Search Results (160)

The movement towards low-emission and sustainable building practices has driven increased use of natural, carbon-based materials such as wood. While these materials offer significant environmental advantages, their inherent flammability introduces new challenges for timber building safety. Despite advancements in fire protection standards and building regulations, the risk of fire incidents—whether from technical failure, human error, or intentional acts—remains. The rapid detection of fire onset is crucial for safeguarding human life, animal welfare, and valuable assets. This study investigates the potential of monitoring fire precursor gases emitted inside building structures during pre-ignition and early combustion stages. The research also examines the sensitivity and effectiveness of commercial smoke detectors compared with custom sensor arrays in detecting these emissions. A representative structural sample was constructed and subjected to a controlled fire scenario in a laboratory setting, providing insights into the integration of gas sensing technologies for enhanced fire resilience in sustainable building systems. Full article

The increasing complexity of urban structures has significantly elevated the risk and severity of façade fires in high-rise buildings. Unlike traditional models assuming continuous fuel beds, real-world fire scenarios often involve discrete combustible materials arranged in discrete fuel matrices. This study presents a systematic investigation into the influence of lateral spacing on vertical flame propagation behavior. Laboratory-scale experiments were conducted using vertically oriented polymethyl methacrylate (PMMA) fuel arrays under nine different spacing configurations. Results reveal that lateral spacing plays a critical role in determining flame spread paths and intensities. Specifically, with a vertical spacing fixed at 8 cm, a lateral spacing of 10 mm resulted in rapid flame growth, reaching a peak flame height of approximately 96.5 cm within 450 s after ignition. In contrast, increasing the lateral spacing to 15 mm significantly slowed flame development, achieving a peak flame height of just under 90 cm at approximately 600 s. This notable transition in flame dynamics is closely associated with the critical thermal boundary layer thickness (~11.5 mm). Additionally, at 10 mm spacing, a chimney-like effect was observed, enhancing upward air entrainment and resulting in intensified combustion. These findings reveal the coupled influence of geometric configuration and heat transfer mechanisms on façade flame propagation. The insights gained provide guidance for cladding system design, suggesting that increasing lateral separation between combustible elements may be an effective strategy to limit flame spread and enhance fire safety performance in buildings. Full article

Mining waste from both underground and open-pit mines is typically placed in surface sites known as mine waste dumps. Over time, as large volumes of mining waste accumulate, these dumps become higher due to the limited surface area allocated to dumping. Ensuring the stability of mine waste dumps is a major concern for both mining operations and local governments due to safety risks to the dumps themselves and their surrounding environments. In some cases of mine waste dump, spontaneous combustion poses a significant challenge, affecting not only the environment but also the slope stability of mine waste dumps. This review synthesizes existing research on the mechanisms of spontaneous combustion, its thermal effects, and the implications for geomechanical stability in mine waste dumps. It also examines methods for monitoring and controlling these processes, identifies gaps in the current research, and suggests directions for future studies. The review also reveals that combustion-induced temperature changes, material degradation, and gas generation significantly impact the geotechnical properties of building material dumps, contributing to slope failure. This review is expected to provide valuable insights that help mining authorities assess risks, minimize impacts, and implement preventive measures to mitigate unexpected spontaneous combustion-induced slope failures in mine waste dumps. Full article

Aluminium composite panels (ACPs) have been used in almost every high-rise building because of their aesthetic and thermal properties. However, due to the nature of the combustibility of polymeric core materials, the fire issue is the main concern throughout the world. Several fire occurrences have been noticed in different countries. The ignition of combustible core materials used in ACP cladding is mainly responsible for spreading fire. Building-safety regulatory authorities have enforced new obligations to ban combustible ACP panels in high-rise buildings, especially in Australia and the UK. This is now considered as one of the critical components in these buildings. This study aims to comprehensively overview different types of cladding panels, core filler materials, flame-retardant mechanisms, their preparation methods, and recent developments. The PRISMA method has been used to conduct a systematic literature review. From the Scopus and Google scholar databases, a total of 180 documents have been selected using two relevant keywords through the screening process. This study reviews existing studies, covering cladding panel classifications based on standard codes, and existing ACP panels’ flammability, thermal, and mechanical properties. Following an in-depth recent literature review, the study outlines the combustibility and energy efficiency challenges and offers recommendations for future research to develop non-combustible cladding panels. 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

