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AbstractIn order to reach the fire protection standard for new energy vehicle battery packs, the incorporation of SiO2 aerogel particles as a functional filler in the nitrogen and phosphorus fire-retardant system is necessary due to the inadequate mechanical properties. The effects of SiO2 aerogel on the properties of the coatings for the electric car battery pack were investigated by fire protection test, thermogravimetric analysis, limited oxygen index, UL-94 vertical test, combustion test, mechanical properties test, and weathering resistance test. The backside temperature fireproof coatings containing 1.5% SiO2 aerogel was effectively reduced to 250.2 ± 0.1 °C and the residual weight of the coating reached 32.61 ± 0.01%. The composition and structure of the carbon layer were analyzed further. Especially, the weight loss percentage of the fireproof coating is only 5.87 ± 0.02% in the water resistance test. However, excessive SiO2 aerogel decreased the performances of fireproof coatings. [ABSTRACT FROM AUTHOR]

Original timber stairwell doors in historic masonry apartment buildings of architectural heritage value can be found in the larger cities of Norway. In Oslo, there are around 4000 such buildings, of which many still hold preserved original stairwell doors. The doors often have glass with decorative patterns in the upper parts, and timber panels on the lower part. Old residential buildings are vulnerable to fire due to the building construction and need fire protection upgrades. The stairwell doors are critical elements to prevent fire spread and to keep evacuation routes safe, so their function and condition are important to the level of fire protection in the building. The research work in this paper aims to find retrofit methods for upgrading the fire resistance of these types of doors so they maintain their integrity and insulating properties for up to 30 minutes, at the same time as they maintain their architectural expression. The upgrades must be as little intrusive and destructive as possible. Intermediate scale tests were carried out in a fire resistance test furnace, using different door configurations. The tests lasted between 30 minutes and 42 minutes, with a thermal exposure from the standard time/temperature curve described in EN 1363–1. The results from the tests showed that 40 mm thick laminated wood could withstand up to 30 minutes of fire exposure, thin timber panels could be upgraded using stone wool and robust gypsum boards type R, and that fire-resistant glass could be mounted on the inside of the original glass in different ways. Visual observations indicate that adding smoke seals inside the door leaf are effective for stopping cold and hot smoke. The solutions presented enables the preservation of the original doors' architectural design, their historical values and aesthetic character. [ABSTRACT FROM AUTHOR]

Timber–concrete composite (TCC) structure system is most frequently used in large-span structures. Recently, a performance-based fire safety design method named improved travelling fires methodology (iTFM), which is suitable for long-span structures, has been developed. In this article, an energy-based time equivalent method (EBTEM) is proposed, while its effectiveness is experimentally verified. The proposed method can be used to evaluate the fire resistance of the TCC structures subjected to iTFM fires. The results indicated that the damage degree at different spatial positions of the TCC structure under the same fire size was different, and the location with the least and most serious damages occurs towards the beginning and middle of the fire path, respectively. The results show that this difference in damage degree mainly depends on the fire size, and the difference becomes less pronounced as the fire size increases. Concomitantly, it can be obtained that the damage degree under the different fire sizes was different, and the smaller the fire size, the greater the damage degree. Hence, when the EBTEM is adopted to design the TCC structures exposed to iTFM fires, the setting of fire protection target is largely determined by the actual fire size. [ABSTRACT FROM AUTHOR]

Because fire safety cannot be measured directly, building regulation uses test ratings to determine whether materials and products meet societal expectations. Fire resistance constitutes the most enduring means of gauging fire safety, providing ratings for how elements of structure perform in a standard furnace test. Although it has long been known that this test is unrepresentative of real building fires, fire resistance testing remains central to building regulation because it has proved useful. This utility stems not just from the perceived value of the test metric as a proxy for building fire safety, but also from its role as a boundary object that facilitates regulation amongst diverse practitioners. Although fire science has developed greatly since the fire resistance test standard was defined, fire scientists are no longer a relevant social group; closure around the test standard is now widely embedded in regulations and industry practice. Advances in fire science offer the prospect of first principles fire safety engineering that can enable bespoke building solutions that are more optimised than those embedded in the conservative one-size-fits-all regulations based on fire resistance, but adherence to the fire resistance approach means most practitioners lack sufficient knowledge to make safe use of new design methods. Testing orientated to fundamental understanding has been neglected, presenting an obstacle to the innovative solutions required for the built environment in the twenty-first century. [ABSTRACT FROM AUTHOR]

In some countries, airguns capable of inflicting injuries are legally regulated and considered to be controlled firearms. In this study, the deformation of witness plates was utilized to assess the wounding potential of airguns. A series of firing tests was conducted using four airguns and two lead ball-type projectiles. The impact velocity (V) and energy density (ED) of the projectiles fired at the witness plates were determined based on a ballistic chronograph. The deformation depths (H) of the uncracked and unperforated witness-plates were measured. Correlation analysis revealed that H was linearly correlated with V. The coefficient of determination between H and V was greater than 0.99. Two-variable linear equations were employed to calculate the evaluated impact velocity (VE) and energy density (EDE). Validation firing tests were conducted using four real-case airguns seized and submitted by local police departments. To calculate VE and EDE, we employed H and linear equations, respectively. The percentage difference between ED and EDE was less than or equal to 12%. These results demonstrate that the witness-plate deformation method is an efficient presumptive test for reducing backlogs of muzzle energy examinations of airguns in forensic laboratories. [ABSTRACT FROM AUTHOR]

