relatively low cost - beside reported promotion of different concrete properties. On the other hand, Steel Fibres (SF) has proven to have a positive effect on post fire exposure residual strength of concrete. This paper aims to present the outcomes of a comprehensive research program assessing a hybrid mix between NC and SF in concrete mixtures (NCSF-CRETE).

Physical chemical and physical characterization of NC is performed using different tools as XRF spectrometer, and TEM micrograph. Fresh concrete properties of NSCF-CRETE as slump and air content are investigated. Enhancement in permeability using NSCF is verified by comparing its resistance to the penetration of chlorides resistance with regular concrete mix. Besides, the proposed NCSF-CRETE compressive strength is evaluated compared to mixes with NC and SF each used separately at different curing ages. Besides, NSCF and compared mixes are exposed to an indirect fire testing program – two hours exposure – for: 300, 450 and 600°C. Degradation in compressive strength was investigated after exposure to different temperatures and percentage of residual strength is reported.

Results indicated an improved performance of NCSF -CRETE of about 40% compared to regular concrete in compressive strength at normal conditions. This improvement extended to its behavior when subjected to indirect fire exposure NSCF also maintained 40% more strength than the residual in regular concrete mix – which suffered severe damage – after 2 h exposure to 600°C.

Using NCSF-Crete allows retrofitting the structure after exposure to such drastic conditions.

Change orders in construction projects may lead to an increase in time and cost highlighting the need for a systematic analysis of the causes of change orders. Each cause of change orders has a probability of occurrence and impact; therefore, there is a need to reassess the causes of change orders based on the probability and impact. The purpose of this paper is to determine the risk score for each factor and develop a model for estimating the overall change orders based on the measured and latent variables.

The research methodology consists of four parts. The first part identifies the causes of change orders in road projects from a literature review and develops the final list using the Delphi technique. The second part includes designing the final questionnaire to determine the probability and impact of each factor on the five-point Likert scale and 237 questionnaires received validity. The data were divided into training and testing sets and analyzed using AMOS software.

The proposed structural equation model presents an insight into the influence of measured and latent factors, which are not obvious in the traditional equations. The main cause for change orders was a change in design.

The results of this research are expected to improve the execution of road projects by identifying the main causes of the change orders and hence the project manager can develop a proper risk response plan.

This paper presents the second part of the investigation on resistance to elevated temperatures of a proposed hybrid composite concrete (NCSF-Crete) mix. The composite including nano metakaolin (NC) and steel fibers (SF) in addition to regular concrete components has proven -in the first published part-earlier promoted fresh concrete behavior, and to have reduced loss in compressive strength after exposure to a wide range of elevated temperatures. This presented work evaluates another two critical mechanical characteristics for the proposed composite -namely- splitting and bond strengths.

A modified formula correlating splitting and compressive strength (28 days) based on experiments results for NCSF is proposed and compared to formulas derived for regular concrete in different design codes. Finally, both spitting and bond strengths are evaluated pre- and post-exposure to elevated temperatures reaching 600 °C for two hours.

The proposed NCSF-Crete shows remarkable fire endurance, especially in promoting bond strength as after 600 °C heat exposure tests, it maintained strength equivalent to 70% of a regular concrete control mix at room temperature. Improving residual splitting strength was very significant up to 450 °C exposure.

Obvious deterioration is monitored in splitting resistance for all concretes at 600 °C.

This proposed composite improved elevated heats resistance of the most significant concrete mechanical properties.

Using a more green and sustainable constituents in the composite.

The proposed composite gathers the merits of using NC and SF, each has been investigated separately as an addition to concrete mixes.

The purpose of this paper is to explore the “event” of the construction of Naguib Mahfouz Square. Drawing on the memory of Gamaet-Aldowel-AlArabyia Street, it attempts to uncover the socio-cultural structures inherited in the Egyptian urban street.

This study adopts Foucauldian discourse on institutions of “knowledge and authority” to approach the power relations between the actors involved. This discourse was constructed through in-depth, unstructured interviews with architects and involved government personnel as well as other archival resources that included national newspapers and magazines.

