Fire Safety Journal最新文献

{"title":"Nonlinear impacts of fuel load on rate of spread and residence time in forest surface fires","authors":"Haiyan Wang,&nbsp;Junzhao Zhang,&nbsp;Cheng Fan,&nbsp;Hongbin Zhong,&nbsp;Lei Chen,&nbsp;Sixuan Huang,&nbsp;Mengen Zhao","doi":"10.1016/j.firesaf.2025.104404","DOIUrl":"10.1016/j.firesaf.2025.104404","url":null,"abstract":"<div><div>Frequent and extreme forest fires not only damage the environment but also pose a serious threat to firefighting personnel. Understanding the rate of spread (ROS) is crucial for developing effective firefighting strategies. Surface fuel load serves as the foundation for forest combustion, yet its effect on the ROS of surface fires remains contentious. To investigate the impact of fuel load on surface fire ROS, this study uses pine needles as the fuel material, simulating the accumulation of surface combustibles in forests by increasing fuel load, while also examining fuel depth and packing ratio under each load condition. Using an experimental system capable of measuring the ROS at multiple points along the fire line, we evaluated the ROS of surface fires within a fuel load range of 0.4–3.0 kg/m². The effects of packing ratio and fuel depth on ROS under different load conditions were discussed, and the influence of fuel load on fire line residence time was also explored. The results indicate that increasing fuel load leads to higher packing ratios and greater fuel bed depth due to the compressibility and weight of the pine needles. Within the studied load range, ROS does not follow a simple linear trend; instead, it initially rises, then decreases, and finally shows a slow increase. This non-linear behavior arises from the combined, and at times opposing, effects of packing ratio and fuel depth on ROS. Additionally, as fuel load increases, the residence time of the fire line follows a pattern of slow increase, sharp rise, and gradual further increase. The growth in flame depth, driven by higher fuel loads, ultimately becomes the dominant factor in prolonging the residence time. These findings provide valuable experimental data to enhance the understanding of forest surface fire dynamics and fuel load effects.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"155 ","pages":"Article 104404"},"PeriodicalIF":3.4,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143874182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Environmental impact of sprinklers and gravity smoke vents interaction — Review and probabilistic modelling approach","authors":"Wojciech Kowalski,&nbsp;Adam Krasuski,&nbsp;Wioletta Rogula-Kozłowska","doi":"10.1016/j.firesaf.2025.104386","DOIUrl":"10.1016/j.firesaf.2025.104386","url":null,"abstract":"<div><div>In the event of a fire in a typical industrial building, the systems deployed first are sprinklers and gravity smoke vents. Scientists and experts have not reached a firm consensus on the advantages or disadvantages of using sprinklers and gravity smoke vents together. While life-safety and property protection aspects have been already investigated, the environmental impact of these interactions has not yet been considered in research. This study identified and meticulously analysed several environmental issues related to the cooperation of these FPSs. A probabilistic model was then developed to efficiently assess emissions of selected pollutants from fires. The focus was on priority pollutants in terms of climate, toxicity and carcinogenicity. Various cost-optimization and monetization techniques were assessed to propose an appropriate method for evaluating the environmental impact of FPSs. A generic warehouse case study was conducted, comparing 24 different storage and FPS configurations. The applicability of the proposed approach was confirmed; however, the case study results indicates that the interference between sprinklers and gravity smoke vents is relatively insignificant compared to other factors. Additionally, four configurations of sprinklers and vents application were analysed. Sprinklers only have the lowest impact on environment for generic warehouse.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"154 ","pages":"Article 104386"},"PeriodicalIF":3.4,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143867690","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of laps on the behaviour of a composite slab under membrane action in fire","authors":"Moe Horie ,&nbsp;Takeo Hirashima ,&nbsp;Haruka Kanada ,&nbsp;Yusuke Shintani ,&nbsp;Kei Kimura","doi":"10.1016/j.firesaf.2025.104401","DOIUrl":"10.1016/j.firesaf.2025.104401","url":null,"abstract":"<div><div>Membrane action increases the load-bearing capacity of a two-way slab due to increased deflection. The composite slab must transfer enough tensile forces at the laps of reinforcements to ensure adequate load-bearing capacity under membrane action. This study conducted load-bearing fire tests on a large-scale floor system consisting of steel beams and a composite slab with welded wire mesh of guaranteed welded point strength in order to investigate the transfer of tensile forces within the laps under the membrane action. The lap length of meshes was the wire spacing plus 50 mm (150 