Conventional evaluation of the overall mechanical properties and ultimate flexural capacity of prestressed hollow core slabs after a fire exposure depends heavily on the inversion of fire scene temperature. To avoid this drawback, this paper presents a new methodology which combines a generalized regression neural network (GRNN) with conventional non-destructive testing technology. Thereby, a neural network model for predicting the material performance parameters after fire exposure is obtained based on conventional testing indices. A hollow core slab bridge is used as an example, and the applicability of the trained network model is confirmed using numerical simulation and a field failure test. Results show that the overall relative error of GRNN in predicting the key performance parameters of the bridge after fire exposure is less than 10%. Further, because of the good thermal inertia of the concrete, the relative error in predicting the material performance parameters of steel after a fire is less than 5%. Moreover, the ultimate flexural capacity of the prestressed hollow core slab after a fire can be accurately evaluated by feeding the material performance parameters predicted by GRNN neural network into the finite element (FE) model. [ABSTRACT FROM AUTHOR]

Cable supported bridges are typically part of community-critical infrastructure and therefore the consequences arising from extensive structural damage due to a fire and the subsequent operational discontinuity could be significant beyond the damage to the bridge itself and the cost of repairs. Bridge design standards generally do not provide guidance and hence fire resistance requirements are often informed by first principles assessments of the thermal and structural response of the structure to proposed fire scenarios. A deterministic assessment can provide a reasonable worst-case scenario but it does not allow bridge stakeholders to make informed decisions with regards to uncertainty and the low likelihood of fires occurring to identify the benefits of investments in structural fire protection. This is because the target reliability required for each bridge may be different depending on its characteristics, and the expected fire severity has a probabilistic nature. This research aims to fill this gap by undertaking a reliability-based analysis to assess the probability of structural failure by considering the probability of a fire of a given size occurring and the uncertainty in the incident location and wind. The methodology is demonstrated through the case study of an operational 450 m long cable supported bridge section and a fire scenario based on a liquid fuel tanker. Liquid tankers can result into two type of fire scenario: first, a fire being contained within the tanker; and secondly, a fire due to a pool on the deck. Both fire scenarios have been characterised and it was determined that the contained tanker scenario presents a more onerous design case owing to its more prolonged duration. A Monte Carlo analysis was undertaken for a total of 10,000 independent trials of the combination of the location of the fire and the wind direction. The frequency of the fire was also examined to establish the probability of structural failure of a cable. It was established that the inclusion of wind can sometimes reduce the estimated height at which cables may experience temperatures with the potential to cause cable failure. However, for a number of the cases, the estimated height can remain broadly similar (i.e. within a couple metres difference) to the worst-case calculated value. Based on this analysis, the influence of the required level of reliability as well the fire protection duration specification agreed with bridge stakeholders can be used to determine the height at which cable fire protection is necessary to reduce the probability of structural failure to a level acceptable to the stakeholders. This approach allows bridge designers and stakeholders to make informed decisions with regards to provision and extent of fire preventive/protective measures for cable supported bridges. [ABSTRACT FROM AUTHOR]

This paper discloses an early performed study on the fire-resistance design framework for cable-stayed bridges, including (1) the identification of potential fire scenarios and the calculation of fire return periods, (2) computational fluid dynamics simulation of the fire environment and analytical models of flame dimensions, (3) coupling thermomechanical finite element simulation to capture the bridge response, and (4) the determination of fire prevention and protection measures. The framework was then utilized on a two-level steel cable-stayed bridge. The return periods of vehicle fires on the upper, lower, and two-level decks were 1.13, 1.88, and 0.71 years, respectively. Numerical results showed that the bridge could resist car, bus, and truck fires but not tanker fires. Regulative fire prevention measures were undertaken to suppress the fire risk on the bridge, and drainages were designed to exclude the accumulation of fuel leaks. Although the work was finished in 2007, the proposed framework can still be a prototype for designing cable-stayed bridges against fires nowadays. From the current view, the framework can be improved by incorporating traffic data to calculate the fire return periods, using more precise fire models developed for bridges, and quantifying the cost-benefit of employing fire prevention and protection measures. [ABSTRACT FROM AUTHOR]

Analysis of turbulence-induced scintillation on a round-trip propagation path was performed. A simplified equation for the cross-covariance of intensity fluctuations on a round-trip path was derived. This equation was validated both experimentally over a 1 km horizontal path and using a wave-optics simulation. An analytical solution was obtained for a non-linear integral equation relating the crosswind velocity profile to a spatial–temporal cross-covariance of intensity fluctuations observed in the laser return. A method for crosswind profile reconstruction using an optical sensor with varying beam divergence was developed and experimentally demonstrated. A portable, battery-powered optical wind sensor with fixed beam divergence suitable for mounting on a riflescope was constructed and field-demonstrated in live fire tests. Results of the live fire tests validated the proposed method. [ABSTRACT FROM AUTHOR]

Although much attention focuses on mental health recovery and stigma, less attention is paid to substance use especially in rural areas. This qualitative study draws on Foucauldian and intersectional approaches to examine the sociocultural processes by which stigmatized identities are constructed and rejected at micro and macro levels. A thematic analysis is applied to 40 interviews with people with substance use issues in two rural communities. Findings illustrate that stigma is constructed through binary identity categories and intersectional identities rooted in neoliberal contexts. Resistance is demonstrated at personal, peer, public, and structural levels, offering counter narratives of strength and resilience. [ABSTRACT FROM AUTHOR]

This paper investigates the influence of the reduced pressure on the temperature profile of the weak and strong fire plumes by elevating n-Heptane fires. A series of elevated n-Heptane fire tests were conducted in a full-scale simulated Boeing 737–700 aircraft cargo compartment at 70 kPa, 80 kPa, 90 kPa and 100 kPa. The experimental results show that both the centerline temperature rise and the maximum ceiling temperature rise of weak and strong plumes at reduced pressures can be represented in three-region law similar to McCaffrey plume model. Thereinto, the weak plume temperature increases with the decrease of the atmosphere pressure owing to the low air entrainment, while the strong plume temperature in the continuous flame region decreases at reduced pressure, because the hot thermal flow of the strong plume impinges the ceiling violently causing the more air entrainment. The maximum ceiling temperature at the reduced pressure changes as similar with the centerline temperature driven by strong plumes. By introducing the reduced pressure coefficients, new correlations for predicting the centerline temperature and maximum ceiling temperature induced by weak and strong plumes are proposed with wider application range. [ABSTRACT FROM AUTHOR]

