共查询到19条相似文献,搜索用时 203 毫秒
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为了对地铁车厢内典型地板饰面材料的特性进行全方位的表征和分析,采用锥形量热仪测得了材料燃烧过程中热释放速率、总热释放量、CO 与CO2 释放速率以及总烟释放量等参数。通过热重-红外联用仪使其材料在程序控温条件下进行热解,获得了不同温度下材料热解过程的红外吸收光谱图。使用场发射扫描电镜仪对其材料燃烧完成后残渣的形貌结构进行了表征。实验结果表明:材料在燃烧过程中生成了阻燃炭层结构,在一定时间内起到了隔热、隔氧的作用,延缓了燃烧反应;材料在8 min 内燃烧反应完全,一旦发生火灾,所产生的热危害和烟危害较大;材料热解过程可分为4 个阶段,从350 ℃开始热解,于440 ℃达到热解高峰期,产生大量的H2O、CH4和芳香族化合物。 相似文献
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频发的电动汽车着火事故引起了对离子电池火灾危险性与燃烧特性的关注。以锥形量热仪对常用的几种锂离子电池电解液溶剂的燃烧特性进行了,探讨了不同溶质对其燃烧特性的影响。借助火灾危险综合指数(IFHI)和闪燃特性指数对锂离子电池电解液的火灾危险性进行了评估,发现含LiPF6 溶剂热危险性从大到小依次为:LiPF6 +DMC、LiPF6 +DEC、LiPF6 +EMC、LiPF6 +EC;通过闪燃特性进行评价发现,中等火灾危险等级的有:LiPF6+EC;超高等火灾危险等级的有:LiPF6+DEC、LiPF6+DMC、LiPF6+EMC。 相似文献
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《消防科学与技术》2017,(2)
利用热重—差热同步分析仪研究典型高强玻璃纤维/环氧树脂复合材料在不同升温速率、不同载气气氛影响下的热解特性规律。升温速率取5、10、20、30、40℃/min;气氛取空气及氮气气氛(50 mL/min);实验温度范围为25~800℃。研究表明,随着升温速率的增大,热解反应各阶段起始温度、终止温度、最大失重速率温度均向高温方向移动。空气气氛下,玻纤复合材料热解分为两个阶段,分别是环氧树脂基材热解的两个阶段,玻璃纤维自身不分解;氮气气氛下,玻纤复合材料热解反应一步完成。相同升温速率下,玻纤复合材料与环氧树脂基材的热解初始分解温度、热解温度范围基本一致,玻纤复合材料的热解终止温度及热解各阶段失重速率明显小于环氧树脂基材。运用Kissinger法和Flynn-Wall-Ozawa法进行热解动力学分析,得到玻纤复合材料热解各阶段的表观活化能,两种计算方法所得结果基本一致。热解第二阶段表观活化能明显高于第一阶段,其热稳定性在热解过程中逐渐增强。 相似文献
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利用实验装置模拟潜艇封舱灭火时形成的高压低氧环境,通过改变氧浓度和压力、材料放置角度,对XPS的燃烧特性进行了研究。结果表明,在低氧浓度和高压力的耦合作用下,压力对XPS燃烧特性影响较小,氧体积分数的变化起主导作用,氧体积分数越低,对燃烧的抑制作用越显著;各燃烧特性参数随着放置角度绝对值的增大而增大,负角度时可能产生流淌火。 相似文献
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本文通过运用锥形量热仪横向比较了室内装修材料的点燃时间、热释放速率(HRR)、质量损失速率、发烟量等燃烧特性,并分析其在火灾发生时的危险性,综合实验结果证实,地板和地毯材料的火灾危险性较大。同时提出室内装修材料的研究方向,指出要完善室内装修设计、施工的规范及标准。 相似文献
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在火灾发生发展过程中,可燃装饰材料的热解失重行为极大地影响着室内火灾的发生和蔓延。本文利用TGA851e型热重分析仪对4种装饰材料在不同升温速率(10,15,20℃/min)、空气流速(10,30,50 m L/min)条件下的热解特性进行研究,并找出一般性规律。 相似文献
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《Construction and Building Materials》2007,21(6):1254-1261
The use of thermal insulation materials for building applications is a promising technique but further investigations are needed in this area in order to enhance fire prevention. An experimental study has been carried out to determine toxicity characteristics of commercially manufactured insulation materials, according to UK Naval Engineering standards 713 (NES-713) and colorimetric analysis. Four materials, covering organic foamy and inorganic materials of most of insulation materials used in Taiwan, have been chosen. The various colorimetric gas reaction tubes were used to measure toxic constituents and contents. Toxicity index (TI) was then calculated to evaluate the combustion characteristic of the specimens. The influences of toxic constituents and contents on the toxicity characteristic of testing materials were examined. It was found that significant differences existed between organic foamy and inorganic materials. The results showed that the organic foamy materials, polyethylene foam and polyurethane foam, which did not meet the requirements of the low fire hazard material and were unfavorable in the building’s fire prevention. Finally, it was also observed that the results promote the real knowledge of these insulation materials by using the quantitative analysis to explicate the toxicity chemicals and types and can be important references for fire hazard analysis and developing materials in the future. 相似文献
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模拟聚氯乙烯绝缘阻燃(ZR-BV)单芯铜线在不同电流值时的过电流故障,借助高速摄像、视频截帧等技术,研究导线的发热过程及熔断痕迹形成过程。研究表明:导线发生过电流故障时,I≤3.5Ie,过电流导线仅出现线芯发热,绝缘热解破坏;I≥4Ie,过电流导线会发生熔断,引起绝缘层的燃烧。燃烧发生时,I<4.5Ie,导线绝缘层的燃烧仅能从熔断点蔓延至其两侧一定位置处;I≥4.5Ie,导线绝缘层的燃烧会从导线熔断点处向两侧持续蔓延,直至导线端部。导线的绝缘燃烧是结疤熔痕形成的必要条件,枝晶偏析组织是该熔痕的典型组织。在发生较大电流过电流故障时,导线会出现明火燃烧的现象。 相似文献
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保温墙体是节能建筑的重要组成部分,实现保温与结构一体化是未来节能建筑的发展方向。传统的有机保温材料发泡聚苯乙烯(EPS)与发泡聚氨酯(PU)已被广泛用于墙体保温。随着GB 50016—2014《建筑设计防火规范》对建筑防火等级要求的提高,开发阻燃型的墙体保温材料势在必行。本保温板以3~5 mm和0.5~1 mm 2种粒径的EPS颗粒为主要原材料,经级配设计后作为骨料,以PU作为胶结料,以可膨胀石墨作为阻燃剂,制成阻燃型的复合保温材料芯材;以聚合物水泥砂浆作为面层并以耐碱玻璃纤维方格网作为增强材料制成复合墙体保温板。该保温板可以作为节能建筑外墙、外侧梁柱混凝土施工的模板,经热工分析,复合板材可以达到节能65%以上的总体要求,可以在节能建筑工程中推广使用。 相似文献
