Fire Safety Journal最新文献

Research on the framed glass under tilted installation: Thermal breakage mechanism 倾斜安装下框架玻璃的热破坏机理研究

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2026-01-09 DOI: 10.1016/j.firesaf.2026.104639

Yanni Zhang , Dan Yang , Shixi Nie , Yunchao Hou

Tilted glass is widely used in modern buildings, but its brittleness makes it prone to breakage in fires. This research used four-sided shielded glass as object, employing the self-built thermal radiation experimental bench to analyze the macro-fracture process of tilted glass, and using self-developed tilt effect + PFC2D coupling model, the micro-damage process was simulated. Results show the first breakage time of glass follows a trend of 200-290-227-188 s with inclination. At 0° and 5°, surface temperature and height factor exhibit a full-domain quadratic relationship, with cracks expanding from top to bottom. At 10° and 15°, a segmented quadratic relationship appears, and crack initiation shifts to bottom. Simulation results further indicate heating at 0° causes tensile stress to expand from the glass edges in a “ring” toward the center; at 10°, tensile stress acts vertically upward in a “relay” manner. Crack initiation temperature ranges are 100–210 °C for 0° and 210–320 °C for 10°. And revealed the evolution mechanism of glass microcrack loading behavior: microcracks mainly extend along grain boundaries in length and width, and glass structure becomes unstable when cracks connect in “polygonal crack network” morphology. The research findings provide a theoretical foundation for facade fire safety and fire accident investigation.

倾斜玻璃在现代建筑中得到了广泛的应用，但其易碎性使其在火灾中容易破碎。本研究以四面屏蔽玻璃为对象，采用自建热辐射试验台对倾斜玻璃的宏观断裂过程进行分析，并采用自行开发的倾斜效应+ PFC2D耦合模型对倾斜玻璃的微观损伤过程进行模拟。结果表明：玻璃的初次破碎时间随倾角的增大呈200 ~ 290 ~ 227 ~ 188 s的变化趋势；在0°和5°时，表面温度与高度因子呈全域二次关系，裂纹从上向下扩展。在10°和15°处，出现分段二次关系，裂纹萌生移至底部。模拟结果进一步表明，在0°温度下加热会导致拉应力从玻璃边缘呈“环形”向中心扩展；在10°时，拉应力以“继电器”方式垂直向上作用。裂纹起裂温度范围为：0℃时为100 ~ 210℃，10℃时为210 ~ 320℃。揭示了玻璃微裂纹加载行为的演化机制：微裂纹的长度和宽度主要沿晶界扩展，当裂纹以“多边形裂纹网络”形态连接时，玻璃结构变得不稳定。研究结果为建筑立面防火安全及火灾事故调查提供了理论依据。

{"title":"Research on the framed glass under tilted installation: Thermal breakage mechanism","authors":"Yanni Zhang , Dan Yang , Shixi Nie , Yunchao Hou","doi":"10.1016/j.firesaf.2026.104639","DOIUrl":"10.1016/j.firesaf.2026.104639","url":null,"abstract":"<div><div>Tilted glass is widely used in modern buildings, but its brittleness makes it prone to breakage in fires. This research used four-sided shielded glass as object, employing the self-built thermal radiation experimental bench to analyze the macro-fracture process of tilted glass, and using self-developed tilt effect + PFC2D coupling model, the micro-damage process was simulated. Results show the first breakage time of glass follows a trend of 200-290-227-188 s with inclination. At 0° and 5°, surface temperature and height factor exhibit a full-domain quadratic relationship, with cracks expanding from top to bottom. At 10° and 15°, a segmented quadratic relationship appears, and crack initiation shifts to bottom. Simulation results further indicate heating at 0° causes tensile stress to expand from the glass edges in a “ring” toward the center; at 10°, tensile stress acts vertically upward in a “relay” manner. Crack initiation temperature ranges are 100–210 °C for 0° and 210–320 °C for 10°. And revealed the evolution mechanism of glass microcrack loading behavior: microcracks mainly extend along grain boundaries in length and width, and glass structure becomes unstable when cracks connect in “polygonal crack network” morphology. The research findings provide a theoretical foundation for facade fire safety and fire accident investigation.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"161 ","pages":"Article 104639"},"PeriodicalIF":3.3,"publicationDate":"2026-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145928145","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}

引用次数: 0

A survey of commercial intumescent coating performance – contribution to the fire resistance of structural steel according to EN 13381 and BS 476 根据EN 13381和BS 476，对商业膨胀涂层性能的调查-对结构钢耐火性能的贡献

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2026-01-08 DOI: 10.1016/j.firesaf.2025.104631

Emil O. Lidman Olsson , Peter Arendt Jensen , Kim Dam-Johansen , Jochen A.H. Dreyer

The fire resistance of structural steel can be improved if it is coated with intumescent coating. Many intumescent coatings, tested according to standardized large-scale tests, are available on the market. In this work, data for 62 coatings, tested according to EN 13381-8 and/or BS 476-20/21, was compiled and analyzed. This was done to provide an overview of what fire-resistance performance can be expected from commercially available technologies and to identify trends in the data. The data shows that the fire resistance time tend to be 10–15 % lower when testing according to EN compared to BS. A comparison of data for rectangular and circular hollow sections reveals no consistent difference in fire resistance performance, indicating that any differences are a consequence of the individual coating behavior. For a given design temperature, the fire resistance time of I/H-sections is almost always higher compared to that of a corresponding hollow section. The difference was shown to be more pronounced at high section factors and/or low dry-film thicknesses. For I/H-sections, 3-sided exposure has a performance similar to 4-sided exposure, whereas rectangular hollow sections tend to have a somewhat higher fire-resistance with 3-sided exposure. Possible explanations for the observed trends are discussed in this review.