mm), shorter than the 250 mm specified by 1992-1-1. Two specimens were subjected to loads that were tested with either 2 or 2.67 times the predicted load based on yield line theory. The floor system of the test specimens resisted the load not only during the 216-min heating phase but also during the cooling phase, despite experiencing the integrity failure. The temperature of the welded wire mesh exceeded 600 °C, and the maximum vertical deflection was 1/11 of the short span. The wires outside the lap failed, and the laps transferred sufficient tensile forces until the wires yielded. Therefore, the lap length of the wire spacing plus 50 mm (150 mm) was adequate for transferring tensile forces. The test results indicated that the load-bearing capacity of the floor system based on ECCS was conservative, considering the strength degradation of the welded wire mesh at high temperatures.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"154 ","pages":"Article 104401"},"PeriodicalIF":3.4,"publicationDate":"2025-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143859485","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The performance of hot-dip galvanized composite beams made of high and higher strength steel in standard fire resistance tests","authors":"Maria-Mirabela Firan ,&nbsp;Justus Frenz ,&nbsp;Jie Li ,&nbsp;Annika Kapfhammer ,&nbsp;Luke Bisby ,&nbsp;Jochen Zehfuß ,&nbsp;Martin Mensinger","doi":"10.1016/j.firesaf.2025.104400","DOIUrl":"10.1016/j.firesaf.2025.104400","url":null,"abstract":"<div><div>The lower emissivity of hot-dip galvanized steel sections as compared with non-galvanized steel, particularly at temperatures below 500 °C, results in slower heating when exposed to fire, thus enabling fire resistance ratings of R30 for compact cross-sections without additional passive fire protection. Using galvanized high and higher-strength steels allows R30 fire resistance to be achieved in composite beams more efficiently and cost-effectively. These ideas are investigated experimentally and via numerical analyses in this paper.</div><div>Large-scale standard fire resistance tests are presented to evaluate the performance of hot-dip galvanized composite beams under thermal and mechanical loads. The tests include a variety of beam geometries and depths, using steel grades S460M and S690QL. Single-symmetrical beams were designed with a reduced top flange thicknesses and compact bottom flanges to optimize overall depth and improve thermal response during fire testing. The temperature-dependent material properties of the S460M and S690QL steels is characterised, including steady state and transient tensile tests on both steels, and the results are compared with those given in DIN EN 1993-1-2. Hot-dip galvanized secondary beams with different connection types were connected in the middle of the beams during the large scale fire resistance tests so as to investigate temperatures experienced by differing connection details. The collected test data are used to validate and verify finite element models for such composite beams when exposed to standard fire exposures, alongside further parametric studies examining elements such as cross sectional geometry of the composite beam, the degree of shear connection, and the overall length of the beams. The outcomes of these studies contribute to the determination of the minimum required degree of stud shear connection for hot-dip galvanized composite beams in standard fire scenarios.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"154 ","pages":"Article 104400"},"PeriodicalIF":3.4,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143863452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lateral flame spread over thermally thin Fuels: Theoretical prediction of spread rate and experimental validation with PMMA and cellulosic fuels","authors":"Subrata Bhattacharjee,&nbsp;Felix Panzer,&nbsp;Simon Zielke","doi":"10.1016/j.firesaf.2025.104389","DOIUrl":"10.1016/j.firesaf.2025.104389","url":null,"abstract":"<div><div>Flame spread over solid fuel is a fundamental problem in fire safety science. Although it has been studied in different orientations – downward, upward, horizontal, and lateral– closed-form formulas for predicting the flame spread rate were first proposed for the opposed-flow configuration and experimentally verified in downward configuration, a special case of opposed-flow flame spread. In this work we present a simplified theory to predict the flame spread rate when a vertical flame spreads sideways (laterally) on both sides (symmetrically) of a thermally thin sample held horizontally in a quiescent normal-gravity environment. The ratio of flame spread rates between the lateral and downward orientations are shown to depend only on the flame coefficient, a non-dimensional known temperature ratio, and the Prandtl number. Experiments are performed in both downward and lateral configurations with a series of PMMA (Poly-methyl metacrylate) samples with fuel thickness ranging from 400 through 1500 μm and width from 10 through 60 mm as parameters. Similar experiments are also performed with ashless filter paper. The spread rate ratio between the two configurations is compared to the theoretical prediction with reasonable agreement. As predicted by the theory, the spread rate ratio is found to be independent of fuel thickness and fuel width for laminar flame spread.