This discourse reflected an institutional controversy between these actors over the perception and design of the Egyptian street, highlighting the alienation of the designer, and the user/lay-people, from the urban institution. Naguib Mahfouz Square presented a considerable deviation from the established norms of street design in Egypt at that time through its commemoration of a contemporary figure in literature, the architect’s involvement in the design process and the unfencing of urban space. This event thus questions the perception of the urban street beyond our socio-cultural inheritance, and towards street design as a performative urban act that embraces the everyday activities of lay-people in the street.

The paper utilises Foucauldian discourse on power to approach a case study of an urban event and space in Egypt, which has not previously been investigated thoroughly. It thus holds potential towards the resolution of inherited conflict between the urban street and the urban institution.

Current processes to manage changes are subject to failure since they are heavily dependent on human discipline. The purpose of this paper is to evaluate and quantify the difference between levels of automation of change management processes and to provide input for determining the use of automation systems for change management.

Three generations of change management processes are defined to represent progressive practices used in major capital projects over the past few decades. Discrete event simulation was used to model these processes to capture their behavior and compare their performance according to time and compliance metrics. An oil and gas megaproject served to validate the findings of this modeling and analysis.

The results showed that automated processes can bring more compliance and real-time traceability, but not a significant time reduction in the change process. This contributes to the understanding of the impact of workflow-based automation on construction process performance. The validity of the conclusions are limited by the breadth of sectors studied and the inability to capture off-line time allocations of the personnel involved. Future research may build on the work presented here by studying additional processes such as requests for information, project change notices, requests for scaffolding, and interface management in various industry sectors.

A new approach for modeling and evaluating construction management process automation is contributed and the specific results of the paper indicate that automated workflow-based change management processes should be implemented in megaprojects.

Nowadays, the digitized economy and technological advancements are increasing at a faster pace. One such technology that is gaining popularity in the healthcare sector is Artificial Intelligence (AI). AI has been debated much, searched so well due to the implications, issues and for its benefits in terms of ease, it will offer. The following research has focused on examining the ethical dilemmas associated with AI when it will be introduced in the healthcare sector.

A narrative review method focusing on content analysis has been used in the research. The authors have employed a deductive approach to determine the ethical facets of adopting AI in the healthcare sector. The current study is complemented by a review of related studies. The secondary data have been collected from authentic resources available on the Internet.

Patient privacy, biased results, patient safety and Human errors are some major ethical dilemmas that are likely to be faced once AI will be introduced in healthcare. The impact of ethical dilemmas can be minimized by continuous monitoring but cannot be eliminated in full if AI is introduced in healthcare. AI overall will increase the performance of the healthcare sector. However, we need to address some recommendations to mitigate the ethical potential issues that we could observe using AI. Technological change and AI can mimic the overall intellectual process of humans, which increases its credibility and also offers harm to humans.

Patient safety is the most crucial ethical concern because AI is a new technology and technology can lead to failure. Thus, we need to be certain that these new technological developments are ethically applied. The authors need to evaluate and assess the organizational and legal progress associated with the emergence of AI in the healthcare sector. It also highlights the importance of covering and protecting medical practitioners regarding the different secondary effects of this artificial medical progress. The research stresses the need of establishing partnerships between computer scientists and clinicians to effectively implement AI. Lastly, the research highly recommends training of IT specialists, healthcare and medical staff about healthcare ethics.

The study aims to tackle Egypt's rising electricity consumption due to climate change and population growth, focusing on the building sector, which accounts for up to 60% of the issue, by developing new energy-efficient design guidelines for Egyptian buildings.

This study comprises six key steps. A literature review focuses on energy consumption and efficiency in buildings, monitoring a single-family building in Cairo, using Energy Plus for simulation and verification, performing multi-objective optimization, comparing energy performance between base and controlled cases, and developing a localized version of the Passive House (PH) called Energy Efficiency Design Criteria (EEDC).

The research shows that applying the (EEDC) suggested by this study can decrease energy consumption by up to 58% and decrease cooling consumption by up to 63% in residential buildings in Egypt while providing thermal comfort and reducing greenhouse gas emissions. This can benefit users, alleviate local power grid strain, contribute to Egypt's economy, and serve as a model for other countries with similar climates.

To date, no studies have focused on developing energy-efficient design standards tailored to the Egyptian climate and context using the Passive House Criteria concept. This study contributes to the field by identifying key principles, design details, and goal requirements needed to promote energy-efficient design standards for residential buildings in Egypt.