在结构钢表面涂上膨胀涂层，可以提高其防火性能。市场上有许多膨胀涂料，都是按照标准化的大型试验进行测试的。在这项工作中，根据EN 13381-8和/或BS 476-20/21对62种涂层进行了数据汇编和分析。这样做是为了概述商用技术的耐火性能，并确定数据中的趋势。数据表明，根据EN测试时，耐火时间往往比BS低10 - 15%。矩形和圆形空心截面的数据比较显示，耐火性能没有一致的差异，表明任何差异都是个别涂层行为的结果。在给定的设计温度下，I/ h型钢截面的耐火时间几乎总是高于相应的空心截面。这种差异在高截面系数和/或低干膜厚度时更为明显。对于I/ h截面，3面暴露的性能与4面暴露相似，而矩形空心截面在3面暴露时往往具有更高的耐火性。本文讨论了对观测趋势的可能解释。

{"title":"A survey of commercial intumescent coating performance – contribution to the fire resistance of structural steel according to EN 13381 and BS 476","authors":"Emil O. Lidman Olsson , Peter Arendt Jensen , Kim Dam-Johansen , Jochen A.H. Dreyer","doi":"10.1016/j.firesaf.2025.104631","DOIUrl":"10.1016/j.firesaf.2025.104631","url":null,"abstract":"<div><div>The fire resistance of structural steel can be improved if it is coated with intumescent coating. Many intumescent coatings, tested according to standardized large-scale tests, are available on the market. In this work, data for 62 coatings, tested according to EN 13381-8 and/or BS 476-20/21, was compiled and analyzed. This was done to provide an overview of what fire-resistance performance can be expected from commercially available technologies and to identify trends in the data. The data shows that the fire resistance time tend to be 10–15 % lower when testing according to EN compared to BS. A comparison of data for rectangular and circular hollow sections reveals no consistent difference in fire resistance performance, indicating that any differences are a consequence of the individual coating behavior. For a given design temperature, the fire resistance time of I/H-sections is almost always higher compared to that of a corresponding hollow section. The difference was shown to be more pronounced at high section factors and/or low dry-film thicknesses. For I/H-sections, 3-sided exposure has a performance similar to 4-sided exposure, whereas rectangular hollow sections tend to have a somewhat higher fire-resistance with 3-sided exposure. Possible explanations for the observed trends are discussed in this review.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"161 ","pages":"Article 104631"},"PeriodicalIF":3.3,"publicationDate":"2026-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979379","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}

引用次数: 0

Characteristics of water film flow on a vertical glass surface and its control of temperature rise in the glass 垂直玻璃表面水膜流动特性及其对玻璃温升的控制

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2026-01-04 DOI: 10.1016/j.firesaf.2025.104632

Shuo Zhang, Shuhei Sonobe, Yu-hsiang Wang, Yoshifumi Ohmiya

In this study, full-scale experiments were conducted to confirm the characteristics of water film flow on a vertical glass surface and quantitatively evaluate the effect of water film flow on controlling the temperature rise of the glass when heated by a fire plume. The velocity of the water film flow was measured to confirm that the flow was laminar. As the Reynolds number increased, the average flow velocity increased with a slope of approximately 2/3, while the film thickness increased with a slope of approximately 1/3. The measured temperature and incident heat flux were used to confirm the characteristics of the fire plume and the necessary water supply rate for heat shielding. Furthermore, a model was proposed for how the water film flow controls the temperature rise in the glass.

本研究通过全尺寸实验，确定了垂直玻璃表面的水膜流动特性，定量评价了在火焰羽流加热下，水膜流动对玻璃温升的控制效果。测量了水膜流的速度，证实了水膜流是层流。随着雷诺数的增加，平均流速以约2/3的斜率增加，膜厚以约1/3的斜率增加。通过测量温度和入射热流来确定火羽的特征和热屏蔽所需的供水量。此外，提出了水膜流动如何控制玻璃温升的模型。

引用次数: 0

Coupling effects of TPRD orifice diameter and residual hydrogen on deflagration overpressure peak in containerized transportation safety of HFCVs TPRD孔口直径和残余氢对重型燃料汽车集装箱运输安全爆燃超压峰值的耦合影响

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2025-12-30 DOI: 10.1016/j.firesaf.2025.104629

Xiaolong Jiang , Wei Qi , Yuqing Li , Xiangbin Zhao , Yingchen Hong , Yuejuan Li

When a hydrogen fuel cell vehicle (HFCV) is transported and an unintended hydrogen discharge occurs due to a fault scenario such as component aging, mechanical impact, or fire-induced TPRD activation, the peak deflagration overpressure depends on the remaining hydrogen quantity and TPRD diameter. Currently, neither TPRD diameters nor safe residual hydrogen levels during transport are standardized. To balance driving range and safety, numerical simulations were conducted to analyze peak overpressure under conservative accumulation–ignition conditions, examining various TPRD diameters and residual hydrogen levels. The results indicate that: Under the same residual hydrogen quantity, a significantly higher peak overpressure is produced during deflagration by a 5 mm TPRD orifice diameter compared to other smaller diameters. In the case of a TPRD with a diameter of 0.5 mm, the peak overpressure generated by the deflagration is significantly lower than that of larger diameters, and transport personnel have more time to respond to emergencies when the discharge occurs. Therefore, a higher residual hydrogen quantity is permissible.

