某摄影棚防火分区划分的安全性分析

介绍某摄影棚工程概况,针对摄影棚防火分区过大、不适合采用防火墙划分问题,提出摄影棚内设置防火隔离带、消火栓系统、雨淋系统、机械排烟系统、分控制室等措施。设定火灾场景,采用FDS对火灾烟气流动进行模拟分析;设计疏散场景,采用Pathfinder对人员疏散进行模拟分析。对比可用疏散时间与必需疏散时间,验证防火分区划分的可行性。     

某城市广场室内步行街消防设计探讨

针对某室内步行街的建筑特点,分析其防火设计存在的问题,如防火分区、安全疏散等。提出相应的解决方法,如将步行街作为"临时安全区",按一个防火分区设计,并采取一系列措施限制步行街内的火灾烟气蔓延及保证人员疏散的安全等。应用消防性能化设计的方法加以评估,分析其火灾危险性,用计算机模拟程序计算设定火灾场景下的火灾烟气、温度等火灾动力学参数,计算人员疏散情况。     

新疆国际会展中心消防安全性能化评估

针对新建新疆国际会展中心防火分区面积过大、疏散宽度不足、疏散距离过长等设计问题,提出设置防火隔离带、亚安全区等措施的消防设计方案,设计6个火灾场景模拟分析消防设计的安全性.以FDS模拟烟气流动状况,比较可用疏散时间和必需疏散时间.模拟分析结果表明其消防设计能够满足安全性要求.     

重庆奥体中心人员疏散方案分析

介绍体育场馆的建筑特点及火灾危险性,以重庆奥体中心为研究对象,从防火间距、防火分区、防烟分区、消防车道等方面系统分析该场馆的防火设计,并就整体的安全疏散进行分析评估.设置火灾发生在场地中央、二层看台区、一层看台区三个场景模拟火灾烟气,以火灾发生在二层看台区和场地中央模拟人员疏散.结果显示:奥体中心的疏散时间计算略小于体育场疏散设计指南的标准时间,安全疏散存在着一定的危险性,需要从安全管理上采取必要的措施.     

大型室内商业步行街防火分隔技术

以某城市综合体为例,通过设置亚安全区解决防火分区面积过大、疏散距离过长的问题。通过数值模拟和实体火灾试验对大型综合性建筑中的室内商业步行街采用玻璃隔墙替代防火分隔墙的可行性进行研究。设置火灾场景,模拟采用边墙型喷头保护、采用窗式喷头保护、无水喷淋保护时钢化玻璃的耐火表现、破碎时间、隔热性能。火源设定为木垛火与油池火。以实体火灾实验验证数值模拟结果,分析钢化玻璃作为防火分隔的可行性,为具体消防设计和消防行政许可提供一定试验数据和理论支撑。     

兰州中川机场新航站楼性能化防火设计

介绍兰州中川机场新航站楼应用性能化防火设计,解决防火分区面积过大、安全疏散过长等问题。设计10个火灾场景,用EVACNET4软件模拟航站楼各部分人员疏散时间;FDS模拟烟气运动,得到可用疏散时间。经模拟分析,得出各场景下人员均能安全疏散。另外设计2个火灾场景,模拟顶棚及幕墙钢结构的防火安全性。结果显示,在现有的防火安全条件下,火灾不会影响钢结构的安全。建议部分钢结构使用薄型防火涂料进行防火保护。     

关于管廊电缆舱防火分区划分的安全性分析

防火分区的划分可以有效控制烟气的蔓延,也会影响人员疏散和消防扑救,因此本文将防火分区的划分和人员疏散综合考虑。以某综合管廊电缆舱为工程背景,选取防火门关闭自然通风工况为最不利火灾场景,基于性能化防火设计理念,对比不同长度的防火分区对人员疏散的影响。     

高铁枢纽站站房消防设计难点及其解决办法

以长沙南站站房工程为例,针对高铁枢纽站站房防火分区、疏散宽度、疏散距离超出现行规范规定的难题,以性能化消防设计方法,采取合理划分防火分区、设置防火单元控制火灾蔓延、设置"防火舱"限制火灾烟气蔓延扩大、有限引入"燃烧岛"、分阶段引导人员疏散等措施,经安全性评估,确证其消防安全达到了现行规范要求的同等水平。     

火灾疏散研究的热点与前沿 ——基于CNKI数据库的CiteSpace分析

文章通过CiteSpace可视化工具,分析和梳理了近十年来我国火灾疏散研究领域的相关文献,归纳总结了该研究领域文献结构特征、研究热点和研究前沿.结果表明:每年我国火灾疏散研究领域发文量整体较为稳定;研究热点集中在人员密集的公共建筑的防火分区、人员疏散模型的建立以及人员疏散时间的计算等方面;研究前沿为亚安全区的设置方法、复杂功能建筑的防火分区的划分等方面,并且Pathfinder疏散软件在疏散模拟领域受到了越来越多学者的关注.     

