Search Results (245)

Blast mitigation of structures is an important research topic due to increasing intentional and accidental human-induced threats and hazards. This research area is essential to building capabilities in sustaining structural protection, site planning, protective design efficiency, occupant safety, and response and recovery plans. This paper investigates experimental tests and finite element analysis (FEM) of thin A36 steel sheets subjected to blast. Six field blast tests were performed at standoff distances of 300 mm and 500 mm. The explosive charges comprised 334 g of bare Composition B, and the steel sheets were 2 mm thick. The experimental results, derived from the analysis of high-speed camera recordings of the blast events, were compared with FEM simulations conducted using Abaqus^®/Explicit version 6.10. Three constitutive material models were considered in these simulations. First, the FEM simulation results were compared with experimental results. It was shown that the FEM analysis provided reliable results and was proven to be robust and cost-effective. Second, an extensive set of 460 additional numerical simulations was carried out as a parametric study involving varying standoff distances and steel sheet thicknesses. The results and methodologies presented in this paper offer valuable and original insights for engineers and researchers aiming to predict damage to steel structures during real detonation events and to design blast-resistant structures. Full article

This study investigates the use of waste glass powder derived from fluorescent lamps as a partial replacement for cement in mortar production, aiming to valorize this Waste from Electrical and Electronic Equipment (WEEE) and enhance sustainability in the construction sector. Mortars were formulated by substituting 25% of cement by volume with glass powders from fluorescent lamp glass and green bottle glass. The experimental program evaluated mechanical strength, durability parameters and ecotoxicological performance. Results revealed that clean fluorescent lamp mortars showed the most promising mechanical behavior, exceeding the reference in long-term compressive (54.8 MPa) and flexural strength (10.0 MPa). All glass mortars exhibited significantly reduced chloride diffusion coefficients (85–89%) and increased electrical resistivity (almost 4 times higher), indicating improved durability. Leaching tests confirmed that the incorporation of fluorescent lamp waste did not lead to hazardous levels of heavy metals in the cured mortars, suggesting effective encapsulation. By addressing both technical (mechanical and durability) and ecotoxic performance, this research contributes in an original and relevant way to the development of more sustainable building materials. Full article

Historical buildings are exposed to an increased risk of fire. The direct influence comes from the buildings’ structural design and the fire protection level. The fundamental principle for reducing the loss of heritage value in historical buildings due to fire is fire protection, as part of crisis management. This article focuses on selected castle buildings from Slovakia. Three castle buildings were selected based on their location in the country. All of them are currently used for museum purposes. Using an analytical form, we assessed fire hazards and fire safety measures in two parts, calculated the fire risk index, and proposed solutions. Qualitative research, which is more suitable for the issue at hand, was used to evaluate the selected objects. The main methods used in the research focused on visual assessment of the current condition of the objects and analysis of fire documentation and its comparison with currently valid legal regulations. Based on the results, we can conclude that Kežmarok Castle (part of the historical city center) has a small fire risk (fire risk index = 13 points). Trenčín Castle (situated on a rock above the city) and Stará Ľubovňa Castle (situated on a limestone hill outside the city, surrounded by forest) have an increased risk of fire (fire risk index = 50–63). Significant risk sources identified included surrounding forest areas, technical failures related to outdated electrical installations, open flames during cultural events, the concentration of highly flammable materials, and complex evacuation routes for both people and museum collections. Full article

A novel unified progressive hybrid censoring is introduced to combine both progressive and hybrid censoring plans to allow flexible test termination either after a prespecified number of failures or at a fixed time. This work develops both frequentist and Bayesian inferential procedures for estimating the parameters, reliability, and hazard rates of the inverted Nadarajah–Haghighi lifespan model when a sample is produced from such a censoring plan. Maximum likelihood estimators are obtained through the Newton–Raphson iterative technique. The delta method, based on the Fisher information matrix, is utilized to build the asymptotic confidence intervals for each unknown quantity. In the Bayesian methodology, Markov chain Monte Carlo techniques with independent gamma priors are implemented to generate posterior summaries and credible intervals, addressing computational intractability through the Metropolis—Hastings algorithm. Extensive Monte Carlo simulations compare the efficiency and utility of frequentist and Bayesian estimates across multiple censoring designs, highlighting the superiority of Bayesian inference using informative prior information. Two real-world applications utilizing rare minerals from gold and diamond durability studies are examined to demonstrate the adaptability of the proposed estimators to the analysis of rare events in precious materials science. By applying four different optimality criteria to multiple competing plans, an analysis of various progressive censoring strategies that yield the best performance is conducted. The proposed censoring framework is effectively applied to real-world datasets involving diamonds and gold, demonstrating its practical utility in modeling the reliability and failure behavior of rare and high-value minerals. Full article