当氢燃料电池汽车（HFCV）运输时，由于部件老化、机械冲击或火灾引起的TPRD激活等故障情况发生意外氢气排放时，爆燃峰值超压取决于剩余氢气量和TPRD直径。目前，TPRD的直径和运输过程中的安全残余氢含量都没有标准化。为了平衡续驶里程和安全性，采用数值模拟方法分析了保守蓄能点火工况下的峰值超压，考察了不同TPRD直径和残余氢含量。结果表明：在残余氢量相同的情况下，孔径为5mm的TPRD爆燃产生的峰值超压明显高于其他孔径较小的TPRD；在直径为0.5 mm的TPRD中，爆燃产生的峰值超压明显低于大直径的爆燃产生的峰值超压，并且在发生爆燃时运输人员有更多的时间来应对紧急情况。因此，允许较高的残余氢量。

{"title":"Coupling effects of TPRD orifice diameter and residual hydrogen on deflagration overpressure peak in containerized transportation safety of HFCVs","authors":"Xiaolong Jiang , Wei Qi , Yuqing Li , Xiangbin Zhao , Yingchen Hong , Yuejuan Li","doi":"10.1016/j.firesaf.2025.104629","DOIUrl":"10.1016/j.firesaf.2025.104629","url":null,"abstract":"<div><div>When a hydrogen fuel cell vehicle (HFCV) is transported and an unintended hydrogen discharge occurs due to a fault scenario such as component aging, mechanical impact, or fire-induced TPRD activation, the peak deflagration overpressure depends on the remaining hydrogen quantity and TPRD diameter. Currently, neither TPRD diameters nor safe residual hydrogen levels during transport are standardized. To balance driving range and safety, numerical simulations were conducted to analyze peak overpressure under conservative accumulation–ignition conditions, examining various TPRD diameters and residual hydrogen levels. The results indicate that: Under the same residual hydrogen quantity, a significantly higher peak overpressure is produced during deflagration by a 5 mm TPRD orifice diameter compared to other smaller diameters. In the case of a TPRD with a diameter of 0.5 mm, the peak overpressure generated by the deflagration is significantly lower than that of larger diameters, and transport personnel have more time to respond to emergencies when the discharge occurs. Therefore, a higher residual hydrogen quantity is permissible.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"161 ","pages":"Article 104629"},"PeriodicalIF":3.3,"publicationDate":"2025-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145928147","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}

引用次数: 0

Structural fire performance of RC beams via direct coupled temperature-displacement nonlinear simulation 钢筋混凝土梁结构防火性能的直接耦合温度-位移非线性模拟

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2025-12-30 DOI: 10.1016/j.firesaf.2025.104630

Mohamed Elshorbagi , Mohammad AlHamaydeh , Rafat Siddique

This research demonstrates the utility of the Direct Coupling Technique (DCT) for capturing the intricate, dynamic interplay between thermal and structural responses, particularly when fire induces significant geometric changes. Implemented in ABAQUS, the DCT integrates thermal and structural analyses, solving for temperature and displacement fields simultaneously. It incorporates critical material properties, including thermal conductivity, specific heat, density, stress-strain behavior, and thermal expansion, to model the performance of RC beams across heating, cooling, and post-fire phases. Validated against experimental data from two beams, one that failed during a fire and the other assessed for residual capacity, the approach proves highly accurate. Furthermore, validation of experimental data on an intumescent-coated steel substrate was conducted to demonstrate DCT's ability to capture the thermal-mechanical response for significant deformation problems, with an error of 3.4 % compared to 127.3 % for the Sequential Coupling Technique (SCT) model. A detailed parametric study further explores key factors, including concrete cover, lateral stiffness, and compressive strength, providing insights to optimize RC beams against fire hazards. The DCT application facilitates a deeper understanding of fire-structure interactions and lays the groundwork for practical design tools, thereby potentially enhancing structural safety and efficiency.

这项研究证明了直接耦合技术（DCT）在捕获热与结构响应之间复杂的动态相互作用方面的实用性，特别是当火灾引起显著的几何变化时。DCT在ABAQUS中实现，集成了热分析和结构分析，同时求解温度场和位移场。它结合了关键的材料性能，包括导热系数、比热、密度、应力-应变行为和热膨胀，来模拟RC梁在加热、冷却和火灾后阶段的性能。通过对两束的实验数据进行验证，其中一束在火灾中失效，另一束被评估为剩余容量，该方法证明了高度的准确性。此外，对膨胀涂层钢基板的实验数据进行了验证，以证明DCT能够捕获重大变形问题的热-机械响应，与顺序耦合技术（SCT）模型的127.3%相比，误差为3.4%。详细的参数研究进一步探讨了关键因素，包括混凝土覆盖层、横向刚度和抗压强度，为优化RC梁的火灾隐患提供了见解。DCT的应用有助于加深对火-结构相互作用的理解，并为实际设计工具奠定基础，从而潜在地提高结构的安全性和效率。