某机场航站楼安全疏散设计分析

某新建航站楼体积庞大、人员密集,疏散路径复杂,进行安全疏散设计时,涉及防火分区划分、自动消防设施设置等诸多问题。以所涉及问题为研究目标,设置多个火灾场景,利用性能化设计的方法,对其安全疏散设计的合理性和安全性进行评估。研究中充分考虑设计方案中疏散策略、疏散途径及人员在疏散中的不确定性等因素。结果表明,该航站楼的疏散设计方案是合理的,能实现火灾情况下人员的安全疏散,并提出消防设计及管理的若干对策。     

火灾烟气组分向远距离处迁移速度的差异

利用“房间-走廊”结构的小型实验台进行了火灾烟气向远距离处迁移的实验。结果表明，不同燃料燃烧后烟气迁移速度有较大差别。分析并且证明了烟气体系中烟尘颗粒与产物气体之间存在一定的速度差，为安全防护提出值得注意的问题。     

建筑防烟分区合理挡烟垂壁高度探讨

采用火灾中等发展速度的 t2 模型 ,应用多室区域火灾模拟软件 CFAST 3 .1.6对面积为 5 0 0 m2 和 10 0 0 m2 ,高度为 3 m和 5 m的房间 ,在机械排烟量 3 0 m3/( m2 · h) ,和 60m3/( m2 · h) ,最大热释放速率 0 .5 MW～ 6.0 MW条件下的火灾及烟气发展过程进行了模拟计算。研究结果表明 ,热释放速率 Q≥ 2 .0 MW时 ,绝大部分计算条件下热烟气层厚度大于 0 .5 m,说明目前规范中规定的挡烟垂壁高度 0 .5 m偏小。如果以房间火灾热释放速率 2 .0 MW为限 ,将挡烟垂壁最小高度定义为 2 .0 m是可行的     

防排烟设备选用及控制原理

介绍了防排烟设备的种类、原理、适用场合,重点介绍了防火阀、排烟阀、排烟口、多叶排烟口等设备的功能异同。分析了防排烟阀门与消防控制模块、排烟风机控制箱之间的信号传递关系。根据典型排烟系统的特点,设计了控制原理图。     

单室墙角火壁面烟熏痕迹特征研究

为研究单室墙角火火灾壁面烟熏痕迹特征，采用1/3尺寸火灾试验还原单室墙角火火灾，测定壁面不同点的温度及烟气蔓延速度，研究火源在不同位置时的壁面烟熏痕迹特征；利用PyroSim软件模拟烟气蔓延过程。结果表明：火源位于房间中间时，在屋顶呈现圆形痕迹；火源在墙角时，两边侧墙和墙角顶部形成明显烟熏痕迹；墙角火在墙角位置的温度和烟气蔓延速度高于房间中间起火；试验结果与模拟结果吻合。试验结果可为调查墙角火火灾提供理论及试验依据。     

Estimating Data for Incapacitation of People by Fire Smoke

Fire hazard and risk analyses establish the basis for providing conditions of safety for people, including those that are more sensitive to fire smoke than others. For this purpose, this paper develops a method for estimating, from information on lethal and incapacitating exposures for rats, smoke toxic potency values for incapacitation of smoke-sensitive people. For those engineering applications where the mix of combustibles is unknown, generic values are derived of the concentration of smoke that would incapacitate smoke-sensitive people in 5 min: 6 g/m³ for a well-ventilated fire and 3 g/m³ for an underventilated (e.g., post-flashover) fire. These values are estimated with significant assumptions in their derivation, resulting in an estimated uncertainty of about a factor of two. Further, there is a wide range of smoke toxic potency values reported for various combustibles, and some of these will lead to values significantly higher or lower than these generic figures.     

