Fire Safety Journal最新文献_第5页

Applying timber-insulation mixed ceiling strategy in CFD simulation of large open-plan compartment with non-uniform fuel load 木材-绝热混合顶棚策略在非均匀燃油负荷大型开舱CFD模拟中的应用

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2026-01-01 Epub Date: 2025-11-26 DOI: 10.1016/j.firesaf.2025.104599

Cheng Chen , Felix Wiesner , Panagiotis Kotsovinos , Tianwei Chu , Yifan Nie , Asif Usmani , Liming Jiang

Engineered timber products are increasingly popular in modern architecture due to their sustainability, ease of installation, and visual appeal. However, the combustibility of exposed timber elements presents significant fire safety challenges, particularly in modern large open-plan compartments. Previous experiments demonstrate rapid fire spread once timber ceilings ignite, highlighting the urgent need for effective fire mitigation strategies. Using a CFD fire model validated against a full-scale compartment fire test, the performance of the previous study on the proposed design strategy for the ceiling involving a mixed surface of timber and non-combustible insulation strips, complemented by a reinforced concrete upper layer, for mitigating fire spread has been demonstrated. Given that real-world fuel distributions are often non-uniform, this research specifically further investigates the effectiveness of the mixed ceiling strategy under non-uniform fuel scenarios, which may pose higher fire risks than conventional uniform arrangements. Results confirm that the mixed ceiling effectively delays fire growth and maintains localized burning for extended periods, especially when coupled with optimized fuel spacing and enhanced ventilation conditions. Parametric analyses further reveal that increasing the proportion of insulation relative to timber enhances fire mitigation, even under extreme fire scenarios. The flexible design principles inherent to the mixed ceiling strategy thus provide substantial structural and safety benefits, demonstrating reliable performance under challenging fire scenarios and supporting performance-based fire safety design.

由于其可持续性、易于安装和视觉吸引力，工程木制品在现代建筑中越来越受欢迎。然而，暴露的木材元件的可燃性提出了重大的消防安全挑战，特别是在现代大型开放式隔间中。先前的实验表明，一旦木材天花板着火，火势会迅速蔓延，这突出了有效的防火策略的迫切需要。通过CFD火灾模型对全尺寸隔间火灾测试进行验证，先前对天花板设计策略的研究的性能得到了证明，该设计策略涉及木材和不燃隔热条的混合表面，并辅以钢筋混凝土上层，以减轻火势蔓延。考虑到现实世界的燃料分布往往是不均匀的，本研究专门进一步研究了混合天花板策略在非均匀燃料场景下的有效性，这可能比传统的均匀布置带来更高的火灾风险。结果证实，混合顶棚有效地延缓了火势的蔓延，并在较长时间内保持局部燃烧，特别是在优化燃料间距和增强通风条件的情况下。参数分析进一步表明，即使在极端火灾情况下，增加绝缘材料相对于木材的比例也能增强防火效果。因此，混合天花板策略固有的灵活设计原则提供了实质性的结构和安全优势，在具有挑战性的火灾场景下展示了可靠的性能，并支持基于性能的消防安全设计。

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引用次数: 0

Study on the effects of porous materials synergistically combined with inert gas on the explosion characteristics of combustible gas 多孔材料与惰性气体协同作用对可燃气体爆炸特性影响的研究

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2026-01-01 Epub Date: 2025-11-25 DOI: 10.1016/j.firesaf.2025.104598

Zehao Yin, Lingjun Xu, Zhi Zhai, Zengliang Zhang

To elucidate the combined influence of porous materials and inert gases on combustible gas explosions, a customized explosion pipeline system was designed to systematically investigate the effects of porous materials with varying pore densities (10-40PPI) and nitrogen concentrations on flame intensity, propagation velocity, structural dynamics, and overpressure. The results demonstrate a dual-mode interaction: 10PPI porous materials were found to exhibit flame-enhancing properties, amplifying combustion intensity, while higher pore densities (20-40PPI) were observed to transition from flame acceleration to suppression as pore dimensions approach or even falling below the methane quenching diameter. This transition mechanism is governed by dominant wall effects and thermal quenching. The addition of nitrogen was shown to further suppress upstream flame intensity and velocity through synergistic mechanisms, including radical scavenging, kinetic energy dissipation, and fuel dilution, resulting in a peak overpressure attenuation of 75.6 %. The optimal explosion mitigation was achieved using 40PPI porous materials and 10 % nitrogen concentration. This study provides a mechanistic framework for explosion suppression strategies, offering actionable insights for industrial safety applications.