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"154 ","pages":"Article 104389"},"PeriodicalIF":3.4,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143863451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hybrid fire testing of concrete-filled steel tube columns: A large-scale experimental and numerical investigation","authors":"Majid Hamidi ,&nbsp;Masoud Adelzadeh ,&nbsp;Hamzeh Hajiloo","doi":"10.1016/j.firesaf.2025.104402","DOIUrl":"10.1016/j.firesaf.2025.104402","url":null,"abstract":"<div><div>Hybrid Fire Testing (HFT) integrates experimental fire testing with numerical simulations to better capture the interaction between a physical sample in a furnace fire and the structure that would surround it in real-world conditions. Unlike traditional fire testing, HFT enables a more accurate analysis of complex structural behaviours by simulating the effect of adjacent structural elements, thus providing a realistic assessment of a structure's fire performance. This paper presents a full-scale experimental hybrid fire test of a concrete-filled steel tube (CFST) column using an advanced HFT framework developed in previous research. A three-story, four-bay structure with the steel moment-resisting frame was selected for the validation. One column of the structure was physically represented in the laboratory, while the remainder of the structure was modelled numerically through finite element software. The physical specimen was heated following a standard fire curve. The experimental results are compared with numerical predictions and fire resistance tests of a similar single column to validate the performance of the developed method in full-scale applications. This comparison also provides insight into the performance of the column when acting as part of the larger structural system. The test results confirmed the proposed method can accurately simulate the complicated behaviour of a CFST column at high temperatures and subsequent failure.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"154 ","pages":"Article 104402"},"PeriodicalIF":3.4,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143843377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Susceptibility to ignition of landscaping mulches exposed to firebrand piles or radiation","authors":"Shaorun Lin ,&nbsp;Wuquan Cui ,&nbsp;Siyan Wang ,&nbsp;Yunzhu Qin ,&nbsp;Yuying Chen ,&nbsp;Yichao Zhang ,&nbsp;Xinyan Huang ,&nbsp;Stephen L. Quarles ,&nbsp;Michael J. Gollner","doi":"10.1016/j.firesaf.2025.104388","DOIUrl":"10.1016/j.firesaf.2025.104388","url":null,"abstract":"<div><div>Mulch products are widely used in landscaping at the wildland-urban interface (WUI), but burning mulch poses a significant ignition hazard to nearby structures. This study evaluates the ignition susceptibility of 10 mulches used in California, USA, exposed to smoldering firebrand piles or irradiation. The mulches included composted types, where products are piled and partially decomposed (bioretention, cal trans, marin vineyard, topper mulch, screened compost) and non-composted types (forest floor, redwood, black mulch, fir bark A and B). We found that all mulches except screened compost can be ignited to smolder by firebrand piles, with ignition more likely at higher firebrand mass and wind speeds. Following spotting ignition, non-composted mulches were more prone to transition from smoldering to flaming at critical wind speeds, which varied by mulch type. For piloted ignition, all mulches can sustain flames under irradiation, with non-composted mulches generally requiring lower critical heat fluxes due to the emission of more combustible gases. Particle size significantly influenced ignition thresholds, with smaller particles facilitating piloted flaming ignition and larger particles being more susceptible to spotting ignition and smoldering-to-flaming transition. This work deepens our understanding of ignition and burning behaviors of mulch, helping improve the prevention and suppression strategies against catastrophic WUI fires.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"154 ","pages":"Article 104388"},"PeriodicalIF":3.4,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143850494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of the influence of exhaust vent leakage on the efficiency of tunnel smoke evacuation","authors":"Xinyue Zhang ,&nbsp;Mingrui Luo ,&nbsp;Liangliang Tao ,&nbsp;Yanhua Zeng ,&nbsp;Yanping Yuan ,&nbsp;Zhen Zhang","doi":"10.1016/j.firesaf.2025.104399","DOIUrl":"10.1016/j.firesaf.2025.104399","url":null,"abstract":"<div><div>The ventilation section of an undersea road tunnel is extremely long. Air leakage from the exhaust vents significantly reduces the efficiency of the smoke exhaust system, which threatens the lives and safety of personnel. In this paper, a calculation model of exhaust vent leakage is established and the reliability of the calculation model is validated by field tests. Air leakage in the case tunnel reached 155.22 m³/s with a common type of exhaust vent, reducing the