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The aim of this paper is to determine the thermal conductivity of a protective layer of alkali-activated cement and the possibility of performing fire protection with fireclay sand and Lightweight mortar. Unprotected steel structures have generally low fire resistance and require surface protection. The design of passive protection of a steel element must consider the service life of the structure and the possible need to replace the fire protection layer. Currently, conventional passive protection options include intumescent coatings, which are subject to frequent inspection and renewal, gypsum and cement-based fire coatings and gypsum and cement board fire protection.

Alkali-activated cements provide an alternative to traditional Portland clinker-based materials for specific areas. This paper presents the properties of hybrid cement, its manufacturability for conventional mortars and the development of passive fire protection. Fire experiments were conducted with mortar with alkali-activated and fireclay sand and lightweight mortar with alkali-activated cement and expanded perlite. Fire experiment FE modelling.

The temperatures of the protected steel and the formation of cracks in the protective layer were investigated. Based on the experiments, the thermal conductivities of the two protective layers were determined. Conclusions are presented on the applicability of alkaline-activated cement mortars and the possibilities of applicability for the protection of steel structures. The functionality of the passive fire layer was confirmed and the strengths of the mortar used were determined. The use of alkali-activated cements was shown to be a suitable option for sustainable passive fire protection of steel structures.

Eco-friendly fire protection based on hybrid alkali-activated cement of steel members.

The extreme nature of fire makes structural fire engineering unique in that the load actions dictating design are intense and neither geographically nor seasonally bound. Simply, fire can break out anywhere, at any time and for any number of reasons. Despite the apparent need, the fire design of structures still relies on expensive fire tests, complex finite element simulations and outdated procedures with little room for innovation. This paper aims to discuss the aforementioned issues.

This primer highlights the latest state of the art in this area with regard to performance-based design in fire structural engineering. In addition, this short review also presents a series of examples of successful implementation of performance-based fire design of structures from around the world.

A comparison between global efforts clearly shows the advances put forth by European and Oceanian efforts as opposed to the rest of the world. In addition, it can be clearly seen that most performance-based fire designs are related to steel and composite structures.

In one study, this paper presents a concise and global view to performance-based fire design of structures from success stories from around the world.

Steel-reinforced concrete-filled steel tubular (SRCFST) columns have been increasingly popular in engineering practice for the columns' excellent seismic and fire performance. Significant design progress guidance has been made through continuous numerical and experimental research in recent years. This paper tested and analysed the residual loading capacity of SRCFST columns under axial loading after experiencing non-uniform ISO-834 standard fire.

The experimental research covered the main parameter of heating conditions, 1-side and 2-side fire, through two specimens. Two specimens were heated and loaded simultaneously in the furnace for 240 min. After cooling, the columns were moved to the hydraulic loading system and loaded to failure to determine the columns' residual capacity.

The experimental results indicated that the non-uniform heating area plays an essential role in the overall performance of SRCFST columns, the increasing heating area of columns results in lower residual loading capacity and stiffness. The SRCFST columns still had a high loading capacity after heating and loading in the fire.

The comparison of experimental data against design results showed that the design method generated a 16% safety margin for S2H4 and a 39% safety margin for S1H4.

This study describes a series of experiments investigating the upper hot layer temperature profile in a confined space under different ventilation conditions for porosity-controlled wood crib fires for pre-flashover conditions.

Full-scale compartment (4 m × 4 m × 4 m) experiments were carried out for four-door openings, i.e. 100%, 75%, 50% and 25% of the total vent area (2 m × 1 m) with the wood crib as a fuel load. The temperature of the upper hot smoke layers of the compartment was recorded with the help of four layers of thermocouples for varying vent areas.

The effect of ventilation on the properties, i.e. mass loss rate, enclosure temperature, heat release rate and carbon monoxide (CO) gas concentration, has been measured and analyzed. The effect of ventilation on heat flux and flame temperature has also been studied. Compartment gas temperature has been examined by five wood crib burning stages: Ignition, growth, steady burning, recess and collapse.

Findings demonstrate that the influence of vent openings varies for the burning parameters and upper layer temperature of the compartment. The current results are beneficial in analyzing thermal risks concerning compartment fire and fire safety engineering projects.

To elaborate the nature of fact-checking in the domain of political information by examining how fact-checkers assess the validity of claims concerning the Russo-Ukrainian conflict and how they support their assessments by drawing on evidence acquired from diverse sources of information.

Descriptive quantitative and qualitative content analysis of 128 reports written by the fact-checkers of Snopes – an established fact-checking organisation – during the period of 24 February 2022 – 28 June, 2023. For the analysis, nine evaluation grounds were identified, most of them inductively from the empirical material. It was examined how the fact-checkers employed such grounds while assessing the validity of claims and how the assessments were bolstered by evidence acquired from information sources such as newspapers.

