Pub Date : 2026-06-01Epub Date: 2025-12-30DOI: 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.
{"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":"2026-06-01","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}
Pub Date : 2026-06-01Epub Date: 2026-01-28DOI: 10.1016/j.firesaf.2026.104643
M. Kamalvand , J.W. Maclean , L. Bisby , P. Bamonte
Current design guidelines for structural fire safety generally focus on the resistance of structural members for a specified period under uniform heating in a standardized, harmonised fire scenario. A potential shortcoming of this method is that it neglects the impact of non-uniform thermal loading, as well as the behaviour of structural members in the cooling phase of the fire. In this paper, a nonlinear finite element model has been developed to evaluate the behaviour of reinforced concrete columns with square cross sections under non-uniform thermal loading applied locally on one face. The numerical simulations have been performed in two steps: a heat transfer analysis followed by an evaluation of the structural behaviour of the axially loaded columns exposed to the heat flux. Due to the importance of second-order effects, axial loads with different eccentricities were considered, together with a user-defined subroutine developed to implement the irreversible concrete damage during cooling. Comparing the numerical results with the experimental data suggests that the proposed model is capable of reasonably predicting the thermal history at different locations within the column cross-section, and the history of mid-height lateral deflection of the columns during heating and cooling. It was observed that the column response is strongly influenced by the initial eccentricity of the load, and that its response when heated on the face subjected to higher compression stresses is drastically different from the response when heating takes place on the face with lower compression stresses. The columns loaded to 60% of their ambient temperature capacity and heated on the face subjected to higher compressive stresses exhibited lateral deflections during cooling up to 2.5 times the deflections at the end of the heating phase or even failed in cooling after a few hours. The analyses presented demonstrate the complexity of the structural response of concrete columns under non-uniform heating. Such complexity, which is not captured by conventional methods of assessing fire resistance, validates advanced numerical modelling techniques to predict structural response under more complex (and potentially realistic) conditions.
{"title":"Evaluation of reinforced concrete columns resistance with eccentric loading under non-uniform heating regimes","authors":"M. Kamalvand , J.W. Maclean , L. Bisby , P. Bamonte","doi":"10.1016/j.firesaf.2026.104643","DOIUrl":"10.1016/j.firesaf.2026.104643","url":null,"abstract":"<div><div>Current design guidelines for structural fire safety generally focus on the resistance of structural members for a specified period under uniform heating in a standardized, harmonised fire scenario. A potential shortcoming of this method is that it neglects the impact of non-uniform thermal loading, as well as the behaviour of structural members in the cooling phase of the fire. In this paper, a nonlinear finite element model has been developed to evaluate the behaviour of reinforced concrete columns with square cross sections under non-uniform thermal loading applied locally on one face. The numerical simulations have been performed in two steps: a heat transfer analysis followed by an evaluation of the structural behaviour of the axially loaded columns exposed to the heat flux. Due to the importance of second-order effects, axial loads with different eccentricities were considered, together with a user-defined subroutine developed to implement the irreversible concrete damage during cooling. Comparing the numerical results with the experimental data suggests that the proposed model is capable of reasonably predicting the thermal history at different locations within the column cross-section, and the history of mid-height lateral deflection of the columns during heating and cooling. It was observed that the column response is strongly influenced by the initial eccentricity of the load, and that its response when heated on the face subjected to higher compression stresses is drastically different from the response when heating takes place on the face with lower compression stresses. The columns loaded to 60% of their ambient temperature capacity and heated on the face subjected to higher compressive stresses exhibited lateral deflections during cooling up to 2.5 times the deflections at the end of the heating phase or even failed in cooling after a few hours. The analyses presented demonstrate the complexity of the structural response of concrete columns under non-uniform heating. Such complexity, which is not captured by conventional methods of assessing fire resistance, validates advanced numerical modelling techniques to predict structural response under more complex (and potentially realistic) conditions.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"161 ","pages":"Article 104643"},"PeriodicalIF":3.3,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146189450","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}
Pub Date : 2026-06-01Epub Date: 2026-01-09DOI: 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.
