Fire Safety Journal最新文献

Bench-scale thermomechanical assessment of carbon fibre reinforced polymer C-channels 碳纤维增强聚合物 C 型通道的台架规模热力学评估

IF 3.4 3区工程技术

Fire Safety Journal Pub Date : 2024-11-04 DOI: 10.1016/j.firesaf.2024.104285

{"title":"Bench-scale thermomechanical assessment of carbon fibre reinforced polymer C-channels","authors":"","doi":"10.1016/j.firesaf.2024.104285","DOIUrl":"10.1016/j.firesaf.2024.104285","url":null,"abstract":"<div><div>This study investigates the thermomechanical response of carbon fibre reinforced polymer (CFRP) C-channels using a bench-scale apparatus that combines mechanical loading and radiant thermal exposure. The study aims to assess the behaviour of pre-loaded CFRP C-channels, representative of aircraft sub-structures when subjected to fire conditions. Woven prepreg CFRP C-channels were tested under cantilever point load deflection while exposed to varying heat fluxes. Key aspects examined during the study include failure times, displacement, temperature distribution, and failure modes. The findings reveal that heated, pre-loaded C-channels experience distinct phases of physico-chemical decomposition and mechanical degradation. The mechanical degradation includes upward shear buckling of the horizontal flanges and vertical web, along with outward buckling of the vertical web towards the heat source. The study shows that thermal decomposition and mechanical degradation occur simultaneously, influenced by heat flux intensity. Higher heat fluxes accelerate decomposition and reduce load-bearing capacity, while lower fluxes slow degradation. Displacement data indicates that heat flux intensity significantly affects structural response. Temperature measurements show higher fluxes lead to elevated temperatures and steeper gradients, impacting failure times and modes. Increased temperatures correlate with shorter failure times, and variability in failure times decreases as heat flux rises. These insights are significant for understanding the thermomechanical response of C-channels in aircraft sub-structures. The knowledge obtained can contribute to developing more robust and safer aircraft designs, particularly for components exposed to fire conditions, enabling engineers to establish more precise safety margins for CFRP structures, potentially preventing catastrophic failures and thereby enhancing overall aircraft safety.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142592768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Post-fire residual mechanical properties of Q460GJ steel under different pre-tensile stresses 不同预拉伸应力下 Q460GJ 钢的火烧后残余力学性能

IF 3.4 3区工程技术

Fire Safety Journal Pub Date : 2024-10-30 DOI: 10.1016/j.firesaf.2024.104280

{"title":"Post-fire residual mechanical properties of Q460GJ steel under different pre-tensile stresses","authors":"","doi":"10.1016/j.firesaf.2024.104280","DOIUrl":"10.1016/j.firesaf.2024.104280","url":null,"abstract":"<div><div>Previous studies on the post-fire mechanical properties of steel were conducted with unstressed state, without considering the influence of pre-stress which subjected to structures in reality. In this article, the post-fire residual mechanical properties of Q460GJ steel under different pre-tensile stresses were studied. The stress-strain curve, elastic modulus, yield strength, ultimate strength and fracture elongation of Q460GJ steel after different elevated temperatures heating are analyzed in detail. The experimental results are compared with that of Q460 steel and S460 steel in the existing literatures. At last, the predictive equations of post-fire mechanical properties of Q460GJ steel under different pre-tensile stresses are established. Q460GJ steel still maintains good ductility after elevated temperature heating, which increases the possibility of reuse of Q460GJ steel element after fire. The Q460GJ steel has better post-fire ductility than that of Q460 and S460 steels. The predictive equations for the post-fire residual mechanical properties for Q460GJ steel under different pre-tensile stresses were proposed. The variation coefficients of yield strength for Q460GJ steel under different pre-tensile stresses after 20 min different elevated temperatures heating were within 0.065. The findings should have a great significance to providing theoretical support for design of reusing or restoring steel building after fire.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142573533","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