Cellulose-based aerogel is an environmentally friendly multifunctional material that is renewable, biodegradable, and easily surface-modified. However, due to its flammability, cellulose serves as an ignition source in fire incidents, leading to the combustion of building materials and resulting in significant economic losses and safety risks. Consequently, it is essential to develop cellulose-based building materials with flame-retardant properties. Initially, a porous cellulose-based flame-retardant aerogel was successfully synthesized through freeze-drying, utilizing lignocellulose as the raw material. Subsequently, phosphorylation of cellulose was coupled with Ca²⁺ cross-linking via self-assembly and surface deposition effects to enhance its flame-retardant properties. Finally, the synthesized materials were characterized using infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, mechanical compression testing, and scanning electron microscopy. The aerogel of the phosphorylated cellulose nanofibrils cross-linked via 1.5% CaCl₂ exhibited the most effective flame-retardant properties and the best mechanical characteristics, achieving a UL-94 test rating of V-0 and a maximum flame-retardant rate of 90.6%. Additionally, its compressive strength and elastic modulus were recorded at 0.39 and 0.98 MPa, respectively. The preparation process is environmentally friendly, yielding products that demonstrate significant flame-retardant effects and are non-toxic. This product is anticipated to replace polymer-based commercial aerogel materials, representing a sustainable solution to the issue of “white pollution”. Full article

As a crucial provider of building materials, the cement industry occupies a central position in developing Hebei Province’s construction sector while presenting considerable challenges to achieving regional carbon neutrality targets. This paper establishes a carbon emission accounting model for cement production, quantifies the carbon emission trajectory of Hebei’s cement industry from 2005 to 2023, applies the STIRPAT (Stochastic Impacts by Regression on Population, Affluence, and Technology) model to analyze the influencing factors of carbon emissions, and predicts future emissions from 2024 to 2035 using scenario analysis methods. The results indicate that the overall carbon emissions from the cement industry in Hebei Province exhibited fluctuating trends between 2005 and 2023, primarily driven by carbonate decomposition and fossil fuel combustion during the clinker calcination stage. Population size, GDP per capita, urbanization rate, industrial structure, energy consumption structure, cement consumption structure, and cement production were identified as positive contributors to carbon emissions. In contrast, energy intensity was found to have a mitigating effect. The prediction results show that the industry reached its carbon emissions peak at 70.29 million tCO₂e in 2020. Under the enhanced low-carbon scenario, emissions are expected to decline by 20.9% relative to the baseline scenario, reaching 34.95 million tCO₂e by 2035. Deep emission reductions should be achieved through technological upgrading and policy guidance to support the low-carbon transformation of Hebei’s cement industry and promote sustainable urbanization. Full article

Biochar can be regarded as a high-energy type of solid fuel produced via pyrolysis, which is the thermal modification of biomass of plant or animal origins. The biggest advantage of biomass relative to classic fossil fuels is the significant reduction in carbon dioxide emissions in the combustion process. Biochar is also considered a natural soil additive for improving soil parameters, increasing crop yields, remediating pollutants, and reducing emissions of methane, among other things. Over the past few years, the range of biochar applications has expanded significantly, as reflected in the number of scientific articles on the topic. Pyrolysates are used in the production of cosmetics, pharmaceuticals, building materials, animal feed, sorbents, and water filters, as well as in the field of modern energy storage and conversion, such as supercapacitors. The key importance of this material is attributed to its ability to sequestrate carbon and reduce greenhouse gas emissions. The relentless growth of the global economy and the high demand for energy generate large amounts of CO₂ in the atmosphere. Solving the carbon balance problem and the low-carbon energy transition toward carbon neutrality is very challenging. Biochar therefore appears to be an excellent tool for creating systems that can play an important role in mitigating climate change. The purpose of this review is to consolidate the existing knowledge and assess the potential of biochar in carbon neutrality based on the application sector. 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