Examining the progression of fire in wood and wood-based materials on a laboratory scale is a challenging endeavour owing to practical constraints inherent to real fire scenarios. Factors such as the rate of fire spread, its intensity, duration, and the extent of its impact on timber structures are notably influenced by the quantity of timber surfaces exposed within a given building. Non-structural timber surfaces encompass decorative or flat linings on walls, ceilings, and flooring. The objective of this research was to devise a methodology that combines X-ray computed tomography (CT) scanning with concurrent fire testing of wood, enabling the assessment of the fire's course and its deleterious effects on timber materials. The overarching goal of this novel tool is to expand our understanding of the fire behaviour exhibited by emerging and modified wood materials. To achieve this, a specialized fire chamber was integrated with an X-ray CT scanner to enable simultaneous fire testing and scanning procedures. In this study, one transversal and one cross-sectional surface of Norway spruce wood were subjected to fire, and the progression of the fire was scrutinized using CT scanning. As the density of the combusting wood material substantially decreased due to carbonization induced by pyrolysis, the advancement of the carbonized front was thoroughly investigated throughout the entire material volume. Ultimately, the findings indicate that CT scanning holds promise as a valuable tool for investigating the behaviour of solid wood, wood-based products, or other lignocellulosic materials when subjected to fire conditions. [ABSTRACT FROM AUTHOR]

Electrical cables must fulfil the Construction Product Regulation (CPR) by testing them according to EN 50,399. Nevertheless, an unfordable trial and error procedure could stem from the definition of new cables. To achieve a better understanding of fire behavior of cables, researchers have been using techniques such as bench and reduced scale tests and computational fire models result in a way to minimize trial and error process. The present work proposes the combination of bench scale tests, using cone calorimeters and fire simulation modeling. In a first step, the thermal characterization of the cable parts is carried out, and then, in a second step, use these data to model complete cable samples in cone calorimeter tests. The simulations are compared with experimental data of two already rated cables. This process is intended to discard erroneous configurations, which display in bench scale signs of misbehavior compared with rated cables. This would avoid the manufacture of the complete cable if the results do not fulfill the requirements, and eventually, proceed to its production and test in full-scale when they do. This work has been carried out with two multi-core cables and the materials they were made of, and the results showed: a) the inverse modeling process to characterize materials parts obtained a fairly accurate approach, with small inaccuracies in the peaks of the curves; b) two simulation models (simple and detailed) were able to reproduce in general terms the heat release rate curve; however, they released more energy than experimental tests and some discrepancies in the peaks were observed. Despite its simplicity, simple model obtained results fairly close to the experimental curves and took less time to simulate. [ABSTRACT FROM AUTHOR]

This study extends the authors' previous numerical and experimental studies simulating the progressive collapse of steel stiffened-plate structures in fire events (Paik JK, Ryu MG, He KH, Lee DH, Lee SY, Park DK, Thomas G. 2021a. Full-scale fire testing to collapse of steel stiffened plate structures under lateral patch loading (part 1) – without passive fire protection. Ships Offsh Struct. 16(3):227–242; Paik JK, Ryu MG, He KH, Lee DH, Lee SY, Park DK, Thomas G. 2021b. Full-scale fire testing to collapse of steel stiffened plate structures under lateral patch loading (part 2) – with passive fire protection. Ships Offsh Struct. 16(3):243–254; Ryu MG, He KH, Lee DH, Park SI, Thomas G, Paik JK. 2021. Finite element modeling for the progressive collapse analysis of steel stiffened-plate structures in fires. Thin-Walled Struct. 159:107262). Specifically, this study demonstrates that the computational models developed in the earlier studies can be applied to the analysis of the heat transfer and fire-induced progressive collapse behaviour of the topside structures of a ship-shaped offshore installation. To this end, a hypothetical VLCC-class floating, production, storage and offloading (FPSO) unit hull structure is considered, and transient thermal elastic-plastic large-deformation finite element models are used. The novelty of this study and its contribution to industry are the development of a practical procedure to ensure the fire safety of large-scale steel-plated structures with complex geometries. [ABSTRACT FROM AUTHOR]

The International Convention for the Safety of Life at Sea (SOLAS) recognises five different fire-extinguishing system solutions for ro-ro spaces on ships; manually activated water spray systems (Resolution A.123(V)), automatic sprinkler or deluge water spray systems and automatic nozzle or deluge water mist systems (MSC.1/Circ.1430), high-expansion foam systems and gas fire-extinguishing systems (FSS Code). A review of potential commercially available alternative systems, their expected performance efficiency and water consumption was made. Based on this review, two alternative fire-extinguishing systems were identified: Compressed Air Foam Systems (CAFS) and foam-water sprinkler/spray systems. Fire suppression performance testing of water spray systems according to the Resolution A.123(V) and MSC.1/Circ.1430, a CAFS and a foam-water spray system were conducted. The water spray system per MSC.1/Circ.1430 had superior performance while the system per Resolution A.123(V) and the foam-water spray system limited the fire size to some degrees. The CAFS provided limited fire suppression performance. [ABSTRACT FROM AUTHOR]

In the current paper, the thermal insulation material from the wool of sheep grown in Lithuania is analyzed. Three types of thermal insulation material were produced: horizontal orientations, corrugated from the individual layer obtained, and corrugated from individual mats. The 50 mm thick products were prepared and their main performance characteristics were evaluated: thickness changes, thermal conductivity, tensile strength, short-term water absorption, and flammability. Changes in the thickness of the materials were determined under different loads, and dependences on the density of the material were obtained. Thermal conductivity was measured for products of different densities, evaluated separately for horizontal orientation and corrugated products, and density dependences were obtained. Tensile strength was determined along and across the direction of formation for relatively different types of products. For all types of products, the short-term water absorption of the specimens was determined by partial immersion in water, and the results were compared. During the flammability tests, the flame propagation time on the specimen surface and the fact of incineration after removal of the flame source were determined for all types of specimens. [ABSTRACT FROM AUTHOR]