Of the 128 reports, the share of assessments indicative of the invalidity of the claims was 54.7%, while the share of positive ratings was 26.7%. The share of mixed assessments was 15.6%. In the fact-checking, two evaluation grounds, that is, the correctness of information and verifiability of an event presented in a claim formed the basis for the assessment. Depending on the topic of the claim, grounds such as temporal and spatial compatibility, as well as comparison by similarity and difference occupied a central role. Most popular sources of information offering evidence for the assessments include statements of government representatives, videos and photographs shared in social media, newspapers and television programmes.

As the study concentrated on fact-checking dealing with political information about a specific issue, the findings cannot be extended to concern the fact-checking practices in other contexts.

The study is among the first to characterise how fact-checkers employ evaluation grounds of diverse kind while assessing the validity of political information.

The paper aims to deal with the enhancement of a simplified method for the design of concrete columns subject to fire toward applications on circular and tubular cross-sections. The original zone method, developed by Hertz as a plastic design method, has been extended by Achenbach for the use as a nonlinear method. This proposed extended zone method (EZM) is verified by checking the theoretical background and is successfully validated by the recalculation of laboratory tests.

The zone method assumes a reduction of a cross-section by a “damaged” zone. The remaining area is modeled with the constant, temperature-dependent material properties. The equations for the calculation of the damaged zone to model the loss of cross-section resistance or stiffness are derived. The proposed equations are validated by the recalculation of laboratory test and compared to the results of the advanced method (AM).

It can be shown that the EZM is suitable for the check of the fire resistance of circular concrete columns and leads to a safe and economic design. The method provides a suitable alternative to more sophisticated AM. The further extension toward tubular spun columns is discussed und is the object of the ongoing research.

Presented enhancement extends the range of applications of the EZMs toward circular and tubular cross sections, which has previously not been examined.

Through the scientific and reasonable evaluation of the site selection of the emergency material reserve, the optimal site selection scheme is found, which provides reference for the future emergency decision-making research.

In this paper, we have chosen three primary indicators and twelve secondary indicators to construct an assessment framework for the determination of suitable locations for storing emergency material reserves. By mean of the improved entropy weight-order relationship weight determination method, the evaluation model of kullback leibler-technique for order preference by similarity to an ideal solution (KL-TOPSIS) emergency material reserve location based on relative entropy is established. On this basis, 10 regional storage sites in Beijing are selected for evaluation.

The results show that the evaluation model of the location of emergency material reserve not only respects the objective knowledge, but also considers the subjective information of the experts, which makes the ranking result of the location of the emergency material reserve more accurate and reliable.

Firstly, the modification factor is added to the calculation formula of traditional entropy weight method to complete the improvement of entropy weight method. Secondly, the order relation analysis method is used to assign subjective weights to the indicators. The principle of minimum information entropy is introduced to determine the comprehensive weight of the index. Finally, KL distance and TOPSIS method are combined to determine the relative entropy and proximity degree of alternative solutions and positive and negative ideal solutions, and the scientific and effective of the method is proved by case study.

This paper aims to review and assess the sustainable design and management considerations affecting workplaces’ productivity in Saudi Arabia.

The study uses a mixed approach, commencing with literature review, development and pilot-testing of a structured questionnaire instrument to assess design and management considerations towards productively sustainable workplaces (PSWs). In total, 31 considerations affecting sustainable workplaces’ productivity were identified and clustered under five main directions. A collective group of stakeholders, including architects/engineers (A/E), workplace users and facilities managers, were approached to correlate and compare their individual assessment of the identified PSWs. The relative importance index (RII) for each of the PSW considerations is correlated and discussed.

A high level of agreement is recognized among the three stakeholder groups for PSWs considerations’ assessed rankings. The provision of sufficient ventilation and illumination levels, availability of occupational health, security and safety, availability of ergonomically oriented technological infrastructure, availability of formal and informal meeting spaces, efficient space utilization and ergonomic workstations are all ranked highest in importance as design considerations towards PSWs.

The study stems from the need to understand how the PSWs’ design and management considerations are perceived by all streams of stakeholders. The findings identify the considerations’ importance for prioritization on PSWs’ investments.

Providing high-quality and cost-efficient care of older people is an important development priority for many health and social care systems in the world. This paper suggests a shift from acute, episodic and reactive hospital-centered care toward longitudinal, person-centered and proactive home-centered care. The purpose of this paper is to contribute to the knowledge of a comprehensive development strategy for designing and providing home-centered care of older people.

The study design is based on qualitative research with an inductive approach. The authors study development initiatives at the national, regional and local levels of the Swedish health and social care system. The data collection methods included interviews (n = 54), meeting observations (n = 25) and document studies (n = 59).

The authors describe findings related to policy actions and system changes, attempts to achieve collaboration, integration and coordination, new forms of care offerings, characteristics of work settings at home and differences in patients' roles and participation at home and in the hospital.

The authors suggest home-centered care as a solution for providing person-centered and integrated care of older people and give examples of how this can be achieved.

The authors outline five propositions for research and development related to national policies, service modularity as a solution for customized and coordinated care, developing human resources and infrastructure for home settings, expanding services that enable older people living at home and patient co-creation.