Wildlife strikes in aviation are among the most reported safety incidents. As such, strikes have become the fundamental unit of understanding of the risk posed by wildlife. However, the management of wildlife risks to aviation has shifted to a hazard management philosophy. This literature review examines the argument that current wildlife strike reporting requirements are inadequate for modern wildlife hazard management techniques. This review utilised bibliometric analysis software to identify relevant academic research sourced from the Web of Science, as well as industry materials, to compile a final catalogue (n = 542). Further filtering revealed a limited set of relevant papers (n = 42) and even fewer papers that addressed the above question. Analysis of these papers and the wider catalogue noted limitations in current reporting requirements as they relate to hazard and risk management concepts. This analysis was supplemented with a review of international standards and relevant national requirements, concluding that while academics and industry have adopted systematic safety and hazard management techniques, and international guidance material has kept pace, international standards, the foundation for many national reporting systems, remain decades behind. This paper proposes the use of robust consensus-building methodologies, such as the Delphi technique, in the industry as a means of streamlining and supporting international standards development. Full article

This study evaluates the accuracy of ²²²Rn exhalation rates from building materials using two standard experimental protocols, thus addressing the increasing importance of rapid radon assessment due to health concerns and regulatory limits. In detail, six types of natural stones frequently employed for the construction of buildings of historical-artistic relevance were analyzed using the closed chamber method (CCM) combined with the Durridge Rad7 system, by using two experimental protocols that differed in the measurement duration: 10 days (Method 1) versus 24 h (Method 2). Obtained results revealed that the radon exhalation rates ranged from 0.004 to 0.072 Bq h⁻¹, which are moderate to low if compared to studies in other regions. Statistical comparison using the u-test confirmed equivalence between protocols (u-test ≤ 2), thus supporting the validity of the faster Method 2 for practical applications. Furthermore, to estimate the potential indoor radon levels and determine the associated radiological risks to human health, for the investigated natural stones, the Markkanen room model was employed. As a result, simulated indoor radon concentrations remained well below regulatory thresholds (maximum value: 37.3 Bq m⁻³), thus excluding any significant health concerns under typical indoor conditions. Full article

The analysis of the vulnerability of vernacular buildings to climatic hazards is nowadays a subject of significant importance due to the consequences of climate change. This study assesses the vulnerability of vernacular buildings to three climatic hazards (heavy rains, strong winds and high heat) in the Kara region to identify the vulnerable parts of these constructions that require reinforcement. It is based on PTVA (Papathoma Tsunami Vulnerability Assessment), a multi-hazard analysis methodology, which uses vulnerability indicators. It focuses on the Kabiyè and Nawdeba peoples, who are the major ethnic groups in the region. Focus groups with the population, interviews with professionals and a series of surveys of 125 households in the visited territories enabled us to identify, firstly, the types of vernacular constructions in the region, the climatic hazards that occur there and the indicators that affect the vulnerability of the constructions. Secondly, we calculated the vulnerability index for each type of construction to the three climatic hazards. The vulnerability index of Kabiyè vernacular architecture (KVA) to heavy rain, high heat and strong wind is 0.379, 0.403 and 0.356, respectively. The Nawdéba vernacular architecture (NVA) vulnerability score is 0.359 for heavy rain, 0.375 for high heat, and 0.316 for strong wind. The index of vulnerability to heavy rain, high heat and strong wind for contemporary architecture (CA), as we term the current state of evolution of these two forms of architecture, is 0.499, 0.522 and 0.456, respectively. This study reveals that contemporary architecture (CA) in the Kara region, regardless of the type of hazard considered, is the most vulnerable construction model in the region. It also highlights the indicators that accentuate the vulnerability of vernacular constructions. Regardless of the type of construction, special attention must be paid to features such as roof style (roof slope, shape and material) and building style (form and state of maintenance of the building) to increase the resilience of buildings to climatic hazards. Full article

Renewable energy sources are presented as a key solution to today’s energy needs, but they also generate waste that can have a negative impact on the environment. In particular, fly ash from the incineration of municipal solid waste (MSW), classified as hazardous by European regulations, is often deposited in landfills due to its lack of usefulness. This research proposes its valorisation in geopolymers, combining it with mining to create a sustainable material with a high industrial waste content. Firstly, all the wastes involved were characterised, which allowed for the development of a high-quality geopolymer from mining residue activated with 5% NaOH. This material was enriched with up to 50% fly ash (in increasing percentages) with the aim of making it inert, retaining it in the geopolymer matrix, and observing its effect on the final material. The physical and mechanical properties of the geopolymers obtained were evaluated, demonstrating that they do not produce contaminating leachates. The results indicate the feasibility of developing a geopolymer with up to 20% fly ash, obtaining a building material comparable to traditional ceramics, suitable for commercialisation, with a lower environmental impact and in line with the principles of the circular economy. Full article