{"title":"Structural fire performance of RC beams via direct coupled temperature-displacement nonlinear simulation","authors":"Mohamed Elshorbagi , Mohammad AlHamaydeh , Rafat Siddique","doi":"10.1016/j.firesaf.2025.104630","DOIUrl":"10.1016/j.firesaf.2025.104630","url":null,"abstract":"<div><div>This research demonstrates the utility of the Direct Coupling Technique (DCT) for capturing the intricate, dynamic interplay between thermal and structural responses, particularly when fire induces significant geometric changes. Implemented in ABAQUS, the DCT integrates thermal and structural analyses, solving for temperature and displacement fields simultaneously. It incorporates critical material properties, including thermal conductivity, specific heat, density, stress-strain behavior, and thermal expansion, to model the performance of RC beams across heating, cooling, and post-fire phases. Validated against experimental data from two beams, one that failed during a fire and the other assessed for residual capacity, the approach proves highly accurate. Furthermore, validation of experimental data on an intumescent-coated steel substrate was conducted to demonstrate DCT's ability to capture the thermal-mechanical response for significant deformation problems, with an error of 3.4 % compared to 127.3 % for the Sequential Coupling Technique (SCT) model. A detailed parametric study further explores key factors, including concrete cover, lateral stiffness, and compressive strength, providing insights to optimize RC beams against fire hazards. The DCT application facilitates a deeper understanding of fire-structure interactions and lays the groundwork for practical design tools, thereby potentially enhancing structural safety and efficiency.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"161 ","pages":"Article 104630"},"PeriodicalIF":3.3,"publicationDate":"2025-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145886050","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}

引用次数: 0

Investigation of the impact of diluent addition on radiation, soot volume fraction, and flow dynamics of a buoyant turbulent line fire 稀释剂添加对浮力湍流线火辐射、烟尘体积分数和流动动力学影响的研究

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2025-12-24 DOI: 10.1016/j.firesaf.2025.104627

Sagar Singhal, Pratikash P. Panda

The study of buoyant turbulent diffusion flames requires a detailed understanding of their complex dynamics, including soot formation, radiative heat transfer, and flow field behavior. Accurate prediction of fire radiation and mechanisms of fire suppression demands high-fidelity data across realistic fire scenarios — such as turbulent pool fires and line fires. This work presents a combined experimental and numerical investigation into the effects of

N_{2}

and

{CO}_{2}

dilution on the far-field radiation, soot volume fraction (SVF), and the velocity field of a 15 kW buoyant turbulent line fire. Complementary one-dimensional opposed-flow diffusion flame (1D OFDF) simulations are used to interpret soot formation trends under varying dilution conditions. Planar SVF measurements show that

{CO}_{2}

exerts a significantly stronger soot-inhibiting effect than

N_{2}

. For 20% dilution in the oxidizer stream, the peak mean SVF decreases by 58% with

N_{2}

and by 92% with

{CO}_{2}

. Particle Image Velocimetry (PIV) measurements reveal that

{CO}_{2}

dilution leads to higher peak axial velocities and enhanced flow intermittency — attributed to reduced dissipation and sustained buoyancy-driven motion. Conditional statistics and velocity probability density functions confirm the increased unsteadiness in

{CO}_{2}

-diluted flames. 1D OFDF simulations further indicate that the pronounced soot suppression by

{CO}_{2}

arises from both stronger thermal effects and additional chemical pathways, such as

{CO}_{2} + H \to CO + H_{2}

and

{CO}_{2} + {CH}_{2} \to {CH}_{2} O + CO

. At lower dilution levels (5%–10%), these chemical reactions influence flame kinetics, whereas at higher dilution levels (20%–30%), inert and thermal effects dominate.

浮力湍流扩散火焰的研究需要详细了解其复杂的动力学，包括烟灰形成，辐射传热和流场行为。准确预测火灾辐射和灭火机制需要跨越真实火灾场景的高保真数据，例如湍流池火灾和线火灾。本文结合实验和数值研究了N2和CO2稀释对15kw浮力湍流线火远场辐射、烟尘体积分数（SVF）和速度场的影响。互补一维反流扩散火焰（1D OFDF）模拟用于解释不同稀释条件下烟尘的形成趋势。平面SVF测量结果表明，CO2的抑烟效果明显强于N2。在氧化剂流中稀释20%时，峰值平均SVF在N2中降低58%，在CO2中降低92%。粒子图像测速（PIV）测量显示，二氧化碳稀释导致更高的峰值轴向速度和增强的流动间歇性，这归因于耗散减少和持续的浮力驱动运动。条件统计和速度概率密度函数证实了co2稀释火焰的不稳定性增加。一维OFDF模拟进一步表明，CO2对烟尘的明显抑制来自于更强的热效应和额外的化学途径，如CO2+H→CO+H2和CO2+CH2→CH2O+CO。在较低稀释水平（5%-10%）下，这些化学反应影响火焰动力学，而在较高稀释水平（20%-30%）下，惰性和热效应占主导地位。