Statistical variation of the burning rate and extinction characteristics of engineered timber products 工程木材产品燃烧率和消光特性的统计变化

IF 3.4 3区工程技术

Fire Safety Journal Pub Date : 2024-10-23 DOI: 10.1016/j.firesaf.2024.104275

{"title":"Statistical variation of the burning rate and extinction characteristics of engineered timber products","authors":"","doi":"10.1016/j.firesaf.2024.104275","DOIUrl":"10.1016/j.firesaf.2024.104275","url":null,"abstract":"<div><div>Understanding the burning rate (mass loss rate, MLR) of timber products is essential in characterizing the ignition characteristics, fire size, and extinction phenomena experienced by timber. Key parameters for timber, such as self-extinction criteria, are presented throughout literature. These parameters are often determined using bench-scale experiments in relatively low trial quantities (e.g., <em>n</em> = 3). This study investigates the influence of trial quantity on the observed statistical variation in key burning rate metrics for timber products (e.g., peak MLR, MLR at extinction). Experiments were performed using a conical heater to conduct 100 repeat trials at incident heat fluxes of 20 kW/m<sup>2</sup>, 40 kW/m<sup>2</sup>, and 50 kW/m<sup>2</sup> on 12.7 mm (0.5 in.) thick ACX cross laminated plywood samples. Significant variability was observed in trials conducted at 40 kW/m<sup>2</sup> due to bimodal behavior where 39% of samples experienced self-extinction and the remaining 61% of samples sustained combustion until burnout (i.e., complete pyrolysis of the material). The MLR at extinction for the trials at 40 kW/m<sup>2</sup> displayed nearly double the magnitude compared to trials conducted at 20 kW/m<sup>2</sup> due to the breakdown of the semi-infinite solid condition. The results from this work illustrate the significance of large trial quantities when investigating complex phenomena.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142592767","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

Performance fire tests on building external walls made of sandwich panels 夹芯板建筑外墙性能防火测试

IF 3.4 3区工程技术

Fire Safety Journal Pub Date : 2024-10-19 DOI: 10.1016/j.firesaf.2024.104273

{"title":"Performance fire tests on building external walls made of sandwich panels","authors":"","doi":"10.1016/j.firesaf.2024.104273","DOIUrl":"10.1016/j.firesaf.2024.104273","url":null,"abstract":"<div><div>External walls are part of the construction system where new solutions appear every day. These systems are usually built with new materials that offer greater thermal resistance but with poor fire behaviour. This fire behaviour can be evaluated in large-scale tests, such as the ones prescribed at BS 8414-1, LEPIR II or ISO-13785-1 standards, that consider a typical scenario where the fire outbreaks inside the building and spreads to outside through a window or venting. However, there are situations in which these systems can be affected by external fires, such as forest fires, goods burning next to the external wall, or even sabotage, that are of interest to be evaluated. This paper presents the results of experimental tests for evaluating the behaviour of building external walls made of sandwich panels, of four different insulation materials in the core (mineral wool, polyisocyanurate - PIR, organic polymer and polyurethane - PUR). The tests were carried out according to BS 8414-2 standard, considering the common internal and a new external fire scenario. The external fire scenario was intended to simulate the case of goods or equipment stored next to the wall, outside the building, that catches fire. The walls' performance was checked according to BRE 135 Annex B criteria. In these tests were registered the temperatures in the exposed and unexposed face of the walls and the incident radiant heat flux in the wall surface. The external fire scenario showed that can be more aggressive to the external wall cladding than the internal fire, demonstrating that this condition must be carefully investigated to propose this situation in standards for the future.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526792","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

On gravity-driven liquid nitrogen jets reach and horizontal spread for extinction of ground fires by aerial means 关于重力驱动液氮喷射器的射程和水平传播，以空中手段扑灭地面火灾