The combustion of hard coal and lignite in power and combined heat and power plants generates significant amounts of coal fly ash (CFA), a waste material with variable properties. CFA naturally contains radionuclides, specifically naturally occurring radioactive materials (NORMs), which pose potential radiological risks to the environment and human health during their storage and utilization, including their incorporation into building materials. Although global research on the radionuclide content in CFA is available, there is a clear gap in detailed and current data specific to Central and Eastern Europe and notably, a lack of a systematic analysis investigating the influence of installed power plant capacity on the concentration profile of these radionuclides in the generated ash. This study aimed to fill this gap and provide crucial data for the Polish energy and environmental context. The objective was to evaluate the concentrations of selected radionuclides (²³²Th, ²²⁶Ra, and ⁴⁰K) in coal fly ash samples collected between 2020 and 2023 from 19 Polish power and combined heat and power plants with varying capacities (categorized into four groups: S1–S4) and to assess the associated radiological risk. Radionuclide concentrations were determined using gamma spectrometry, and differences between groups were analyzed using non-parametric statistical methods, including PERMANOVA. The results demonstrated that plant capacity has a statistically significant influence on the concentration profiles of thorium and potassium but not radium. Calculated radiological hazard assessment factors (Ra_eq, H_ex, H_in, IAED) revealed that although most samples fall near regulatory limits (e.g., 370 Bq kg⁻¹ for Ra_eq), some exceed these limits, particularly in groups S1 (plants with a capacity less than 300 MW) and S4 (plants with a capacity higher than 300 MW). It was also found that the frequency of exceeding the annual effective dose limits (IAEDs) showed an increasing trend with the increasing installed capacity of the facility. These findings underscore the importance of plant capacity as a key factor to consider in the radiological risk assessment associated with coal fly ash. This study’s outcomes are crucial for informing environmental risk management strategies, guiding safe waste processing practices, and shaping environmental policies within the energy sector in Central and Eastern European countries, including Poland. Full article

Mass timber construction is gaining popularity in mid-rise and tall buildings due to its sustainability, aesthetics, versatile prefabrication, light weight, and faster construction time compared to conventional building materials such as concrete and steel. One of the challenges with timber construction is a potential fire hazard, and the risk is even aggravated in taller buildings due to the increased evacuation period. Several researchers have identified and reported important parameters that will have direct influence over mass timber fire performance behaviour. However, the current findings from the literature do not provide a correlation between the key parameters and the fire performance behaviour. This paper presents a review of experimental fire testing of mass timber structures and analyses the fire performance results output obtained from the experimental testing. This paper attempts to identify several key parameters that influence the fire performance behaviour of mass timber structures, such as peak temperature, charring rate and decay behaviour. The correlation between the key parameters and the fire performance behaviour of mass timber structures will enhance in developing a rational model to determine the time to reach the fire growth, peak temperature, charring behaviour, structural integrity (strength and stiffness reduction) and decay behaviour of the exposed timber. Full article

Post-earthquake fires are typically of great concern for fire protection services, which are expected to be in high demand immediately after a strong earthquake. The post-earthquake functionality of fire stations is necessary after strong earthquakes to reduce potential fire damage and improve emergency services. A reliable assessment of the seismic vulnerability and expected damage for fire stations is therefore a necessary step towards the identification of the most vulnerable structures and the prioritization of seismic retrofit activities. This article presents the development of a methodology for the damage assessment of fire stations based on earthquakes scenarios. The framework is based on four models: seismic hazard, inventory, fragility and impact. The seismic hazard model represents ground shaking in terms of intensity measure at each station using a ground motion prediction equation for Eastern Canada. The inventory model categorizes all the fire stations in building classes based on construction material and seismic code level. The fragility model associates building classes with fragility functions that provide the relationship between intensity measure and expected damage probabilities. The impact model converts damage probabilities into a mean damage state. All Montreal fire stations were selected as case study demonstrations. Simulations were conducted by varying the epicenter location and magnitude for a total number of 345 scenarios. Simplified relationships that correlate the earthquake magnitude and expected damage were developed. The study showed that, for magnitude 6 earthquakes, 45% of stations on average would sustain at least moderate damage. The methodology is particularly useful for emergency planning and prioritization of seismic retrofit activities. Full article