{"title":"Investigation of the impact of diluent addition on radiation, soot volume fraction, and flow dynamics of a buoyant turbulent line fire","authors":"Sagar Singhal, Pratikash P. Panda","doi":"10.1016/j.firesaf.2025.104627","DOIUrl":"10.1016/j.firesaf.2025.104627","url":null,"abstract":"<div><div>The study of buoyant turbulent diffusion flames requires a detailed understanding of their complex dynamics, including soot formation, radiative heat transfer, and flow field behavior. Accurate prediction of fire radiation and mechanisms of fire suppression demands high-fidelity data across realistic fire scenarios — such as turbulent pool fires and line fires. This work presents a combined experimental and numerical investigation into the effects of <span><math><msub><mrow><mi>N</mi></mrow><mrow><mn>2</mn></mrow></msub></math></span> and <span><math><msub><mrow><mi>CO</mi></mrow><mrow><mn>2</mn></mrow></msub></math></span> dilution on the far-field radiation, soot volume fraction (SVF), and the velocity field of a 15 kW buoyant turbulent line fire. Complementary one-dimensional opposed-flow diffusion flame (1D OFDF) simulations are used to interpret soot formation trends under varying dilution conditions. Planar SVF measurements show that <span><math><msub><mrow><mi>CO</mi></mrow><mrow><mn>2</mn></mrow></msub></math></span> exerts a significantly stronger soot-inhibiting effect than <span><math><msub><mrow><mi>N</mi></mrow><mrow><mn>2</mn></mrow></msub></math></span>. For 20% dilution in the oxidizer stream, the peak mean SVF decreases by 58% with <span><math><msub><mrow><mi>N</mi></mrow><mrow><mn>2</mn></mrow></msub></math></span> and by 92% with <span><math><msub><mrow><mi>CO</mi></mrow><mrow><mn>2</mn></mrow></msub></math></span>. Particle Image Velocimetry (PIV) measurements reveal that <span><math><msub><mrow><mi>CO</mi></mrow><mrow><mn>2</mn></mrow></msub></math></span> dilution leads to higher peak axial velocities and enhanced flow intermittency — attributed to reduced dissipation and sustained buoyancy-driven motion. Conditional statistics and velocity probability density functions confirm the increased unsteadiness in <span><math><msub><mrow><mi>CO</mi></mrow><mrow><mn>2</mn></mrow></msub></math></span>-diluted flames. 1D OFDF simulations further indicate that the pronounced soot suppression by <span><math><msub><mrow><mi>CO</mi></mrow><mrow><mn>2</mn></mrow></msub></math></span> arises from both stronger thermal effects and additional chemical pathways, such as <span><math><mrow><msub><mrow><mi>CO</mi></mrow><mrow><mn>2</mn></mrow></msub><mo>+</mo><mi>H</mi><mo>→</mo><mi>CO</mi><mo>+</mo><msub><mrow><mi>H</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math></span> and <span><math><mrow><msub><mrow><mi>CO</mi></mrow><mrow><mn>2</mn></mrow></msub><mo>+</mo><msub><mrow><mi>CH</mi></mrow><mrow><mn>2</mn></mrow></msub><mo>→</mo><msub><mrow><mi>CH</mi></mrow><mrow><mn>2</mn></mrow></msub><mi>O</mi><mo>+</mo><mi>CO</mi></mrow></math></span>. At lower dilution levels (5%–10%), these chemical reactions influence flame kinetics, whereas at higher dilution levels (20%–30%), inert and thermal effects dominate.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"160 ","pages":"Article 104627"},"PeriodicalIF":3.3,"publicationDate":"2025-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145840901","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}

引用次数: 0

Fire resistance of concrete columns: Meta-analysis of code-based methods 混凝土柱的耐火性能：基于规范方法的元分析

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2025-12-23 DOI: 10.1016/j.firesaf.2025.104626

Mahadev Rokade, Tim Stratford, Dave Rush

A dataset of 165 fire tests on rectangular concrete columns, spanning five decades, was compiled to evaluate six design methods from five international codes (Eurocode Methods A and B (ECA, ECB), Australian (AS 3600), Chinese (DBJ/T), American (ACI), and Indian (NBC)). A meta-analysis assessed their predictive reliability using historical and recent results. ECA and AS 3600 gave the most consistent and conservative predictions, with ECA performing best overall. For fire resistance ratings (FRR) < 240 min, about 70 % of ECA (2019) predictions were within ±20 % of test outcomes, though accuracy declined at longer durations. AS 3600 produced similar results due to its related formulation. ECB changed notably: 2019 method was unreliable for FRR >140 min, whereas the 2023 version aligned better with recent tests and reduced excessive conservatism. DBJ/T performed adequately on older specimens but overestimated newer ones, while ACI and NBC showed high variability and frequent unconservative predictions. Assessment of the robustness of the ECA (2023) Method with respect to design parameters indicated best performance for 250–300 mm columns, reinforcement ratios of 2.5–3.5 %, effective lengths of 3–5 m, covers of 35–65 mm, and concretes of 20–60 MPa, with reduced accuracy at extreme conditions.

该研究收集了50年来165个矩形混凝土柱的防火测试数据集，以评估来自五个国际规范的六种设计方法(欧洲规范方法A和B （ECA， ECB)，澳大利亚（AS 3600），中国（DBJ/T），美国（ACI）和印度（NBC））。荟萃分析利用历史和最近的结果评估了他们的预测可靠性。ECA和as3600给出了最一致和保守的预测，其中ECA整体表现最好。对于防火等级（FRR） 240分钟，ECA（2019）的预测结果约有70%在测试结果的±20%以内，尽管准确性在较长的持续时间内下降。AS 3600由于其相关的配方也产生了类似的结果。欧洲央行的变化明显：2019年的方法对FRR >；140分钟不可靠，而2023年的版本更符合最近的测试，减少了过度的保守性。DBJ/T在较老样本上表现良好，但对较新样本估计过高，而ACI和NBC则表现出高变异性和频繁的非保守预测。ECA（2023）方法在设计参数方面的稳健性评估表明，最佳性能为250-300毫米柱，配筋率为2.5 - 3.5%，有效长度为3-5米，覆盖层为35-65毫米，混凝土为20-60 MPa，在极端条件下精度降低。