为了阐明多孔材料和惰性气体对可燃气体爆炸的综合影响，设计了一套定制爆炸管道系统，系统研究了不同孔隙密度（10-40PPI）和氮气浓度的多孔材料对火焰强度、传播速度、结构动力学和超压的影响。结果显示了一种双模式相互作用：10PPI多孔材料表现出火焰增强特性，放大了燃烧强度，而更高孔隙密度（20-40PPI）的孔隙尺寸接近甚至低于甲烷淬火直径时，从火焰加速向抑制转变。这种转变机制受主导壁效应和热猝灭控制。结果表明，氮气的加入通过自由基清除、动能耗散和燃料稀释等协同机制进一步抑制了上游火焰强度和速度，峰值超压衰减75.6%。使用40PPI多孔材料和10%的氮浓度达到最佳的防爆效果。该研究为爆炸抑制策略提供了一个机制框架，为工业安全应用提供了可操作的见解。

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引用次数: 0

Characteristic Compartment Fire Behaviour — A theoretical study encompassing a broader range of regimes 特征隔间火灾行为-一个理论研究，包括更广泛的制度

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2026-01-01 Epub Date: 2025-11-10 DOI: 10.1016/j.firesaf.2025.104589

A.H. Majdalani , I. Calderón , W. Jahn , J.L. Torero

Scaling analysis is used to characterise a series of ten different possible compartment fire scenarios as a function of compartment geometry and ventilation. In addition to the classic scenarios corresponding to Regime I and Regime II fires, eight additional cases were analysed showing that the flow characteristics are generally a function only of the Froude and Euler non-dimensional parameters. All ten scenarios can be described or bounded by the two classic and limiting regimes of behaviour, nevertheless five intermediate scenarios require spatial resolution to achieve a precise characterisation. Therefore, simple scaling analysis appears sufficient to deliver an adequate assessment of all parameters needed to define the heat transfer from the fire to the compartment until burnout of the available combustible compartment contents. The present analysis highlights the specific areas where spatial resolution is required and the potential limitations associated to the use of more detailed tools, such as CFD, for quantification in these specific areas.

尺度分析用于描述一系列十种不同的可能的隔间火灾场景，作为隔间几何形状和通风的函数。除了对应于状态I和状态II火灾的经典场景外，还分析了另外8个案例，表明流动特性通常仅是Froude和Euler无量纲参数的函数。所有十种情景都可以用两种经典和限制的行为模式来描述或限定，然而，五种中间情景需要空间分辨率来实现精确的特征描述。因此，简单的尺度分析似乎足以提供所需的所有参数的充分评估，以确定从火到隔间的热量传递，直到可用的可燃隔间内容物燃尽。目前的分析强调了需要空间分辨率的特定领域，以及在这些特定领域使用更详细的工具（如CFD）进行量化的潜在限制。

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引用次数: 0

Numerical simulation of the action of fire-induced wind on wildfire behaviour 火致风对野火影响的数值模拟

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2026-01-01 Epub Date: 2025-11-11 DOI: 10.1016/j.firesaf.2025.104591

Gilbert Accary

The development of fire-induced wind and its action on wildfire behaviour are studied by numerical simulation of fire spread on sloping terrain. The simulations, conducted using a physics-based fire model, are based on a shrubland fire experiment carried out on a 28° sloping terrain under a 1.67 m/s wind-speed, resulting in a high-intensity fire (about 10 MW/m). Three lengths of the ignition line were considered: infinite fire line (simulated using periodic boundary conditions), 30-m-long fire line (as in the experiment), and 90-m-long fire line. Results show that fire-induced wind only occurs in the case of a large fire-front length and that its interaction with the fire front changes fire-spread regime. The highest intensity of fire-induced wind was obtained for an infinite fire front leading to a wind-driven fire with Byram's number less than 2. Induced wind was practically cancelled for a 30-m-long fire line as the fire draws fresh air into the flaming zone from the lateral sides, yielding a plume-dominated fire with Byram's number greater than 10. For a 90-m-long fire line, the intensity of fire-induced wind increased compared to the 30-m-long fire line case, resulting in a transitional fire-spread regime with Byram's number between 2 and 10.