{"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":"2026-06-01","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}
Pub Date : 2026-06-01Epub Date: 2026-02-02DOI: 10.1016/j.firesaf.2026.104652
Sébastien Dubourg , Thibaut Rochard , Daniel Marteau , David Brun-Buisson , Magali Reytier , Rémi Vincent , Alain Bengaouer
The use of lithium-ion (Li-ion) batteries has rapidly increased due to improvements in performance, durability, and cost-effectiveness, driven by the growth of electric vehicles (EVs), renewable energy storage, and portable electronics. However, the safety of Lithium-ion batteries remains a major concern due to the risk of thermal runaway, which can result in fast heat release, the ejection of particles and gases, and possibly fire and explosion. Therefore, the reliable characterization of thermal runaway energy and gas volume release is essential. In this study, 29 thermal runaway tests of large-capacity prismatic and pouch NMC (Nickel Manganese Cobalt oxide cathode) cells were analysed. Thermal runaway energy, normalized by the electrical energy of the cell at the time thermal runaway occurs, was constant and equal to 1.25 during all the tests performed under vacuum and inert atmosphere. Similarly, the normalized number of moles generated during thermal runaway remained constant at 4.9 × 10−3 mol kJ−1. When the tests were conducted in air, the large quantity of oxygen available led to additional combustion and energy release. The normalized thermal runaway energy increased to 5.0, while the normalized average number of moles decreased to 4.2 × 10−3 mol kJ−1. Thermodynamic equilibrium calculations of vented gas combustion with air show that gas phase combustion alone does not explain this energy increase, the contribution of graphite is therefore demonstrated. The two conditions-under vacuum and in air-represent the two limiting cases of air access in a typical battery module, therefore the data presented in this work can be useful for evaluating thermal runaway propagation and casing integrity in a battery module during the design phase.
{"title":"Unveiling the relationship between the energy and gas released during the thermal runaway of Li-ion cells and their stored electrical energy","authors":"Sébastien Dubourg , Thibaut Rochard , Daniel Marteau , David Brun-Buisson , Magali Reytier , Rémi Vincent , Alain Bengaouer","doi":"10.1016/j.firesaf.2026.104652","DOIUrl":"10.1016/j.firesaf.2026.104652","url":null,"abstract":"<div><div>The use of lithium-ion (Li-ion) batteries has rapidly increased due to improvements in performance, durability, and cost-effectiveness, driven by the growth of electric vehicles (EVs), renewable energy storage, and portable electronics. However, the safety of Lithium-ion batteries remains a major concern due to the risk of thermal runaway, which can result in fast heat release, the ejection of particles and gases, and possibly fire and explosion. Therefore, the reliable characterization of thermal runaway energy and gas volume release is essential. In this study, 29 thermal runaway tests of large-capacity prismatic and pouch NMC (Nickel Manganese Cobalt oxide cathode) cells were analysed. Thermal runaway energy, normalized by the electrical energy of the cell at the time thermal runaway occurs, was constant and equal to 1.25 during all the tests performed under vacuum and inert atmosphere. Similarly, the normalized number of moles generated during thermal runaway remained constant at 4.9 × 10<sup>−3</sup> mol kJ<sup>−1</sup>. When the tests were conducted in air, the large quantity of oxygen available led to additional combustion and energy release. The normalized thermal runaway energy increased to 5.0, while the normalized average number of moles decreased to 4.2 × 10<sup>−3</sup> mol kJ<sup>−1</sup>. Thermodynamic equilibrium calculations of vented gas combustion with air show that gas phase combustion alone does not explain this energy increase, the contribution of graphite is therefore demonstrated. The two conditions-under vacuum and in air-represent the two limiting cases of air access in a typical battery module, therefore the data presented in this work can be useful for evaluating thermal runaway propagation and casing integrity in a battery module during the design phase.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"161 ","pages":"Article 104652"},"PeriodicalIF":3.3,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146189454","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}
Pub Date : 2026-06-01Epub Date: 2026-02-04DOI: 10.1016/j.firesaf.2026.104654
Pengzhi Wu , Zhenmin Luo , Hu Wen , Changchun Liu , Xinyue Ji , Litao Liu
The geometry and size of hydrogen-blended natural gas (HBNG) jet flames are key parameters that determine their potential to trigger a series of accidental events, such as domino effects. This study experimentally investigated HBNG jet flames with hydrogen ratios of 0∼30%, inclination angles of −30° to 30°, and volume flow rates of 10∼40 L/min. A MATLAB code was used to extract the trajectory, projection distance, flame envelope boundary (side view), and flame widths of 50% intermittency flame. The results show that the flame-envelope boundary, horizontal projection distance, vertical projection distance, maximum flame width, and trajectory length decrease with increasing hydrogen blending ratio. As the jet inclination angle varies from negative to positive, the curvature of the flame trajectory gradually decreases, whereas the flame trajectory length increases. The effect of volume flow rate on the vertical projection distance becomes more pronounced at larger positive or negative inclination angles. Furthermore, a predictive method was established to determine the trajectory and envelope boundary of inclined HBNG jet flames. The flame trajectory was obtained by solving an integral model, the flame length was obtained by a correlation based on the flame Froude number, and the flame envelope boundary was calculated using a two-stage approach.