{"title":"Fire resistance of concrete columns: Meta-analysis of code-based methods","authors":"Mahadev Rokade, Tim Stratford, Dave Rush","doi":"10.1016/j.firesaf.2025.104626","DOIUrl":"10.1016/j.firesaf.2025.104626","url":null,"abstract":"<div><div>A dataset of 165 fire tests on rectangular concrete columns, spanning five decades, was compiled to evaluate six design methods from five international codes (Eurocode Methods A and B (ECA, ECB), Australian (AS 3600), Chinese (DBJ/T), American (ACI), and Indian (NBC)). A meta-analysis assessed their predictive reliability using historical and recent results. ECA and AS 3600 gave the most consistent and conservative predictions, with ECA performing best overall. For fire resistance ratings (FRR) < 240 min, about 70 % of ECA (2019) predictions were within ±20 % of test outcomes, though accuracy declined at longer durations. AS 3600 produced similar results due to its related formulation. ECB changed notably: 2019 method was unreliable for FRR >140 min, whereas the 2023 version aligned better with recent tests and reduced excessive conservatism. DBJ/T performed adequately on older specimens but overestimated newer ones, while ACI and NBC showed high variability and frequent unconservative predictions. Assessment of the robustness of the ECA (2023) Method with respect to design parameters indicated best performance for 250–300 mm columns, reinforcement ratios of 2.5–3.5 %, effective lengths of 3–5 m, covers of 35–65 mm, and concretes of 20–60 MPa, with reduced accuracy at extreme conditions.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"161 ","pages":"Article 104626"},"PeriodicalIF":3.3,"publicationDate":"2025-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979380","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}

引用次数: 0

Flame extinction of thermally thick PMMA in Earth gravity versus microgravity: A comparison of Earth and on-orbit space experiments 热厚聚甲基丙烯酸甲酯在地球重力和微重力下的消焰：地球和在轨空间实验的比较

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2025-12-18 DOI: 10.1016/j.firesaf.2025.104625

Christina Liveretou , Jose Rivera , Madeleine Bardy , Carlos Fernandez-Pello , Michael Gollner , Lilly Etzenbach , Maria Thomsen , Sandra Olson , Paul Ferkul

Future spacecraft may operate at sub-atmospheric pressures and elevated oxygen concentrations to reduce preparation time for extra-vehicular activities. It is important to understand fire behavior and the fire risk of materials brought aboard a spacecraft. The limiting oxygen concentration (LOC) is one of the parameters used to determine the flammability of solid fuels. This work aims to compare the LOC for opposed flame spread extinction of polymethyl methacrylate (PMMA) in sub-atmospheric microgravity and Earth-gravity environments. Experiments with cylindrical PMMA samples are conducted in a combustion chamber in the Integrated Combustion Rack (CIR) on the International Space Station (ISS), as well as on laboratory facilities on Earth, at sub-atmospheric pressures with a forced flow of 10 cm/s opposed (counter-current) to the flame spread direction. The oxygen concentration in the chamber decreases naturally at a constant ambient pressure as a result of the PMMA combustion until flame extinction. Results show the LOC in microgravity is lower than at Earth gravity, meaning that flame spread can be sustained at lower oxygen concentrations in reduced buoyancy. The findings confirm that flammability test methods conducted in normal gravity and atmospheric pressure are not conservative enough for the conditions future spacecraft are expected to operate in.

未来的航天器可能在亚大气压力和高氧浓度下运行，以减少舱外活动的准备时间。了解航天器上携带的材料的火灾行为和火灾风险非常重要。极限氧浓度（LOC）是测定固体燃料可燃性的参数之一。本研究的目的是比较聚甲基丙烯酸甲酯（PMMA）在亚大气微重力和地球重力环境下的对向火焰蔓延熄灭的LOC。圆柱形PMMA样品的实验在国际空间站（ISS）的综合燃烧架（CIR）的燃烧室以及地球上的实验室设施中进行，在亚大气压下，与火焰传播方向相反（逆流）的强制流量为10厘米/秒。由于PMMA燃烧直到火焰熄灭，室中的氧浓度在恒定的环境压力下自然降低。结果表明，微重力条件下的LOC比重力条件下的LOC要低，这意味着在较低的氧浓度和较低的浮力条件下，火焰可以持续传播。研究结果证实，在正常重力和大气压下进行的可燃性测试方法对于未来航天器预期的运行条件来说不够保守。

{"title":"Flame extinction of thermally thick PMMA in Earth gravity versus microgravity: A comparison of Earth and on-orbit space experiments","authors":"Christina Liveretou , Jose Rivera , Madeleine Bardy , Carlos Fernandez-Pello , Michael Gollner , Lilly Etzenbach , Maria Thomsen , Sandra Olson , Paul Ferkul","doi":"10.1016/j.firesaf.2025.104625","DOIUrl":"10.1016/j.firesaf.2025.104625","url":null,"abstract":"<div><div>Future spacecraft may operate at sub-atmospheric pressures and elevated oxygen concentrations to reduce preparation time for extra-vehicular activities. It is important to understand fire behavior and the fire risk of materials brought aboard a spacecraft. The limiting oxygen concentration (LOC) is one of the parameters used to determine the flammability of solid fuels. This work aims to compare the LOC for opposed flame spread extinction of polymethyl methacrylate (PMMA) in sub-atmospheric microgravity and Earth-gravity environments. Experiments with cylindrical PMMA samples are conducted in a combustion chamber in the Integrated Combustion Rack (CIR) on the International Space Station (ISS), as well as on laboratory facilities on Earth, at sub-atmospheric pressures with a forced flow of 10 cm/s opposed (counter-current) to the flame spread direction. The oxygen concentration in the chamber decreases naturally at a constant ambient pressure as a result of the PMMA combustion until flame extinction. Results show the LOC in microgravity is lower than at Earth gravity, meaning that flame spread can be sustained at lower oxygen concentrations in reduced buoyancy. The findings confirm that flammability test methods conducted in normal gravity and atmospheric pressure are not conservative enough for the conditions future spacecraft are expected to operate in.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"160 ","pages":"Article 104625"},"PeriodicalIF":3.3,"publicationDate":"2025-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145791249","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}