This study summarizes the state-of-the-art research progress concerning the influence of high-temperature exposure on the residual bond strength of steel rebar. Also, an experimental database from the literature was collected and analyzed for use in fire safety management in concrete design codes and specifications for high important reinforced concrete (RC) structures, such as public health-care buildings, to reduce and mitigate the risk of thermal damages, especially in steel-congested areas. Different vital variables are debated in the present review, including concrete cover-to-rebar diameter ratio, rebar deformation, fiber addition, transverse confinement, aggregate type, concrete water-to-binder ratio, concrete type, cooling regime, thermal loading regime, and heating exposure time. The review shows that high-temperature exposure significantly reduces the residual bond strength. It is concluded that increasing concrete cover, the addition of fibers, considering transverse confinement, using deformed rebar instead of a plain one, using a concrete mixture with a lower value of w / c ratio, and air-cooling regime alleviate the detrimental influence of high-temperature exposure on the residual bond strength. Standing time can significantly recover the bond reduction as a healing period. Additionally, research gaps and the current conflicting results regarding some variables are drawn to be considered for future works. [ABSTRACT FROM AUTHOR]

Long span cable-stayed bridges face risks of fire and explosion accidents caused by vehicles transporting fuel or chemicals. Such accidents may lead to damage to the stay cables, which in turn reduces the load capability of the bridge. This report introduces a newly developed fire and blast protection system for the multi-strand stay cables of Rod El Farag Axis Bridge in Egypt. The protection system consists of a thermal insulation blanket wrapped on cables and a steel tube covered with an anti-blast layer. Fire and blast tests were carried out to verify the effectiveness of the developed protection system. [ABSTRACT FROM AUTHOR]

Den Gamle By (The Old Town) in Aarhus, Denmark, exhibits many valuable artefacts that are impossible to evacuate in an emergency. Studies were carried out to investigate whether it is possible to protect them in case of fire using a fire-retardant cover. In this experiment, eight different types of covers were tested in a realistic fire experiment. The results show that it is possible to find suitable materials for the protection of museum artefacts in the event of fire. [ABSTRACT FROM AUTHOR]

A new class of biobased composites with tailorable mechanical properties made of natural fibers, polylactic acid, and ferulic acid derivatives (FAD) is studied. FAD was used to develop composites with elastomeric properties like improved elongation at break and highly reversible deformation upon elongation. Composites were prepared using raw and enzymatically treated hemp fibers. The fibers were defibrillated due to the enzymatic treatment increasing their aspect ratio. The composites were characterized by their mechanical properties and their reaction to fire. No significant change in the dispersion of the fibers in the composites was reported. Homogenously dispersed crystallites of FAD were observed by scanning electron microscopy in the PLA matrix and at the interface between the PLA and the fibers, where they are suspected to increase the free volume in correlation with a decrease in mechanical properties following the increase in the aspect ratio of the fibers. FAD also degraded the reaction to fire of the material with an increase in 10% of the peak of Heat Release Rate (pHRR) in comparison to neat PLA. It also increased the charring residue up to 3 wt.%. A synergistic effect between FAD and the lignin increasing the charring residue is also reported. [ABSTRACT FROM AUTHOR]

A highly efficient and durable phosphorous-nitrogen (P-N) synergistic flame retardant containing ammonium phosphate active groups (AATMPEG) was synthesized and grafted onto cotton fabrics by P-O-C covalent bonding. In the synthesis process, the -P=O(OH)2 group on the flame retardant is esterified with ethylene glycol to reduce the influence of metal ions on the flame retardant of cotton fabric during washing. The limiting oxygen index (LOI) value of 25 wt% AATMPEG-treated cotton fabric reached 45.0% and remained at 33.0% after 50 laundering cycles (LCs). Scanning electron microscopy (SEM), energy dispersive X-ray spectrometer (EDS), and X-ray diffraction (XRD) results showed that the flame retardant successfully penetrated the fabric without affecting its surface morphology and crystal structure. Thermogravimetry (TG), cone calorimetry, and vertical flammability test results show that AATMPEG generates phosphoric acid or polyphosphoric acid during combustion, promoting the thermal degradation and dehydration of the cotton fabric. The AATMPEG does not use formaldehyde in the synthesis process, meeting environmental requirements. [ABSTRACT FROM AUTHOR]

A novel formulation of the sodium lignin sulfonate (SLS) [bio based branched chain lignin polymer modified with the sulfonic acid] and the pomegranate rind extract (PRE), a wastage plant biomolecule, has been applied to the cellulosic cotton fabric to make it flame retardant. It was found that the control, 10% SLS and the PRE treated cotton fabric showed the limiting oxygen index (LOI) value of 18, 25, and 24, respectively and completely burnt within one to two minutes in the vertical flammability test. On the contrary, (PRE+ 10% SLS) treated cotton fabric showed 32% add-on and the LOI value of 32 with the specific char length of 40 mm after the completion of the vertical flammability test as per IS1871 method A. Extent of the afterglow duration and the char length, both have been decreased with increasing the percentage concentration of the SLS [5 to 10% (W/V)] into the PRE mixture. Thermo-gravimetry (TG) analysis of the control, PRE and the 10% SLS treated cotton fabric showed only 10% remaining char mass at 450°C in air atmosphere whereas the (PRE+ 10% SLS) treated fabric showed much lower mass loss rate and 45% remaining char mass at the said temperature. Moreover, the char morphology of the (PRE+ 10% SLS) formulation treated fabric showed structural integrity (weave of the fabric) with the presence of the small bubbles after the completion of the combustion phenomena. Mechanism of the fire retardancy revealed the fact that during the treatment, nitrogen containing alkaloids, long chain carbon molecule, poly phenolic compounds (present in the PRE) and the sulfur containing sulfonate groups, polyphenolic compounds (present in the SLS) deposited on the cotton fabric surface, combinedly acted on the flame retardancy (to arrest the both flame and the afterglow) and the char formation of the underlying cellulose structure, during burning. Moreover, the detail color values of the control and the treated fabrics also have been elucidated in the present research context. [ABSTRACT FROM AUTHOR]