通过对斜坡地形上火灾蔓延的数值模拟，研究了火风的发展及其对野火行为的影响。模拟使用基于物理的火灾模型，基于在28°斜坡地形上进行的灌木丛火灾实验，风速为1.67 m/s，导致高强度火灾（约10 MW/m）。考虑三种长度的着火线：无限火线（使用周期性边界条件模拟），30米长的火线（与实验一样）和90米长的火线。结果表明，火灾诱导风只在较大的火线长度下发生，其与火线的相互作用改变了火灾的蔓延状态。在无限火锋处，当拜拉姆数小于2时，火致风强度最大。在30米长的火线上，诱导风实际上被取消了，因为火焰从侧面吸引新鲜空气进入燃烧区域，产生了一种以羽状火焰为主的火灾，Byram数大于10。对于90米长的火线，与30米长的火线情况相比，火灾诱发风的强度增加，导致过渡的火灾蔓延状态，Byram数在2到10之间。

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引用次数: 0

The effect of water vapor on the flammability of fluorinated refrigerants 水蒸气对含氟制冷剂可燃性的影响

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2026-01-01 Epub Date: 2025-10-07 DOI: 10.1016/j.firesaf.2025.104553

Gregory T. Linteris , Michael J. Hegetschweiler , Valeri I. Babushok

Possible replacements for the refrigerant R-134a have been proposed in previous work based on their flammability behavior in standard tests of the Heating, Ventilation, Air-Conditioning, and Refrigeration industry. The present work extends that behavior to more extreme conditions of temperature and humidity based on estimates of the overall reaction rate of the mixtures obtained from perfectly-stirred reactor (PSR) model simulations. The PSR simulations were found to predict the flammability conditions of the standard test well. For initial temperatures of 23 °C–60 °C and water vapor volume fraction in the oxidizer of 0 %–10 %, the effect of humidity on the overall reaction rate is predicted to be much larger than the effect of temperature, with an increase in the overall reaction rate up to about 2.5–9 times with most moist flames as compared to dry.

基于R-134a在采暖、通风、空调和制冷行业的标准测试中的可燃性，在之前的工作中提出了制冷剂R-134a的可能替代品。目前的工作将这种行为扩展到更极端的温度和湿度条件下，基于从完全搅拌反应器（PSR）模型模拟中获得的混合物的总体反应速率估计。发现PSR模拟可以预测标准测试井的可燃性条件。当初始温度为23°C - 60°C，氧化剂中水蒸气体积分数为0% - 10%时，湿度对总反应速率的影响预计要比温度的影响大得多，与干燥火焰相比，大多数湿火焰的总反应速率可提高约2.5-9倍。

引用次数: 0

Cooling methods impact on post-fire residual bond properties of bimetallic steel bars in seawater concrete 冷却方式对海水混凝土中双金属钢筋火灾后残余粘结性能的影响

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2026-01-01 Epub Date: 2025-10-30 DOI: 10.1016/j.firesaf.2025.104569

Xuanyi Xue , Fei Wang , Jianmin Hua , Neng Wang , Shuang Yan

The bimetallic steel bar (BSB) is a new type of corrosion-resistant steel bar composed of stainless steel cladding and carbon steel substrate. In ocean engineering, the combination of BSB and seawater concrete can better utilize in-situ resources, and reduce the cost of seawater desalination and material transportation. To evaluate the residual bearing performance of the bimetallic steel bar-seawater concrete (BSBSC) structure post-fire, it is essential to elucidate the bond behavior of BSBSC exposed to elevated temperatures. In this study, the effects of high temperatures and cooling methods on the bond performance of BSBSC were investigated. The results indicated that the elevated temperature significantly weakened the bonding strength of BSBSC. The bonding strength of BSBSC exposed to 400 °C had decreased by a maximum of 63.54 %. As the temperature increased, the difference in bonding strength between air cooling and water cooling decreased from 27.61 % to 3.60 %. The peak-load slip initially declined and subsequently rose as the temperature increased with the transition temperature between 200 °C and 400 °C. A predictive bond stress-slip constitutive model for BSBSC was formulated. The design method for steel bar anchorage length in current design standards has been revised to take into account the fire risk.

双金属棒材（BSB）是一种由不锈钢包层和碳钢基体组成的新型耐腐蚀棒材。在海洋工程中，BSB与海水混凝土的结合可以更好地利用就地资源，降低海水淡化和材料运输的成本。为了评价双金属钢筋-海水混凝土（BSBSC）结构火灾后的残余承载性能，有必要研究高温下BSBSC的粘结行为。在本研究中，研究了高温和冷却方式对BSBSC粘结性能的影响。结果表明，温度升高显著降低了BSBSC的结合强度。BSBSC在400℃下的结合强度最大下降了63.54%。随着温度的升高，风冷与水冷的结合强度差由27.61%减小到3.60%。在200℃~ 400℃之间，随着温度的升高，峰载滑移量呈先下降后上升的趋势。建立了BSBSC的预测粘结应力-滑移本构模型。对现行设计标准中钢筋锚固长度的设计方法进行了修订，以考虑火灾风险。