{"title":"Experimental and modeling study on the geometric characteristics of inclined hydrogen-blending natural gas jet flames","authors":"Pengzhi Wu , Zhenmin Luo , Hu Wen , Changchun Liu , Xinyue Ji , Litao Liu","doi":"10.1016/j.firesaf.2026.104654","DOIUrl":"10.1016/j.firesaf.2026.104654","url":null,"abstract":"<div><div>The geometry and size of hydrogen-blended natural gas (HBNG) jet flames are key parameters that determine their potential to trigger a series of accidental events, such as domino effects. This study experimentally investigated HBNG jet flames with hydrogen ratios of 0∼30%, inclination angles of −30° to 30°, and volume flow rates of 10∼40 L/min. A MATLAB code was used to extract the trajectory, projection distance, flame envelope boundary (side view), and flame widths of 50% intermittency flame. The results show that the flame-envelope boundary, horizontal projection distance, vertical projection distance, maximum flame width, and trajectory length decrease with increasing hydrogen blending ratio. As the jet inclination angle varies from negative to positive, the curvature of the flame trajectory gradually decreases, whereas the flame trajectory length increases. The effect of volume flow rate on the vertical projection distance becomes more pronounced at larger positive or negative inclination angles. Furthermore, a predictive method was established to determine the trajectory and envelope boundary of inclined HBNG jet flames. The flame trajectory was obtained by solving an integral model, the flame length was obtained by a correlation based on the flame Froude number, and the flame envelope boundary was calculated using a two-stage approach.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"161 ","pages":"Article 104654"},"PeriodicalIF":3.3,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146189449","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}
False alarms erode public confidence in fire-safety systems and often lead occupants to disable smoke detectors, compromising life-safety margins. This study quantifies the false-alarm susceptibility of five newly manufactured spot-type photoelectric detectors, including conventional, analog-addressable, and multi-sensor, exposed to realistic nuisance stimuli (steam, dust, cigarette smoke, insect ingress) and four EN 54-7 fire scenarios (TF2–TF5). All devices were vulnerable to saturated steam and airborne dust, while spider webs generated non-resettable alarms in every unit. Cigarette smoke produced transient optical-density peaks that misled detectors lacking signal-integration algorithms. In full-scale fire trials, conventional detectors responded to smoldering wood and cotton but failed to alarm for flaming polyurethane or n-heptane. By contrast, the multi-sensor unit achieved rapid fire recognition and exhibited the greatest immunity to environmental nuisances. The results identify spider webs and persistent steam as dominant false-alarm drivers and expose detection blind spots for fast-growing plastic and liquid fires. Based on the findings, it is recommended that Taiwan's type-approval scheme incorporate real-fire scenarios (smoldering and flaming) and emphasize proper installation and six-monthly cleaning to cut both false and missed alarms and enhance public safety.
{"title":"False-alarm susceptibility of spot-type smoke detectors under realistic fire and nuisance conditions","authors":"Chia-Lung Wu , Chei-Fei Hung , Kang Chao , Hsiao-Chun Huang , Tien-Fu Yu , Yu-Tang Wen , Ming-Mou Hung","doi":"10.1016/j.firesaf.2025.104621","DOIUrl":"10.1016/j.firesaf.2025.104621","url":null,"abstract":"<div><div>False alarms erode public confidence in fire-safety systems and often lead occupants to disable smoke detectors, compromising life-safety margins. This study quantifies the false-alarm susceptibility of five newly manufactured spot-type photoelectric detectors, including conventional, analog-addressable, and multi-sensor, exposed to realistic nuisance stimuli (steam, dust, cigarette smoke, insect ingress) and four EN 54-7 fire scenarios (TF2–TF5). All devices were vulnerable to saturated steam and airborne dust, while spider webs generated non-resettable alarms in every unit. Cigarette smoke produced transient optical-density peaks that misled detectors lacking signal-integration algorithms. In full-scale fire trials, conventional detectors responded to smoldering wood and cotton but failed to alarm for flaming polyurethane or n-heptane. By contrast, the multi-sensor unit achieved rapid fire recognition and exhibited the greatest immunity to environmental nuisances. The results identify spider webs and persistent steam as dominant false-alarm drivers and expose detection blind spots for fast-growing plastic and liquid fires. Based on the findings, it is recommended that Taiwan's type-approval scheme incorporate real-fire scenarios (smoldering and flaming) and emphasize proper installation and six-monthly cleaning to cut both false and missed alarms and enhance public safety.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"161 ","pages":"Article 104621"},"PeriodicalIF":3.3,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145928146","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}
The structural stability of steel frames under fire conditions is profoundly influenced by connection behavior. While most existing studies neglect time-dependent creep, this work explicitly models thermal creep and cooling effects using validated constitutive laws for ASTM A36 and A992 steels, and proposes a framework for assessing the thermal response of bolted end-plate connections. Two thermal loading scenarios were considered: uniform heating and heat transfer based on the ISO 834 fire curve. Realistic temperature distributions improved analytical accuracy. The numerical model was validated against experimental data for end-plate and shear-plate connections. A parametric study evaluated effects of steel grade, heating/cooling rates, initial cooling temperature, and cooling duration.