In this work, the influences of the intumescent flame retardant (IFR) composed of tri-(2-hydroxyethyl) isocyanurate (THEIC) and ammonium polyphosphate (APP) on the coal were studied in order to effectively prevent and control the coal spontaneous combustion. The effects of IFR on the thermal behaviors of the coal were investigated by Kissinger and Flynn–Wall–Ozawa methods. The results have shown that the mass ratio of THEIC/APP = 1:2 has the best effect on the coal. It has a better carbonization performance and thermal stability at high temperature. The activation energy of the treated coal with 30 wt% IFR was increased up to 283.1 kJ/mol, indicating it is more difficult to be oxidized than that of raw coal (168.4 kJ/mol). At 200°C, the inhibition rate of coal treated by IFR reached approximately 56.5%. From fire extinguishing test, it can be found that an expanded carbonization layer was formed during the combustion for the treated coal with IFR which could effectively limit the transfer of heat, oxygen and combustible volatiles from the heat source to the coal, and prevent the coal from further burning. From this work, it is hoped to provide an efficient method to effectively prevent and extinguish the coal spontaneous combustion. [ABSTRACT FROM AUTHOR]

The American Society for Testing and Materials (ASTM), considered the gold standard worldwide, requires only testing in physiological saline solution to simulate in vivo conditions in standard testing of spinal implants. We conducted an in vitro study to identify an industrial lubricant with characteristics that are most similar to those of biologically lubricating fat, blood, and tissue fluids. The use of such a material could standardize the results of in vitro mechanical tests for better clinical applications. Our study has shown that the lubricity of physiological saline was well below that of human soft tissues and tissue fluids, and among the motor oils, Castrol GTX3 provided a testing environment similar to that of a living organism. With the intention of standardizing and preventing a biological hazard, we have developed a reproducible mechanical testing proposal based on our experiments, which, in addition, would allow us to avoid many misunderstandings and contingencies. [ABSTRACT FROM AUTHOR]

Plasters are traditional surface finish materials in timber buildings. Today, the lack of fire performance data and design guidelines place such ecological materials at a disadvantage since plaster is not considered as a fire protection material for timber. This study aims to provide an up-to-date overview of performed fire tests accompanied by investigations on thermal properties of selected ready-mix clay and lime plasters. Design parameters of plasters for the fire design of timber structures are proposed following the safety philosophy of EN 1995-1-2. Numerical heat transfer simulations provide sufficient agreement with furnace test results for undercoat clay plaster. The mechanical fastening system of a plaster (e.g. reed mat) on timber demonstrates paramount importance when determining the charring rate of timber and the fall-off time of plaster. The structural integrity and fire performance of plasters should be further investigated due to their various recipes and numerous fastening systems on timber. Further research in full-scale is needed to confirm the recommended design parameters. [ABSTRACT FROM AUTHOR]

The aim of this paper is to present a fire test database on the collapse of a full-scale steel stiffened plate structure without passive fire protection under lateral patch loading. Steel plate panels of an as-built 1900 TEU containership in compliance with test facility in a maximum size and capacity were considered as a reference structure, with principal dimensions of 7 m long and 4.8 m wide fitted with two transverse frames and seven longitudinal stiffeners. Lateral patch loading was applied using two loading actuators at the centre of each transverse frame. A fire test was conducted in a furnace fuelled by liquefied petroleum gas, where the maximum gas cloud temperature inside the furnace was increased up to 800°C during testing. Time history of the lateral deformations of the test structure was measured with the focus on a critical period of time until the structure reached the ultimate limit state (or collapse) after the fires started. Details of the test database are documented, which will be useful for validating computational models for structural failure analysis in fires. [ABSTRACT FROM AUTHOR]

This paper is a sequel to the authors' article on a full-scale fire testing to collapse of a steel stiffened plate structure without passive fire protection (PFP) under lateral patch loading (Paik JK, Ryu MG, He KH, Lee DH, Lee SY, Park DK, Thomase G. 2020. Full-scale fire testing to collapse of steel stiffened plate structures under lateral patch loading (Part 1) – without passive fire protection. Ships Offshore Struc. doi:). The test structure represents steel plate panels of a 1900 TEU containership in compliance with test facility in a maximum size and capacity. The aim of this paper is to experimentally examine the effects of PFP application on the fire collapse of steel stiffened plate structures. For this purpose, two transverse frames (primary strength members) of the test structure were insulated by cerawool which is a fire protection material. A fire test was conducted in a furnace burnt by liquefied petroleum gases. Structural collapse was monitored at discrete time intervals from when the fire started until the test structure entirely collapsed. The effect of fire-protected transverse frames on the structural collapse was investigated by comparison with test results on the structure that was unprotected from the fires. [ABSTRACT FROM AUTHOR]

Background: Adequate sedation is important for the treatment of ICU patients. AnaConDa (Anesthetic-Conserving-Device; ACD; Sedana Medical, Sweden), connected between ventilator and the patient, retains isoflurane during expiration, and releases it back during inspiration. The reflection efficiency (RefEff) corresponds to the percentage of expired anesthetic molecules that are re-inspired. We compared RefEff of AnaConDa-S (ACD-50) and AnaConDa-100 (ACD-100) under laboratory (DRY) and simulated clinical conditions (CLIN) using a test lung. Methods: Measurements were made under DRY and CLIN, with different tidal volumes (TV: 300 mL & 500 mL) and infusion rates (0.5–10 mL·h−1). RefEff was calculated from the isoflurane concentration in the test-lung (CISO) and plotted against the anesthetic vapor volume exhaled in one breath (V-exh = CISO·TV). Results: DRY: RefEff of both devices was ≈90% over a wide range of V-exh, but decreased when V-exh exceeded 5–7 mL (ACD-50) or 10–15 mL (ACD-100). CLIN: RefEff of ACD-50 was 70–80% (ACD-100: 80–90%), decreasing gradually with increasing V-exh. For 1 Vol.% isoflurane at TV500, the infusion rate with ACD-50 was twofold higher compared to ACD-100 (4 versus 2 mL·h−1). Conclusion: Under DRY and concentrations <1.5 Vol.%, RefEff of both devices is around 90%. Under CLIN, ACD-100 performs better with RefEff between 80% and 90% (ACD-50:70–80%), decreasing with increased vapor volume exhaled in one breath. [ABSTRACT FROM AUTHOR]