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引用次数: 0

Experimental investigation on mechanical properties of cast steel at elevated temperatures 铸钢高温力学性能的试验研究

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2026-01-01 Epub Date: 2025-11-01 DOI: 10.1016/j.firesaf.2025.104571

Hongbo Liu , Bingxu Han , Liulu Guo , Zhihua Chen

Cast steel is extensively used in diverse building structures, especially for complex joints and members. To guarantee the safety of cast steel components during fire events, precise characterization of mechanical properties and constitutive behavior of cast steel at elevated temperatures is imperative. This study presents a comprehensive experimental investigation of G20Mn5N and G20Mn5QT cast steels. Key mechanical property indexes of cast steel at elevated temperatures were determined and compared to code-specified values and high-temperature data for conventional structural steels. Results indicate that the cast steels exhibited a blue brittleness phenomenon at 300 °C, characterized by increased ultimate strength and reduced toughness and ductility, ultimately predisposing them to brittle failure. Cast steel exhibited pronounced thermochromic behavior and ductile damage characteristics at elevated temperatures. With increasing temperature, the modulus of elasticity, yield strength, and ultimate strength of cast steel decreased, while elongation initially diminished before increasing. G20Mn5QT demonstrated superior fire resistance compared to G20Mn5N. Highly accurate empirical prediction equations for critical mechanical properties and theoretical stress-strain formulas at elevated temperatures were developed.

铸钢广泛应用于各种建筑结构，特别是复杂的接缝和构件。为了保证铸钢构件在火灾中的安全，精确表征铸钢在高温下的力学性能和本构行为是必不可少的。本文对G20Mn5N和G20Mn5QT铸钢进行了综合试验研究。测定了铸钢在高温下的关键力学性能指标，并与规范规定的数值和常规结构钢的高温数据进行了比较。结果表明，铸钢在300℃时表现出蓝色脆性现象，其特征是极限强度增加，韧性和延展性降低，最终导致脆性破坏。铸钢在高温下表现出明显的热致变色行为和延展性损伤特征。随着温度的升高，铸钢的弹性模量、屈服强度和极限强度下降，伸长率先降低后升高。与G20Mn5N相比，G20Mn5QT表现出更好的耐火性。建立了高精度的临界力学性能经验预测方程和高温下的应力-应变理论公式。

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引用次数: 0

The effect of the smoke alarm obligation – Experiences from Germany based on the data from 1998–2022 烟雾报警器义务的影响——基于1998-2022年数据的德国经验

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2026-01-01 Epub Date: 2025-11-11 DOI: 10.1016/j.firesaf.2025.104590

Sebastian Festag

Germany has had over 20 years of experience with the mandatory use of smoke alarms in households, apartments and residential areas. Since the first smoke alarm obligation (SAO), all federal states have now gradually stipulated an SAO in their building codes over different points of time and with different details. In addition to the positive experiences in concrete practical cases, in which smoke alarms warned people of fire, the effect of this regulation measure can be demonstrated statistically by analysing the development of fire fatality risks for Germany overall and in the individual federal states based on significance tests (t-tests). The benefit of this measure is occasionally questioned in public discussion, although the existing studies show positive effects. So far, there has not been sufficient experience or samples for all federal states to provide a statistical answer. The study presented here examines the impact of the SAO in Germany over the period from 1998 to 2022. Compared to previous analyses, this is the first time that data for the period from 2017 to 2022 are included in the analysis. This provides, a differentiation between the SAO for new buildings (SAO_NB) and existing buildings (SAO_EB). The result of the study shows a significant effect in Germany and in 12 of 16 federal states. The positive effects have increased in recent years, as can be seen in comparison with the latest analyses.

德国在强制在家庭、公寓和住宅区安装烟雾报警器方面已有20多年的经验。自第一个烟雾报警器义务（SAO）以来，所有联邦州现在都逐步在其建筑规范中规定了不同时间点和不同细节的SAO。除了在烟雾警报器警告人们注意火灾的具体实际案例中取得的积极经验外，还可以根据显著性检验（t检验）对整个德国和各个联邦州的火灾死亡风险发展情况进行统计分析，从而证明这一管制措施的效果。尽管现有的研究显示出积极的效果，但这种措施的好处偶尔会在公众讨论中受到质疑。到目前为止，还没有足够的经验或样本让所有联邦州提供统计答案。本文介绍的研究考察了1998年至2022年期间SAO对德国的影响。与之前的分析相比，这是第一次将2017年至2022年的数据纳入分析。这提供了新建筑（SAONB）和现有建筑（SAOEB）的SAO之间的区别。研究结果显示，在德国和16个联邦州中的12个州，这种做法产生了显著影响。从最近的分析可以看出，近年来积极的影响有所增加。