Bamboo is a fast-growing biomass material with excellent performance, making it a preferred choice for the development of green and low-carbon building materials. However, challenges such as combustibility and difficulties in processing and utilization persist. In this study, bamboo chips are wrapped in fiberglass cloth and cemented with magnesium oxychloride cement (MOC) to develop green, environmentally friendly, flame-retardant, and carbon-storing bamboo-based composite panels. Firstly, the optimal ratio of the inorganic adhesive MOC was systematically investigated, and flue gas desulfurization gypsum (FG) was added to enhance its water resistance. The flexural strengths of the composite board in the direction of the bamboo fiber and that perpendicular to it were found to be 15.71 MPa and 34.64 MPa, respectively. Secondly, numerical simulations were conducted alongside plate experiments, analyzing the floor and wall made from the boards. The results indicate that since the fiber-reinforced bamboo board as a lightweight wall can meet the requirements for a two-story building, it does not satisfy safety standards as a floor slab due to the higher loads. Despite this limitation, the fiber-reinforced bamboo board shows promising application prospects as a green and low-carbon alternative. Full article

Fire is a combustion reaction where fuel reacts with oxygen in the presence of heat, releasing energy as light, heat, and flames. The main components of fire are fuel, oxygen, and heat. All three components must be present to cause a fire. Fire is a significant threat to residential and commercial buildings, often intensified by high fuel content in building materials such as wood and synthetics. This paper summarizes fire types and damages, loss of property and life, fuel content in building materials, and a method to reduce fire risk by minimizing the building material’s fuel content. This method uses minerals (coal combustion residual (CCR)), primarily inorganic oxides bonded with a small percentage of polyurethane binder, to manufacture a composite material moldable into multiple building products. The composite was tested as per the ASTM for mechanical, thermal, and fire safety performance. ASTM D635-based fire testing showed self-extinguishing behavior with significantly reduced burn rate and lengths (1–2 mm). A low calorific value of 6.6 MJ/kg was determined separately. The test results demonstrate that CCR-based mineral composites offer a fire-resistant, structurally sound, and eco-friendly alternative to wood products. This research supports recycling inorganic minerals into fire-resistant building products that enhance safety. Full article

Polyurethane foam (PF) is a versatile polymer widely used in various applications. By changing the composition of polyol and isocyanate, these foams can be classified into rigid polyurethane foams (PUFRs) and flexible polyurethane foams (PUFFs). The flexible polyurethane foam (PUFFs) is well known for its sound absorption capacities; nevertheless, its flammability poses significant safety hazards. The purpose of this study is to look into how flexible polyurethane foam reacts to fire, specifically its combustion properties, and the risks that come with them. The study aims to find out the rates of horizontal and vertical burning, the make-up of the reaction products, and the temperatures that build up inside the polyurethane foam mass when a support pole is placed in front of the stage and sound-absorbing material is added to stop stage sounds from reverberating. There were performed experiments to determine the fire behavior of the samples in contact with an ignition source in the form of a small flame and experiments to determine the ignition temperature of the sound-absorbing sponge, where it was found that vertical position accelerates combustion, and in practical applications, this aspect must be considered for fire prevention. To determine the combustion gases, several methods were used, namely spectrophotometric, ion chromatography, and gas-chromatographic methods. Analysis of the gases resulting from the combustion of the sound-absorbing sponge indicates the presence of dangerous toxic compounds (hydrogen cyanide, carbon monoxide, and hydrochloric acid), which can endanger human health in the event of a fire. Full article