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简要分析了高层建筑外墙保温火灾事故的原因.介绍了侨兴QX型不燃保温无机复合新材料,该材料经国家固定灭火系统和耐火构件质量监督检验中心检验,其燃烧性能达到了国标GB8624-2006《建筑材料及制品燃烧性能分级》A1级,即匀质材料不燃烧级标准.并由此展望了高层建筑外墙保温材料的发展前景. 相似文献
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发泡水泥保温板作为一种建筑节能材料,具有A级防火、质轻、高强、耐久性好等优点,但是,又具有脆性大、易破损、施工现场损耗大等缺点,限制了发泡水泥保温板的应用。该文研制了一种纤维增强发泡水泥保温板,将发泡水泥保温板作为芯材,上下表面复合由耐碱玻璃纤维网格布和聚合物砂浆组成的增强层,制成纤维增强发泡水泥保温板,解决了发泡水泥保温板的以上缺点,其相较于普通发泡水泥保温板,抗压强度、抗折强度提高,吸水率降低,使得制品的热工性能更好、规格更大、破损率更低,能够应用在建筑保温、防火隔离带、保温装饰一体化板保温基板等方面,具有广泛的应用前景。 相似文献
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Anne Steen-Hansen Ragni Fjellgaard Mikalsen Ulla Eidissen Jensen 《Fire Technology》2018,54(6):1585-1608
A bench-scale experimental setup has been used to study the conditions necessary for smouldering ignition in four types of loose-fill wood fibre thermal insulation, and to study the development of the smouldering process. The products varied with regard to wood species, grain size and fire retardant chemical additives. The test material was placed in an insulated open top container and heated from below. Temperatures within the sample and mass loss were measured during the tests. Both the fibre size and the level of added fire retardant seem to influence the smouldering ignition. Two different types of smouldering were identified in this study. Materials undergoing smouldering Type 1 obtained maximum temperatures in the range 380°C to 440°C and a total mass loss of 40 wt% to 50 wt%. Materials undergoing smouldering Type 2 obtained maximum temperatures in the range 660°C to 700°C and a total mass loss of 80 wt% to 90 wt%. This implies that Type 2 smouldering involves secondary char oxidation, which represents a risk for transition to flaming combustion and thereby a considerable fire hazard. This has been an exploratory project and the results must therefore be considered as indicative. The findings may, however, have implications for fire safety in the practical use of loose-fill wood fibre insulation in buildings, and further experimental studies should be performed with this in mind to obtain more knowledge about the topic. 相似文献
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Prefabrication of modular residential and office units involves rapid manufacturing various building components off-site from different choices of materials, and transportation to construction site for the complete assembly. While this prefabrication manufacturing process could reduce construction costs, time and waste by using lightweight composite modules (LCM), significant challenge is associated with fire performance of an office modular unit using the modular units. This work aims at investigating the fire performance of a modular office unit using the LCM in terms of heat release rate and temperature history and compared with the traditional office unit model using glazing facade. The heat release and flame propagations in a selected prefabricated modular office unit are simulated with computational fluid dynamic (CFD) taking into account the complexity of the materials systems and the influences of the facade. The numerical procedure combining pyrolysis analysis of the composite sandwiches and the fire dynamic simulation of the combustion process is developed. The computational model is validated with thermal responses obtained from the cone calorimetry experiments. Kinetic parameters obtained from the TGA tests and pyrolysis analysis are used as inputs for the models measuring the fire growth index and total heat release. A multilayer sandwich composite material model is proposed to simulate the thermal responses and combustion processes of the prefabricated unit envelop. Temperatures at critical locations of the units are captured and compared with the standard fire curve to reveal the significant improvement in the fire performance of the office modular unit utilising GFRP composite. 相似文献