Spray fire is one of the most frequent fire accidents in ship engine compartments, drawing much attention to spray fire safety. Currently, a series of spray fire tests was conducted in a 2.0 m (L) × 2.0 m (W) × 1.88 m (H) enclosed compartment. Experimental results indicate that the combustion process can be divided into three stages and the injecting pressure has significant effect on the flame height, gas temperature, oxygen concentration, etc. The dimensionless flame height is proportional to the 1/9 power of the dimensionless heat release rate. With the increase in injecting pressure, both the slope of gas temperature rise and maximum average gas temperature increase, meanwhile the corresponding oxygen concentration and average oxygen concentration all decreases linearly. For estimating the average gas temperature and average oxygen concentration, two corresponding equations were established and verified by the current measured data. Moreover, the dimensionless gas temperature correlates well with the dimensionless oxygen concentration. [ABSTRACT FROM AUTHOR]

This paper highlights the nature of the problem related to tunnel liners exposed to fire, and presents a possible approach for assessing the static behaviour of concrete structures under this extreme loading condition. The paper starts with some comments regarding material parameters for concrete subjected to high temperatures proposed by the European Standards. Subsequently, the main aspects to be considered in a structural fire analysis for a tunnel are highlighted by means of a simple calculation scheme. Based on this scheme, an advanced calculation method for assessing the structural behaviour of concrete tunnel linings during a fire event is described and validated. The classic approach commonly used for structural static analyses based on thin elements (beam or shell) is not particularly suitable for determining section forces in concrete structures exposed to temperature changes. This limited adequacy emerges especially in the case of fire. In such cases, the impact of a temperature increase on the structural behaviour could be significantly overestimated. The proposed approach for tunnel fire verification, by properly considering the concrete cracking, provides more realistic results, avoiding unnecessary over-dimensioning of steel reinforcements in new structures, or the protection of existing structures by, for example, additional insulating layers. [ABSTRACT FROM AUTHOR]

Large suspension bridges are increasingly being exposed to greater fire risks as the volume of traffic carried by them increases. A serious truck fire in 2013 on the New Little Belt Bridge in Denmark threatened the integrity of the bridge due to fire exposure of the main cable at its lowest point. Compared to fuel tankers, the relatively high number of trucks carrying normal but flammable goods makes serious truck fires more likely. Such fires can lead to strength reduction or cable failure that could result in a reduction in bridge load rating and the need for long-lasting repairs. A concept and design for passive fire protection for main cables of large suspension bridges have been developed, tested and implemented. Two major Danish suspension bridges have been retrofitted with this design. The type and extent of fire protection are established through risk analyses, fire testing and investigations involving the cable steel, the fire protection material and the installation method. The extent of emergency preparedness and the timeline for fire-fighting actions are also taken into account. This paper describes a systematic approach to design, evaluate and provide fire protection systems for suspension bridge main cables. [ABSTRACT FROM AUTHOR]

Owing to their wounding potential, airguns are regarded as controlled firearms in some countries. In this study, aluminium witness plates were used to evaluate the wounding potential of airguns. A series of firing tests were conducted using six airguns and ten types of projectiles. The velocity and energy density (ED) of the projectiles fired at the witness plates were determined using a ballistic chronograph and high-speed camera. The ballistic limits (V50 and ED50) of the witness plate for the different projectile types were also obtained. V50 and ED50 were found to be within 86.0–167.0 m/s and 13.2–21.6 J/cm2, respectively. The percentage differences between V50 and the predicted threshold velocity for skin perforation were found to be <13%. These results demonstrate the suitability of the witness-plate method for evaluation of wounding potential. A Student's t-test of the ED50 between paired projectiles further indicated a statistically significant influence of the projectile material and structure on ED50, attributable to the deformation of the projectiles and the local-heat effect of the witness plates. The obtained results indicated that steel ball- and lead ball-type projectiles are most suitable for the wounding potential evaluation of smooth-bore BB guns and airguns with rifled barrels. [ABSTRACT FROM AUTHOR]

On an average, about 2% of a country's GDP is currently being spent for fire safety. The flammability of textile materials, ecofriendly flame-retardants (FR) and developing the dynamic testing protocol for diversified applications, now becoming a matter of growing concern for the prevention of fire hazards, burns, loss of life and property. Development of materials of inherent flame retardant fibre polymer or flame-retardants (FR) finish is useful for suppressing flame propagation in order to ensure protection against the hostile environment. There are various standard test protocols for the measurement of flaming exposure, ignition temperature, ignition time, flame time, char length, char area, mass loss, etc. However, more accurate and objective measures such as flame propagation rate, flame area catch up are also crucial for objective computation and visualization of flammability profile of the material. In this study, a simple scalable and multi-sample flammability testing equipment aided by video image processing was developed and evaluated. The processing of extracted flame images from the video for better segmentation of a generic fire pattern reported earlier to be complex and challenging. We tried various colour space transformations to obtain a simpler processing instead. It is observed that the transformation of NTSC luminance (Y) and chrominance (I and Q) color components have shown the better results for extracting flame parameters which is congruent with visual inspection. We employed it for obtaining and visualizing an objective and more meaningful flammability profile of textiles that current existing standards lack. Typical cases such as flame area propagation; evaluation after washing, testing of the shrunken area of FR treated textiles and visualization of segmented flame are demonstrated. [ABSTRACT FROM AUTHOR]