Timber heritage buildings reflect the character and specifics of the region in which they are located and in which they were built. They form part of memory and history, preserving the traditions and culture of a community. The fact that their building material is timber makes them more susceptible to fire. The purpose of the article is to evaluate the current state of fire protection of timber heritage buildings. Having established this status, we will analyze the results and list the main problems we have identified. We will propose measures to reduce the risk of fire occurrence and spread. For the purposes of our research, we followed the developed methodologies for fire protection assessment of heritage buildings. We developed a checklist which we used for data collection. We analyzed the results, and then used synthesis to look for areas of correlation between the different buildings. The most common shortcomings in the fire protection of sacral timber buildings are the absence of fire protection coatings, missing or non-functioning electric fire alarms, and the absence of a stable fire extinguishing system. The presence of combustible materials in the building or its immediate vicinity, water sources, access roads or the travel time of the fire brigade to the building were also problematic. The main challenge to increasing fire protection of heritage timber buildings in Slovakia is the lack of funding. Without funds, it will not be possible to equip the buildings with fire-fighting equipment and the sustainability of these objects for future generations will not be possible. Full article

Hydroxyl-terminated polyether (HTPE) propellants are attractive in the weapons materials and equipment industry for their insensitive properties. Storage, combustion, and explosion of solid propellants are affected by their mechanical properties, so accurate mechanical modeling is vital. In this study, deep neural networks are applied to model composite solid-propellant mechanical behavior for the first time. A data-driven framework incorporating a novel training–testing splitting strategy is proposed. By building Neural Networks (FFNNs), Kolmogorov–Arnold Networks (KANs) and Long Short-Term Memory (LSTM) networks and optimizing the model framework and parameters using a Bayesian optimization algorithm, the results show that the LSTM model predicts the stress–strain curve of HTPE propellant with an RMSE of 0.053 MPa, which is 62.7% and 48.5% higher than the FFNNs and the KANs, respectively. The R² values of the LSTM model for the testing set exceed 0.99, which can effectively capture the effects of tensile rate and temperature changes on tensile strength, and accurately predict the yield point and the slope change of the stress–strain curve. Using the interpretable Shapley Additive Explanations (SHAP) method, fine-grained ammonium perchlorate (AP) can increase its tensile strength, and plasticizers can increase their elongation at break; this method provides an effective approach for HTPE propellant formulation. Full article

Fly ash, a primary solid waste product of coal combustion, poses severe threats to human health and the environment due to its massive accumulation. Leveraging the modified porous structure and engineered adsorptive properties of fly ash, its integration with nano-photocatalytic materials can achieve dispersion and stabilization of the photocatalyst, significantly enhancing photocatalytic activity while enabling a synergistic effect between adsorption and photocatalysis. This paper focuses on the issue of agglomeration in semiconductor photocatalytic materials and briefly reviews the preparation methods and applications of modified fly ash-supported photocatalytic materials from both domestic and international perspectives in recent years. Initially, the properties and modification techniques of fly ash are analyzed, with a special emphasis on three methods for preparing fly ash-based photocatalytic composites: the sol-gel method, hydrothermal synthesis, and liquid-phase precipitation. A comparative analysis of the advantages and disadvantages of these three methods is conducted. Furthermore, the performance of the materials and the positive impacts of fly ash-composite photocatalysts are analyzed in terms of applications such as the degradation of pollutants in water, the degradation of NOx and VOCs gaseous pollutants, self-cleaning properties, and CO₂ reduction capabilities. These analyses indicate that fly ash primarily serves as an adsorbent and carrier in these applications. However, as a carrier, fly ash possesses a limited number of active sites, and its modification technology is not yet fully mature. Additionally, research in this area is still in the experimental stage and has not transitioned to engineered production. Therefore, there is a need for continuous improvement in fly ash modification techniques. Furthermore, additional research should be conducted on functional building materials loaded with fly ash-supported photocatalytic materials to enhance their practicality. Full article