Air-supported membrane structures (ASMS) are widely applied in warehouses and large-span venues due to their lightweight and cost-effective nature. However, as a storage building with a lot of combustible material and significant fire hazards, it imposes stringent demands on structural stability and safety. This paper investigates the impact of fire-induced effects on stability using Fire Dynamics Simulator (FDS) software, with a case study focusing on an ASMS coal storage bin. The study comprises two key components: (1) internal pressure stability and (2) thermal stability. Results show that ambient temperature, leakage area and air supply govern non-fire pressure stability, with a 10 K increase reducing pressure by 9.4 Pa. During fires, HRR, location and growth type effect the stability of ASMS buildings. Thermal stability analysis reveals 6 m horizontal spacing can prevent coal ignition (<12.5 kW/m², <100 °C), while 10 m vertical spacing can avoid PVC membrane pyrolysis. These findings provide critical design guidelines for ASMS fire protection, highlighting the necessity of asymmetric safety margins due to vertical–horizontal radiation anisotropy. Full article

The management of asbestos-containing waste (ACW) presents a significant environmental challenge due to the material’s widespread historical use and persistent toxicity. While landfilling remains the primary disposal method, it poses long-term environmental risks and conflicts with circular economy principles. Across Europe, large quantities of asbestos remain in building stock, including approximately 15 million tons in Poland, 4.5 million tons in Lithuania, and 1 million tons in Latvia. This study examines Latvia’s ACW management challenges and opportunities, combining theoretical analysis with empirical research. A large-scale survey (n = 2005) revealed significant gaps in public knowledge, with 28% of respondents willing to reuse asbestos-containing roofing despite recognizing its hazards, highlighting a critical disconnect between awareness and behavior. The study also assessed Latvia’s pilot Asbestos Removal Program, demonstrating high public demand but limited funding capacity. Thermal treatment, particularly plasma vitrification, was identified as the most mature alternative to landfilling, though implementation barriers include high capital costs and specialized expertise requirements. Findings emphasize the need for sustainable financing mechanisms, such as a differentiated landfill tax, to ensure the long-term viability of asbestos removal initiatives. Latvia’s experience provides valuable insights for other nations seeking to mitigate ACW-related health and environmental risks through improved policy frameworks and practical management solutions. Full article

Management of occupational health and safety (OHS) plays a critical role in building safe and effective working environments, especially in industries defined by dangerous operations like manufacturing. Secondary industries are characterized by their use of dangerous materials, complex machinery, and repetitive manual work, prompting the need for stringent OHS laws to protect employees and support business sustainability. Although extensive regulatory materials like ISO 45001 and EU Directive 89/391/EEC exist, the implementation of OHS standards varies among organizations significantly. While larger organizations adopt structured frameworks of safety management, small and medium enterprises (SMEs) are often confronted by economic and technical constraints. As a result, policies only appear on paper, and their attitude toward occupational safety is passive. Employing a structured survey analysis, this study evaluates the level at which manufacturing companies in Macedonia-Thrace, a region in Northern Greece, implement OHS actions, the barriers that face them, and how OHS programs influence business performance. Based on the findings, companies that apply proactive OHS practices achieve more productivity, increased staff retention, and lower costs due to accidents, while SMEs often find it difficult to undertake comprehensive policies. The research further identifies the impact of electronic technology, regulation, and leadership on enhancing OHS performance. This study provides evidence-based recommendations on policy changes through the exploration of regionalized patterns of adoption of OHS practices by industrial companies and key policy intervention areas. By eliminating underlying structural loopholes in the implementation of OHS, this paper provides research-backed policy solutions aimed at enhancing work safety and improving corporate performance in the secondary industry. The reinforcement of OHS measures not only reduces hazards at the workplace but also improves the resilience of business, its competitiveness, and conformity to regulations. Full article

This article discusses the current problem of industrial waste disposal and its use in the production of building materials, which corresponds to the global concept of sustainable development. Attention is mainly paid to the development of a gruntosilicate composite (concrete) based on a mineral slag binder using drilling sludge from the mining industry, ashes from thermal power plants and electrothermophosphoric slag. Physico-chemical studies of man-made raw materials have been carried out, including analysis of chemical and mineralogical composition, granulometric characteristics, radiation safety and other parameters. It has been established that drilling mud, thermal power plant ash and electrothermophosphoric slag meet the requirements for use in building materials and belong to non-hazardous waste. The optimal ratios of the components in the composition of gruntosilicate concrete have been experimentally determined. The highest compressive strength (3.0–3.5 MPa) is achieved with a drilling mud content of 15–23% and a mineral slag binder of 10–20%. It is shown that the introduction of these wastes improves the structure of the material, reduces shrinkage deformations and ensures compliance with the requirements of road surfaces of the II–III classes. The use of industrial waste in construction will reduce the cost of raw materials by approximately 10–30%, reduce the environmental burden and solve the problem of waste disposal. The results of the study demonstrate the prospects of creating a waste-processing industry capable of processing up to 40% of industrial waste into building materials. Full article