Evaluation of Toxic Potency Values for Smoke from Products and Materials

Many devices have been used to generate data on the toxic potency of smoke from burning products and materials. This paper critically reviews those apparatus and sorts them by the combustion conditions (related to a type of fire) producing the smoke, the specimens tested, and the animal effect measured. All the usable data were derived using rats, and the toxicological effects encountered were lethality, represented by an LC₅₀value, and incapacitation, expressed as an IC₅₀ value. The data showed a wide range of toxic potency values for the products and materials tested. For those engineering applications where the mix of combustibles is unknown, generic values of smoke toxic potency were derived. Statistical analysis of the wealth of published data yielded a generic LC₅₀value of 30 g/m³ ± 20 g/m³ (one standard deviation) for 30 minute exposure of rats for smoke from well-ventilated combustion. There are limited data for underventilated combustion, and a value of 15 g/m³ ± 5 g/m³ is suggested. The mean value of the ratios of IC₅₀ values to LC₅₀values is 0.50 ± 0.21, consistent with a prior review. Thus, for well-ventilated fires, a generic 30 minute IC₅₀ value (for rats) would be 15 g/m³ ± 10 g/m³; for underventilated fires, the corresponding number would be 7 g/m³ ± 2 g/m³. There are some materials with appreciably lower potency values, indicating higher smoke toxicity. If materials like these are expected to comprise a large fraction of the fuel load, a lower generic value should be used.     

基于卷积神经网络的视频烟雾探测追踪技术研究

火灾探测预警技术是有效降低火灾损失、辅助扑救火灾,保护人民生命财产安全的重要技术保障,是对烟雾进行探测较为有效的手段之一。目前,大部分烟雾探测报警装置主要设置于室内空间场所,仅具备探测和报警功能,同时误报率相对较高,也无法同步传递实时视频画面信息,对室外空间区域也无法进行探测。针对上述情况,基于视频监控系统对烟雾进行实时探测研究。通过对CNN架构进行改进,在EfficientNet中加入残差模块Res-EfficientNet,更精准的探测和识别烟雾。通过STRCF实现对烟雾的精度定位。为提高探测准确率,还考虑了烟雾偏振传输特性,如烟雾的扩散和半透明状态。为了能够更好地探测视频中的烟雾,将空间频率的能量作为滤波器的一维约束项,在基准数据集上进行了试验,试验结果表明,准确率提高了3%。     

Characteristics of Fire Scenarios in Which Sublethal Effects of Smoke are Important

A number of simulations were performed using the CFAST zone fire model to predict the relative times at which smoke inhalation and heat exposure would result in incapacitation. Fires in three building types were modeled: a ranch house, a hotel, and an office building. Gas species yields and rates of heat release for these design fires were derived from a review of real-scale fire test data. The incapacitation equations were taken from draft 14 of ISO document 13571. Sublethal effects of smoke were deemed important when incapacitation from smoke inhalation occurred before harm from thermal effects occurred. Real-scale HCl yield data were incorporated as available; the modeling indicated that the yield would need to be 5 to 10 times higher for incapacitation from HCl to precede incapacitation from narcotic gases, including CO CO₂, HCN and reduce O₂.The results suggest that occupancies in which sublethal effects from open fires could affect escape and survival include multi-room residences, medical facilities, schools, and correctional facilities. In addition, fires originating in concealed spaces in any occupancy pose such a threat. Sublethal effects of smoke are not likely to be of prime concern for open fires in single- or two-compartment occupancies (e.g., small apartments and transportation vehicles) themselves, although sublethal effects may be important in adjacent spaces; buildings with high ceilings and large rooms (e.g., warehouses, mercantile); and occupancies in which fires will be detected promptly and from which escape or rescue will occur within a few minutes.     

商业建筑排烟口与挡烟垂壁组合控制烟气

利用尺寸为38m(长)×21m(宽)×5.4m(高)的真实商业建筑火灾场景,使用3.0 MW真实柴油池火火源,研究排烟口与挡烟垂壁组合控制烟气时挡烟垂壁高度、排烟口位置和朝向等因素对烟气控制效果的影响。在火灾规模、排烟量和排烟系统启动时间都一定的情况下,挡烟垂壁的高度是影响烟气控制效果的关键因素。排烟口距火源越近烟气控制效果越好。排烟口的朝向对烟气控制效果的影响并不显著。