extraction efficiency of gas flow through smoke vents (extraction efficiency) by more than 40 %; the impact of air leakage cannot be ignored. The extraction efficiency of the exhaust vents is reduced from 89.59 % to 47.86 % as the leakage coefficient <em>K</em>_<em>0</em> increases from 3 to 24 for the same smoke exhaust volume. As the number of opened smoke vents decreases, the extraction efficiency of the tunnel decreases. When the smoke vent spacing increases from 50 m to 90 m, the extraction efficiency increases from 52.51 % to 69.35 %. The proposed calculation model, which considers exhaust vent leakage, is important for evaluating the efficiency of the smoke exhaust system and will help to optimize the tunnel's fire safety design. An exhaust vent leakage prediction formula of the whole tunnel is also proposed.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"154 ","pages":"Article 104399"},"PeriodicalIF":3.4,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143835069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Limiting lip-height of pool fires","authors":"Einar A. Kolstad ,&nbsp;Bjarne Chr. Hagen ,&nbsp;Kim Christensen ,&nbsp;Ulrich Krause ,&nbsp;Vidar Frette","doi":"10.1016/j.firesaf.2025.104385","DOIUrl":"10.1016/j.firesaf.2025.104385","url":null,"abstract":"<div><div>The lip height at which an unsteady pool fire self-extinguishes, called the limiting lip-height is investigated. Experiments have been conducted in 14 cylindrical containers with inner diameters from <span><math><mrow><mn>2</mn><mo>.</mo><mn>5</mn><mspace></mspace><mspace></mspace><mi>mm</mi></mrow></math></span> to <span><math><mrow><mn>400</mn><mspace></mspace><mspace></mspace><mi>mm</mi></mrow></math></span> and heptane as fuel. The dimensionless limiting lip-height (limiting lip-height divided by the container diameter) in unsteady pool fires increases from 2 for the smallest containers to almost 5 for the largest container. The values are higher than for corresponding experiments with steady pool fires (cold containers). The flame position and motion, laterally and vertically, are described. The fuel surface temperature increases weakly with container diameter.</div><div>Pool fires during industrial accidents and laboratory experiments will, in most cases, evolve according to an unsteady pool fire scheme with increasing lip height. For these situations, it is crucial to understand how various factors influence the evolution of the pool fire. Consequently, results are reported here for a wide range in container size.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"154 ","pages":"Article 104385"},"PeriodicalIF":3.4,"publicationDate":"2025-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143816476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Opposed flame spread over a thermally-thin charring material under varied flow velocities and ambient pressures in a narrow channel apparatus","authors":"Wenlong Wang ,&nbsp;Shangqing Tao ,&nbsp;Jun Fang ,&nbsp;Yi Zeng ,&nbsp;Jiyun Wang ,&nbsp;Yuhang Chen ,&nbsp;Feng Zhu ,&nbsp;Yueqin Zhu ,&nbsp;Aichun Liu ,&nbsp;Yongming Zhang","doi":"10.1016/j.firesaf.2025.104396","DOIUrl":"10.1016/j.firesaf.2025.104396","url":null,"abstract":"<div><div>The opposed flame spread over thermally-thin filter paper under constrained buoyancy at varied flow velocities and ambient pressures was investigated, which will be conducive to develop ground-based techniques for simulating microgravity. With increasing flow velocity, three regimes can be roughly identified: 1) near quenching regime, the periodic fingering flamelets appear for oxygen starvation, expanding the flammability range; 2) steady-state spreading regime, symmetric flames occur among the sample surface due to buoyancy suppression, and the flame spread rate reaches its peak; 3) near blow-off regime, the flame is affected by finite chemical kinetics. The whole pyrolysis region is identified into the primary/secondary pyrolysis regions characterized by blue/orange attached flames, and the frequent transformation between them intensifies the flame instability. With increasing flow velocity, the global equivalence ratio increases firstly and decreases finally under higher pressures, while decreases monotonously under lower pressures. The optimal utilization of the narrow channel apparatus for suppressing the buoyancy effect should be located in the range of moderate flow velocities far away from the extinction limits, where the heat loss effect of the parallel plates can be neglected. By tracking the extinction limit, the flammability boundary under different pressures was obtained. It is found that the quenching boundary is dependent on the diffusion rate of fuel vapor, while the blow-off boundary is determined by the critical global equivalence ratio. The flammability range narrows with the decreasing pressure, and relatively higher ambient pressure is required to achieve better effectiveness of simulating microgravity in future space missions.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"154 ","pages":"Article 104396"},"PeriodicalIF":3.4,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143824243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}