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引用次数: 0

Understanding the role of buoyancy and inertia in wind-aided vegetative fires 了解浮力和惯性在风助植物火灾中的作用

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2026-01-01 Epub Date: 2025-11-08 DOI: 10.1016/j.firesaf.2025.104588

Abhinandan Singh , Juan Cuevas , Reza Ziazi , Pedro Reszka , Albert Simeoni

The combined effects of buoyancy and inertia forces are studied for wind-aided vegetative fires. Two fuels - Pinus palustris (PP) and Pinus rigida (PR) are tested at five different wind conditions. The flame geometrical parameters are normalized using the flame height and scaled against the inverse of the Froude number (

Fr

). A power-law relationship is observed between all the flame geometrical parameters and

1 / Fr

. The instantaneous rate of spread is calculated using an image analysis algorithm by separating flame impingement and flame spread. The behavior of the average rate of spread is explored by evaluating radiative heat flux in the preheating region. The fluctuating rate of spread (

R^{'}

) is calculated from the instantaneous and average rate of spread values. The spectral analysis of

R^{'}

shows a range of frequencies that are an integer multiple (or harmonics) of the characteristic frequency for a given experiment. Strouhal number (St) evaluated using the characteristic frequency multiplied by the leaf area index of the pine needle bed shows a linear behavior against

1 / Fr

.

研究了风助植物火灾中浮力和惯性力的联合作用。两种燃料——palustris Pinus （PP）和Pinus rigida （PR）在五种不同的风力条件下进行了测试。火焰几何参数使用火焰高度归一化，并根据弗劳德数（Fr）的倒数进行缩放。火焰几何参数与1/Fr呈幂律关系。通过分离火焰撞击和火焰蔓延，采用图像分析算法计算瞬时传播速率。通过估算预热区的辐射热流密度，探讨了平均扩散率的变化规律。从差值的瞬时速率和平均速率计算差值的波动速率（R '）。R '的频谱分析显示了一个频率范围，它是给定实验的特征频率的整数倍（或谐波）。用特征频率乘以松针床叶面积指数计算的斯特劳哈尔数（St）与1/Fr呈线性关系。

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引用次数: 0

Impact of high-concentration smoke aerosols on radar electromagnetic wave propagation in building fire 高浓度烟雾气溶胶对建筑火灾中雷达电磁波传播的影响

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2026-01-01 Epub Date: 2025-11-03 DOI: 10.1016/j.firesaf.2025.104568

Song Wang , Jing Geng , Wenguo Weng

This study investigates the impact of high-concentration smoke aerosols on radar electromagnetic wave propagation in building fire scenarios. A computational model based on Mie scattering theory and existing databases was developed to evaluate the influence of smoke aerosols on radar signals. Additionally, a voxel-based Finite-Difference Time-Domain (FDTD) simulation method was designed to model complex random media, and simulations were conducted to validate the computational model. An experimental platform was also constructed to assess the impact of high-concentration smoke on radar electromagnetic waves, utilizing three types of radars: NVA-R641, X4M03, and IWR6843. Data collected under typical smoke conditions revealed attenuation coefficients of approximately 0.03 dB/m at 2.95 GHz, 0.37 dB/m at 8.75 GHz, and 0.76 dB/m at 60 GHz. These results support the theoretical model and demonstrate the feasibility of the simulation approach. This research provides a comprehensive framework for understanding and predicting the effects of high-concentration smoke aerosols on radar systems in building fire scenarios, offering valuable tools for optimizing radar performance and enhancing the reliability of life-saving operations in smoke-filled environments.

研究了建筑火灾场景下高浓度烟雾气溶胶对雷达电磁波传播的影响。基于Mie散射理论和现有数据库，建立了烟雾气溶胶对雷达信号影响的计算模型。此外，设计了一种基于体素的时域有限差分（FDTD）模拟方法来模拟复杂随机介质，并进行了仿真验证。利用NVA-R641、X4M03和IWR6843三种型号的雷达，搭建了一个实验平台来评估高浓度烟雾对雷达电磁波的影响。在典型烟雾条件下收集的数据显示，衰减系数在2.95 GHz时约为0.03 dB/m，在8.75 GHz时约为0.37 dB/m，在60 GHz时约为0.76 dB/m。这些结果支持了理论模型，并证明了仿真方法的可行性。本研究为理解和预测建筑火灾场景中高浓度烟雾气溶胶对雷达系统的影响提供了一个全面的框架，为优化雷达性能和提高烟雾弥漫环境中救生操作的可靠性提供了有价值的工具。

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引用次数: 0