引用次数: 0

Experimental method for evaluating the heat release rate of external flames in the case of an under-ventilated fire 在不通风火灾情况下评定外火焰放热率的实验方法

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2025-12-17 DOI: 10.1016/j.firesaf.2025.104623

Bouaza Lafdal , Rabah Mehaddi , ElMehdi Koutaiba , Tarek Beji , Pascal Boulet , Gilles Parent , Arnaud Trouvé

A comprehensive set of fifty experimental tests has been carried out to study liquid pool fire dynamics in a naturally-ventilated compartment (dimensions:

0.47 m \times 0.47 m \times 0.84 m

) with a

0.19 m

wide open doorway. The pool diameter varied from 5 to

15 cm

and the ventilation factor,

A H^{1 / 2}

, varied from 0.006 to

0.128 m^{5 / 2}

by varying the door height from 0.10 to

0.77 m

. The well-known fuel-controlled and ventilation-controlled regimes were observed, the latter leading to external flaming. Additionally, extinction occurred for the lowest ventilation factor when the pool diameter varied from 11 to

15 cm

. The HRR inside the compartment was estimated using gas temperature measurements and the well-known MQH correlation. For the scenarios at hand, it is shown that the maximum HRR inside the enclosure is about

900 A H^{1 / 2}

. A novel experimental method was developed to estimate the ‘external’ HRR. The geometry of the external flame was reconstructed using an image processing technique. Then, the view factor from the flame to a radiative heat flux sensor, positioned outside the enclosure, was estimated using a Monte Carlo method. Subsequently, the radiative HRR of the external flame was calculated from the radiative heat flux measurement, the view factor and the area of the sensor. Finally, assuming a specific value for the radiative fraction allowed to obtain the total external HRR from the radiative HRR. The sum of the estimated ‘internal’ and ‘external’ HRR was consistent with the theoretical total HRR from mass loss rate measurements.

在一个0.19m宽开门的自然通风隔间（尺寸：0.47m×0.47m×0.84m）中进行了50项综合实验，研究了液体池火灾动力学。当门高从0.10到0.77m变化时，池直径从5到15cm变化，通风系数ah /2从0.006到0.128m5/2变化。观察到众所周知的燃料控制和通风控制制度，后者导致外部燃烧。另外，当池径在11 ~ 15cm范围内变化时，最低通风系数发生消光。使用气体温度测量和众所周知的MQH相关性来估计隔间内的HRR。对于手头的场景，显示出机箱内的最大HRR约为900ah /2。提出了一种新的实验方法来估计“外部”HRR。利用图像处理技术重建了外火焰的几何形状。然后，使用蒙特卡罗方法估计了火焰到位于外壳外的辐射热通量传感器的视野因子。然后，根据测量的辐射热通量、视因子和传感器的面积计算外火焰的辐射HRR。最后，假设辐射分数的特定值允许从辐射HRR中获得总外部HRR。估计的“内部”和“外部”HRR的总和与质量损失率测量的理论总HRR一致。