Sustainable uses of the struvite (magnesium ammonium phosphate hexahydrate, MgNH4PO4·6H2O, MAP) recovered from the synthetic wastewater, as a high-quality slow-release fertilizer for the growth of nine medicinal plants and a fire-retardant barrier on the flammability of cotton fabric and wooden plate, were explored in this study. The previous experimental results demonstrated that under the optimal conditions, about 98.7% of NH 4 + − N (initial NH 4 + − N = 1000 mg/L) could be effectively and successfully recovered from simulated wastewater in the form of MAP precipitate. Rates of increase in total fresh weights, total dry weights, and fresh heights of plants grown in soil fertilized with the struvite were determined as 67%, 52%, and 12% for valerian; 121%, 75%, and 18% for cucumber; 421%, 260%, and 47% for dill; 314%, 318%, and 27% for coriander; 432%, 566%, and 30% for tomato; 285%, 683%, and 26% for parsley; 200%, 225%, and 9% for basil; 857%, 656%, and 92% for rocket; and 146%, 115%, and 28% for cress, respectively, compared to the control pots. The microstructure, elemental composition, surface area, thermal behaviour, and functional groups of the grown crystals were characterized using SEM, EDS, BET, TGA-DTG-DSC, and FTIR analyses, respectively. Flammability tests and thermal analyses concluded that the dried and crumbled/implanted form of struvite used as a fire-retardant barrier demonstrated a remarkable flame-resistant behaviour for both cotton fabric and wooden plate. Findings of this experimental study clearly corroborated the versatility of struvite as non-polluting and environmentally friendly clean product for the sustainable usage in different fields [ABSTRACT FROM AUTHOR]

The possibility of organizing a continuous-detonation combustion of a liquid fuel film in an annular combustor of a detonation liquid-propellant rocket engine has been demonstrated. The near-limit mode of the longitudinally pulsating "film" detonation and the continuous spinning "film" detonation modes with one and two detonation waves circulating in the annular gap of the combustor are recorded in the fire tests. [ABSTRACT FROM AUTHOR]

To demonstrate printability and fire performance of 3D printable fibre reinforced cementitious materials at elevated temperatures, large-scaling printing and fire performance testing are required for engineering applications. In this work, a mixture design of 3D printable fibre reinforced cementitious composite (3DPFRCC) for large-scale printing was developed. A structure with dimensions of 78 × 60 × 90 cm (L × W × H) was printed by a gantry printer in 150 min, which demonstrates that the developed 3DPFRCC mixture possesses good buildability. The rheological property, setting-time, and mechanical properties under normal and elevated temperatures of the developed 3DPFRCC were then characterised. Final results indicate that the developed 3DPFRCC is suitable for engineering applications due to its good printability and mechanical properties under normal and elevated temperatures. [ABSTRACT FROM AUTHOR]

Nano-kaolinite was applied to lightweight wool fabric for imparting fire retardant finish using pad batch as well as exhaust method. The effect of fire retardant treatments on the physico-mechanical properties of wool fabric was studied in detail. Nano-kaolinite incorporated fire retardant formulations showed high fire retardant performance in terms of inclined flammability test, limiting oxygen index (LOI) and thermogravimetric analysis. The characterization of nanoparticles was performed using various analytical instruments. The results inferred that nano-kaolinite treatment by both application methods is effective for improving the fire resistance of wool fabric. The treatment resulted up to 32% enhancement in fire retardant properties. [ABSTRACT FROM AUTHOR]

Cross-laminated timber (CLT) is a popular engineered wood product for loadbearing wall, floor and roof elements to realise innovative and high-quality modern timber structures. The behaviour of CLT panels exposed to fire requires careful evaluation to allow the expansion of CLT elements' usage in buildings. This paper first presents a new charring model for timber in general and CLT specifically, based on the results of numerous fire tests with c Lt and the current fire design according to EN 1995-1-2. In addition, the char depth obtained from numerous fire tests with CLT is compared with results based on a charring model from Europe. [ABSTRACT FROM AUTHOR]

An experimental study has been conducted to investigate the dynamics of an extreme fuel-rich throttleable rocket engine during continuously throttling process. The rocket engine burned kerosene (RP-1) and oxygen and it was continuously throttled in fire tests by adjusting the flow rate of kerosene. Dynamic response of chamber pressure was analyzed. Results show two phenomena named hysteresis of characteristic velocity and anti-regulation of chamber pressure during the throttling process. When characteristic velocity hysteresis occurs, transient characteristic velocity is higher in condition of increasing mixture ratio (MR) and lower in condition of decreasing MR than steady value during throttling process. The anti-regulation can be induced by throttling or purging process. In addition, both throttling method and throttling rate influence the amplitude and duration of anti-regulation. Finally, the response of chamber pressure to the throttling was divided into two periods, namely ramp response and step response. From the step response, the combustion system is characterize as a first order system with a time constantT= 133 ms. [ABSTRACT FROM AUTHOR]

Difunctional boron-containing reactive flame retardant for UV-curable epoxy acrylate oligomer was synthesized from phenyl boronic acid and glycidyl methacrylate. The synthesized reactive diluent was utilized to formulate ultraviolet (UV)-curable wood coatings. The weight fractions of reactive diluent in coatings formulation was varied from 5 to 25 wt % with constant photoinitiator concentration. The molecular structure of reactive flame retardant was confirmed by Fourier-transform infrared, Nuclear magnetic resonance (NMR) and 11B NMR spectral analysis. Further, the efficacy of flame retardant behaviour of coatings was evaluated using limiting oxygen index and UL-94 vertical burning test. Thermal stability of cured coatings films were estimated from thermogravimetric and differential scanning calorimetry analysis. The effects of varying concentration of reactive diluent on the viscosity of coatings formulation along with optical, mechanical and chemical resistance properties of coatings were also evaluated. The coatings gel content, water absorption behaviour, contact angle analysis and stain resistance were also studied. [ABSTRACT FROM AUTHOR]