IF 3.4 3区工程技术

Fire Safety Journal Pub Date : 2024-10-19 DOI: 10.1016/j.firesaf.2024.104278

{"title":"On gravity-driven liquid nitrogen jets reach and horizontal spread for extinction of ground fires by aerial means","authors":"","doi":"10.1016/j.firesaf.2024.104278","DOIUrl":"10.1016/j.firesaf.2024.104278","url":null,"abstract":"<div><div>This paper describes experimental and numerical results on the reach and the spread of gravity-driven jets of liquid nitrogen (LN<sub>2</sub>) on the ground for applications to fire extinction by aerial means. A series of experiments released LN<sub>2</sub> jets from different elevations in ambient air to measure their reach and spread distances upon the impingement. A numerical model was developed to simulate the behavior of such jets. Upon validation, the numerical model was used to further predict the LN<sub>2</sub> pool mass and spreading distances under various release configurations. Results showed that the LN<sub>2</sub> survivability is greatly affected by the release height of the cryogen, since the LN<sub>2</sub> quantity reaching the ground decreases as the release height increases. Moreover, releasing larger initial LN<sub>2</sub> quantities and, most importantly using larger nozzle diameters, both the LN<sub>2</sub> pool mass and spreading diameter can be extended. Additional experiments were conducted where cryogen jets were released onto small (∼300 cm<sup>2</sup>) alcohol pool fires; results showed that only limited quantities of the LN<sub>2</sub> evaporated in transit to the fire, and small amounts of the cryogen expediently snuffed the fires. A simplified model also suggested that in fire supression/extinction by LN<sub>2</sub> the fuel cooling mechanism is of secondary importance compared to the mechanism of separating the fuel from oxygen.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526795","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

CFD-based analysis of deviations between thermocouple measurements and local gas temperatures during the cooling phase of compartment fires 基于 CFD 的车厢火灾冷却阶段热电偶测量值与局部气体温度之间的偏差分析

IF 3.4 3区工程技术

Fire Safety Journal Pub Date : 2024-10-17 DOI: 10.1016/j.firesaf.2024.104276

引用次数: 0

Experimental investigation into the effect of transparent fireproof coatings on charring behavior of glued laminated timber exposed to fire 透明防火涂料对暴露于火中的胶合层压木材炭化行为影响的实验研究

IF 3.4 3区工程技术

Fire Safety Journal Pub Date : 2024-10-16 DOI: 10.1016/j.firesaf.2024.104274

{"title":"Experimental investigation into the effect of transparent fireproof coatings on charring behavior of glued laminated timber exposed to fire","authors":"","doi":"10.1016/j.firesaf.2024.104274","DOIUrl":"10.1016/j.firesaf.2024.104274","url":null,"abstract":"<div><div>As timber structures evolve towards greater heights and longer spans for buildings, there is a pressing need to enhance the fire resistance of timber structures. Considering the charring behavior of timber is crucial to the fire resistance of timber structures, it is a promising way to retard the charring behavior of timber and further enhance the fire resistance by applying transparent fireproof coatings. In this study, a series of fire tests were conducted to investigate the effect of transparent fireproof coatings on the charring behavior of Douglas fir glued laminated timber (Glulam) under small-scale ISO 834 standard fire conditions. Different coating types, coating quantities, exposed time to fire and member sizes were considered in the experiments. The experimental results including temperature profiles, maximum temperature, and charring rates for uncoated and coated Glulam specimens were carefully recorded and analyzed. Then, the effect of transparent fireproof coatings was quantified by the proposed ratio of delayed charring. The main mechanism of the delayed charring in fire was finally discussed. This study demonstrated that two transparent fireproof coatings can both effectively lower the temperature at different depths and delay the charring behavior of timber. The reduction in charring rates increased with the increase of coating quantity and decreased as the fire exposure time progressed. The ratio of delayed charring for two coatings can be over 30 % in the initial stage of fire and over 20 % for 1-h standard fire exposure. This study can provide technical support for enhancing the fire resistance of timber structures using transparent coatings.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526793","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