Results
show that thermal creep increases deflections, reduces compressive forces in beams, and shifts the load-bearing mechanism from bending to axial action during cooling. The beam's tensile force depends on heating rate and initial cooling temperature. A notable opening between the end-plate and column flange occurred during cooling, intensified by slower heating and higher initial cooling temperatures. These findings highlight the importance of modeling time-dependent thermal effects for reliable design of steel connections under fire.
{"title":"Thermal-creep and cooling effects on fire response of bolted end-plate steel connections","authors":"Maziar Barzegar, Alireza Mirzagoltabar Roshan, Hossein Yousefpour","doi":"10.1016/j.firesaf.2026.104641","DOIUrl":"10.1016/j.firesaf.2026.104641","url":null,"abstract":"<div><div>The structural stability of steel frames under fire conditions is profoundly influenced by connection behavior. While most existing studies neglect time-dependent creep, this work explicitly models thermal creep and cooling effects using validated constitutive laws for ASTM A36 and A992 steels, and proposes a framework for assessing the thermal response of bolted end-plate connections. Two thermal loading scenarios were considered: uniform heating and heat transfer based on the ISO 834 fire curve. Realistic temperature distributions improved analytical accuracy. The numerical model was validated against experimental data for end-plate and shear-plate connections. A parametric study evaluated effects of steel grade, heating/cooling rates, initial cooling temperature, and cooling duration.</div></div><div><h3>Results</h3><div>show that thermal creep increases deflections, reduces compressive forces in beams, and shifts the load-bearing mechanism from bending to axial action during cooling. The beam's tensile force depends on heating rate and initial cooling temperature. A notable opening between the end-plate and column flange occurred during cooling, intensified by slower heating and higher initial cooling temperatures. These findings highlight the importance of modeling time-dependent thermal effects for reliable design of steel connections under fire.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"161 ","pages":"Article 104641"},"PeriodicalIF":3.3,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146189451","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}
Pub Date : 2026-06-01Epub Date: 2025-12-30DOI: 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.
{"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":"2026-06-01","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}
Pub Date : 2026-06-01Epub Date: 2026-01-23DOI: 10.1016/j.firesaf.2026.104644
Takuya Yamazaki , Daiki Matsugi , Yuji Nakamura
This study investigates the relationship between mixing ratio and smoldering behavior in wood–polypropylene (PP) mixtures. Test samples were prepared by varying the proportion of wood to PP powder. Burning tests revealed that the smoldering rate decreased almost linearly with increasing PP content up to 40wt%, beyond which smoldering combustion was no longer sustained. Thermal analysis indicated a co-pyrolysis effect, characterized by enhanced heating value and altered reaction kinetics in the mixtures. A heat balance model was applied to evaluate the influence of PP addition on smoldering rate with and without co-pyrolysis. When co-pyrolysis was considered, the estimated smoldering rate increased with PP content compared to the case without co-pyrolysis, highlighting its significant role in smoldering combustion. These findings provide critical insights for fire safety risk assessment of wood/plastic composites and landfill fires.
{"title":"Effect of mixing ratio on smoldering rate for wood-plastic mixture materials","authors":"Takuya Yamazaki , Daiki Matsugi , Yuji Nakamura","doi":"10.1016/j.firesaf.2026.104644","DOIUrl":"10.1016/j.firesaf.2026.104644","url":null,"abstract":"<div><div>This study investigates the relationship between mixing ratio and smoldering behavior in wood–polypropylene (PP) mixtures. Test samples were prepared by varying the proportion of wood to PP powder. Burning tests revealed that the smoldering rate decreased almost linearly with increasing PP content up to 40wt%, beyond which smoldering combustion was no longer sustained. Thermal analysis indicated a co-pyrolysis effect, characterized by enhanced heating value and altered reaction kinetics in the mixtures. A heat balance model was applied to evaluate the influence of PP addition on smoldering rate with and without co-pyrolysis. When co-pyrolysis was considered, the estimated smoldering rate increased with PP content compared to the case without co-pyrolysis, highlighting its significant role in smoldering combustion. These findings provide critical insights for fire safety risk assessment of wood/plastic composites and landfill fires.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"161 ","pages":"Article 104644"},"PeriodicalIF":3.3,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146078441","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}
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.
{"title":"Characteristics of water film flow on a vertical glass surface and its control of temperature rise in the glass","authors":"Shuo Zhang, Shuhei Sonobe, Yu-hsiang Wang, Yoshifumi Ohmiya","doi":"10.1016/j.firesaf.2025.104632","DOIUrl":"10.1016/j.firesaf.2025.104632","url":null,"abstract":"<div><div>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.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":"161 ","pages":"Article 104632"},"PeriodicalIF":3.3,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145928144","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}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号