{"title":"Experimental method for evaluating the heat release rate of external flames in the case of an under-ventilated fire","authors":"Bouaza Lafdal , Rabah Mehaddi , ElMehdi Koutaiba , Tarek Beji , Pascal Boulet , Gilles Parent , Arnaud Trouvé","doi":"10.1016/j.firesaf.2025.104623","DOIUrl":"10.1016/j.firesaf.2025.104623","url":null,"abstract":"<div><div>A comprehensive set of fifty experimental tests has been carried out to study liquid pool fire dynamics in a naturally-ventilated compartment (dimensions: <span><math><mrow><mn>0</mn><mo>.</mo><mn>47</mn><mtext>m</mtext><mo>×</mo><mn>0</mn><mo>.</mo><mn>47</mn><mtext>m</mtext><mo>×</mo><mn>0</mn><mo>.</mo><mn>84</mn><mtext>m</mtext></mrow></math></span>) with a <span><math><mrow><mn>0</mn><mo>.</mo><mn>19</mn><mtext>m</mtext></mrow></math></span> wide open doorway. The pool diameter varied from 5 to <span><math><mrow><mn>15</mn><mtext>cm</mtext></mrow></math></span> and the ventilation factor, <span><math><mrow><mi>A</mi><msup><mrow><mi>H</mi></mrow><mrow><mn>1</mn><mo>/</mo><mn>2</mn></mrow></msup></mrow></math></span>, varied from 0.006 to <span><math><mrow><mn>0</mn><mo>.</mo><mn>128</mn><msup><mrow><mtext>m</mtext></mrow><mrow><mn>5</mn><mo>/</mo><mn>2</mn></mrow></msup></mrow></math></span> by varying the door height from 0.10 to <span><math><mrow><mn>0</mn><mo>.</mo><mn>77</mn><mtext>m</mtext></mrow></math></span>. The well-known fuel-controlled and ventilation-controlled regimes were observed, the latter leading to external flaming. Additionally, extinction occurred for the lowest ventilation factor when the pool diameter varied from 11 to <span><math><mrow><mn>15</mn><mtext>cm</mtext></mrow></math></span>. The HRR inside the compartment was estimated using gas temperature measurements and the well-known MQH correlation. For the scenarios at hand, it is shown that the maximum HRR inside the enclosure is about <span><math><mrow><mn>900</mn><mi>A</mi><msup><mrow><mi>H</mi></mrow><mrow><mn>1</mn><mo>/</mo><mn>2</mn></mrow></msup></mrow></math></span>. A novel experimental method was developed to estimate the ‘external’ HRR. The geometry of the external flame was reconstructed using an image processing technique. Then, the view factor from the flame to a radiative heat flux sensor, positioned outside the enclosure, was estimated using a Monte Carlo method. Subsequently, the radiative HRR of the external flame was calculated from the radiative heat flux measurement, the view factor and the area of the sensor. Finally, assuming a specific value for the radiative fraction allowed to obtain the total external HRR from the radiative HRR. The sum of the estimated ‘internal’ and ‘external’ HRR was consistent with the theoretical total HRR from mass loss rate measurements.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"160 ","pages":"Article 104623"},"PeriodicalIF":3.3,"publicationDate":"2025-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145840903","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}

引用次数: 0

Impact of linearly increasing heat flux on the ignition of wildland fuels 线性增加的热通量对荒地燃料点火的影响

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2025-12-16 DOI: 10.1016/j.firesaf.2025.104622

Javier Gallardo , Constanza Burgos , Pedro Reszka , Andrés Fuentes , Rodrigo Demarco

An experimental and theoretical study was conducted on the ignition delay time of a forest fuel layer under controlled varying radiative conditions. Experimental data were collected using the Idealized-Firebrand Ignition Test (I-FIT) apparatus, which uses a cylindrical heater to emit a linearly increasing incident heat flux. Data acquisition ensured precise temporal resolution throughout the entire test. The experimental ignition time was then compared to predictions from a theoretical model based on the energy balance of the fuel layer. A simplified analytical solution was obtained for temperature evolution, providing an estimated ignition delay time at different incident heat fluxes. This methodology provides an estimation of the critical heat flux without requiring additional experiments. Special attention was given to the ignition temperature criteria by comparing estimated values with measured quantities. To understand how assumptions affected the simplified analytical solutions, a numerical solution was also compared. The narrow scatter observed confirms the reproducibility of the thoroughly characterized I-FIT apparatus. As the heating rate slope increases, the ignition delay and total energy required decrease. While the model provides useful first-order predictions, it relies on simplifying assumptions whose implications are discussed transparently.

对可控变辐射条件下森林燃料层的点火延迟时间进行了实验和理论研究。实验数据的收集使用理想点火试验（I-FIT）装置，该装置使用圆柱形加热器发射线性增加的入射热流。数据采集确保了整个测试过程中精确的时间分辨率。然后将实验点火时间与基于燃料层能量平衡的理论模型预测的点火时间进行比较。得到了温度演化的简化解析解，给出了不同入射热通量下的点火延迟时间估计。这种方法提供了临界热通量的估计，而不需要额外的实验。通过比较估计值和实测值，特别注意了点火温度标准。为了了解假设如何影响简化解析解，还比较了数值解。观察到的窄散射证实了完全表征的I-FIT装置的再现性。随着升温速率斜率的增大，点火延迟时间和所需总能量减小。虽然该模型提供了有用的一阶预测，但它依赖于简化的假设，其含义被透明地讨论。

{"title":"Impact of linearly increasing heat flux on the ignition of wildland fuels","authors":"Javier Gallardo , Constanza Burgos , Pedro Reszka , Andrés Fuentes , Rodrigo Demarco","doi":"10.1016/j.firesaf.2025.104622","DOIUrl":"10.1016/j.firesaf.2025.104622","url":null,"abstract":"<div><div>An experimental and theoretical study was conducted on the ignition delay time of a forest fuel layer under controlled varying radiative conditions. Experimental data were collected using the Idealized-Firebrand Ignition Test (I-FIT) apparatus, which uses a cylindrical heater to emit a linearly increasing incident heat flux. Data acquisition ensured precise temporal resolution throughout the entire test. The experimental ignition time was then compared to predictions from a theoretical model based on the energy balance of the fuel layer. A simplified analytical solution was obtained for temperature evolution, providing an estimated ignition delay time at different incident heat fluxes. This methodology provides an estimation of the critical heat flux without requiring additional experiments. Special attention was given to the ignition temperature criteria by comparing estimated values with measured quantities. To understand how assumptions affected the simplified analytical solutions, a numerical solution was also compared. The narrow scatter observed confirms the reproducibility of the thoroughly characterized I-FIT apparatus. As the heating rate slope increases, the ignition delay and total energy required decrease. While the model provides useful first-order predictions, it relies on simplifying assumptions whose implications are discussed transparently.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"160 ","pages":"Article 104622"},"PeriodicalIF":3.3,"publicationDate":"2025-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145840902","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}

引用次数: 0