A test was conducted in this paper to learn the fire-resistant performance of cotton straw brick wall. According to the thickness of current non-load-bearing wall, selecting the size of 200 mm × 400 mm × 200 mm of cotton straw bricks tie into 250 mm × 450 mm × 625 mm wall as the test components. According to the construction of fire test method part 8: non-bearing the special requirements of vertical separation of components (GB/T9978·8-2008) to study the fire integrity and fire insulation, judge the duration of fire resistance of the specimen. The test results show that the non-load-bearing wall with small size high density cotton grass brick has a good fire-resistant performance, and the duration of fire resistance is more than 70 minutes. [ABSTRACT FROM AUTHOR]

According to IAEA regulation, type B packages are designed to withstand a fire test following the mechanical tests, simulating accident conditions during transport. The wood of the shock absorber located near the damage zones produced by these tests may ignite and the conditions of air accessibility inside the absorber could mean that wood smouldering persists during the cooling period. IRSN has conducted an experimental study in which a real scale shock absorber specimen has been exposed to a large scale heptane pool fire test. A dedicated facility makes it possible to simulate the thermal power of the package contents and to measure in real time the heat transfer at the rear surface of the absorber. After a pool fire of 35 min duration, wood combustion continued for four days. Significant values were measured on the contact surface between lid and shock absorber for heat flux (up to 8 kW m−2) and temperatures (reaching 460°C). The impact of wood smouldering induced heat fluxes on typical lid gaskets has also been evaluated. [ABSTRACT FROM AUTHOR]

The thermal response of a fiber reinforced polymer composite was measured by the bench-scale Cone Calorimeter and Intermediate-scale Calorimeter (ICAL) fire experiments. Finite-rate and infinite-rate pyrolysis models were used to predict the response of the composite panels under the same thermal boundary conditions as in the fire tests. It was shown that both models can give acceptable temperature, mass loss, and effective char thickness predictions. The effect of internal gas convection on thermal response predictions was determined insignificant at low heat flux levels. The thermal insulation at the back surface of the composite panel significantly increased both temperature and mass loss predictions. [ABSTRACT FROM PUBLISHER]

A test set-up in intermediate scale was conceived to investigate the structural integrity of materials under fire. The task was to develop a realistic test scenario targeting component-like behaviour. Carbon-fibre-reinforced sandwich specimens (500 × 500 × 20 mm) were used to examine failure mechanisms, times to failure and critical failure loads under compression. Fire tests were performed with fully developed fire applied to one side of the specimen by an oil burner. In a first test series, the applied load was varied, but the fully developed fire remained unchanged. In general, times to failure were short. Decreased load levels resulted in prolonged times to failure and led to a different failure mechanism. Results obtained in the test series were compared with a bench-scale study (150 × 150 × 20 mm) investigating identical material. The comparison clearly revealed the influence of size on the time to failure and the load-bearing capacity. [ABSTRACT FROM PUBLISHER]

In this work a numerical study has been carried out to gain physical insight into the phenomena of opposed flow flame spread over an array of thin solid fuel sheets in a microgravity environment. The two-dimensional (2D) simulations show that the flame spread rates for the multiple-fuel configuration are higher than those for the flame spreading over a single fuel sheet. This is due to reduced radiation losses from the flame and increased heat feedback to the solid fuel. The flame spread rate exhibits a non-monotonic variation with decrease in the interspace distance between the fuel sheets. Higher radiation heat feedback primarily as gas/flame radiation was found to be responsible for the increase in the flame spread rate with the reduction of the interspace distance. It was noted that as the interspace distance between the fuel sheets was reduced below a certain value, no steady solution could be obtained. However, at very small interspace distances, steady state spread rates were obtained. Here, due to oxygen starvation the flame spread rate decreased and eventually at some interspace distance the flame extinguished. With fuel emittance (equal to absorptance) reduced to ‘0’ the flame spread rate was nearly independent of the interspace distance, except at very small distances where the flame spread rate dropped due to oxygen starvation. A flame extinction plot with the extinction oxygen level was constructed for the multiple-fuel configuration at various interspace distances. The default fuel with an emittance of 0.92 was found to be more flammable in the multiple-fuel configuration than in a single fuel sheet configuration. For a fuel emittance equal to zero, the extinction oxygen limit decreases for both the single and the multiple fuel sheet configurations. However, the two flammability curves cross over at a certain fuel separation distance. The multiple-fuel configurations become less flammable compared to the single fuel sheet configuration below a certain separation distance. [ABSTRACT FROM PUBLISHER]

The article presents a study which describes the load resistance behavior of the uncharred residual cross section of timber structures subjected to fire. The researchers have conducted a series of experiments on the stiffness, strength, and limitations of glued laminated timber models at high temperatures. The findings reveal the behavior and residual fixed value of timber frames exposed to a fire and provide important insight for structural designs.

The article presents a study which describes the structural fire design and optimization of the Maison de la Paix building in Geneva, Switzerland. The researchers have analyzed the high-quality architecture in terms of stiffness, strength, and resistance of the structure and sub-structures at high temperatures. The findings describe the resistance behavior of optimized steel structures exposed in fire and provide an important insight for structural designs.

The article presents a study which describes the behavior of an office building with long-span cellular floor beams subjected to fire in Auckland, New Zealand. The researchers have conducted a series of experiments on the stiffness, strength, and deformation capacity of building materials using finite element simulations at high temperatures. The findings reveal the behavior of building structures with cellular beams exposed to fire and provide important insight for structural designs.

The article presents a study which describes the thermal behavior of cross-laminated timber floor panels in timber structures subjected to fire. The researchers have conducted a series of experiments on the stiffness, strength, and limitations of wooden structures at high temperatures. The findings reveal the thermal behavior and mechanical properties of timber structures exposed to fire and provide important insight for structural designs.