Effect of nano-aluminum hydroxide on the liquid phase properties and fire-fighting foam performance of the mixed surfactants solution 纳米氢氧化铝对混合表面活性剂溶液液相性质和灭火泡沫性能的影响

IF 3.4 3区工程技术

Fire Safety Journal Pub Date : 2024-10-16 DOI: 10.1016/j.firesaf.2024.104277

{"title":"Effect of nano-aluminum hydroxide on the liquid phase properties and fire-fighting foam performance of the mixed surfactants solution","authors":"","doi":"10.1016/j.firesaf.2024.104277","DOIUrl":"10.1016/j.firesaf.2024.104277","url":null,"abstract":"<div><div>Short-chain fluorocarbon surfactants show synergistic effects with hydrocarbon surfactants in foaming and foam stability. Nano-aluminum hydroxide (nano-ATH) was added as an additive to the short-chain fluorocarbon surfactant mixture solution, which was found to increase the surface tension and viscosity of the surfactant mixture solution, and decrease the foaming properties of the solution, as measured by Wilhelmy method, Waring Blender method and viscometer. By measuring zeta potential experiments, surfactant molecules were found to be adsorbed on nano-ATH through charge gravity, which increased the desorption energy of nano-ATH. Measuring the visco-elastic modulus of the solution by rheometer, it was found that nano-ATH increased the visco-elastic modulus of the surfactant mixture solution, which improved the foam's resistance to the external disturbances. Observed by the image analysis system on the foam, the uniform distribution of nano-ATH in the liquid film reduced the coarsening and coalescence speed of foam. Through the self-developed oil resistance test, nano-ATH enhanced the oil resistance stability and inhibition of fuel vapor diffusion of the foam by about 12 %; through self-developed foam fire extinguishing and anti-burning tests, nano-ATH shortened the fire extinguishing time of the two-phase foam by 25 %, and showed better fire extinguishing and anti-burning performance than the foam.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526791","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

Analysis of spatial and design factors for users' acceptance of rescue rooms in road tunnels: An exploratory study using Virtual Reality 分析用户接受公路隧道救援室的空间和设计因素：利用虚拟现实技术进行探索性研究

IF 3.4 3区工程技术

Fire Safety Journal Pub Date : 2024-10-10 DOI: 10.1016/j.firesaf.2024.104272

{"title":"Analysis of spatial and design factors for users' acceptance of rescue rooms in road tunnels: An exploratory study using Virtual Reality","authors":"","doi":"10.1016/j.firesaf.2024.104272","DOIUrl":"10.1016/j.firesaf.2024.104272","url":null,"abstract":"<div><div>In emergency fire situations in road tunnels in which vehicles cannot exit the tunnel, evacuation on foot might be the only alternative. In such scenarios, self-rescue using rescue rooms might provide provisional safe shelter to people trapped in tunnel emergencies. Yet, a stay in a rescue room with unsatisfactory design might contribute to higher levels of distress to the users. The present study examines five different designs of rescue rooms via virtual reality, to study how the different design and spatial factors might affect users' acceptance of such rooms. Thirty-seven people participated in the study, in which both objective (Eye-tracking and heart rate measurement) and subjective data was collected. The results suggest that two factors (i.e. lighting and use of separate areas) increased the feelings of safety and users' acceptance of the rescue rooms. In particular, a container room with blue lighting and separate area for injured people was the favourite among the study participants. The outcomes of this study show that design and spatial factors are crucial if rescue rooms are to be implemented and used in road tunnels.</div></div>","PeriodicalId":50445,"journal":{"name":"Fire Safety Journal","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142446042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A waypoint based approach to visibility in performance based fire safety design 在基于性能的消防安全设计中采用基于航点的能见度方法

IF 3.4 3区工程技术

Fire Safety Journal Pub Date : 2024-10-05 DOI: 10.1016/j.firesaf.2024.104269

引用次数: 0