垂直与水平防火防烟分区的提法和建议

充分认识建筑物防火、防烟分区在垂直方向上的重要性,提出垂直防火、防烟分区和水平防火、防烟分区的提法和划分原则,分析垂直防火、防烟分区的主要内容和一些相关措施。     

高层民用建筑要注意防烟排烟设计

火灾发生时如何及时排除烟气,保障高层民用建筑内部人员的安全疏散和有利于扑救火灾,正确合理地设计防烟、排烟设施起着重要作用。一、防烟分区的合理划分防烟分区主要用挡烟垂壁或档烟梁等设施来划分,目的在于防止烟气扩散,满足火灾时人员的安全疏散及扑救需要。（一）防烟分区不得跨越防火分区且面积不宜过大。如果防烟分区跨越了防火分区,则形成防火分区的防火门、防火卷帘、防火阀必须具有隔烟性能,而且要与感烟报警系统联锁,而实际上这些设备难以达到此要求。从实际排烟效果看,防烟分区面积划分得越小则排烟效果越好。然而,在…     

Z值及防烟分区对高大空间排烟系统的影响分析

分析了空间净高大于9 m的空间燃料面到烟层底部的高度即Z值对排烟量的影响,比较了净高大于9 m且单个防火分区超过2 000 m2的高大空间不划分防烟分区和划分防烟分区排烟系统的差异,提出了对于这类空间机械排烟系统的建议。     

地下汽车库的排风与排烟系统设计

介绍了地下汽车库的排风与排烟系统设计,包括防烟防火分区的划分、排烟排风系统的设计以及消防补风系统。     

中庭式地铁车站火灾烟气流动研究

介绍中庭式地铁车站火灾烟气控制方法。根据相似三定律,以某中庭式地铁车站为原型建立1∶15的缩尺模型。根据工程要求划分防烟分区。分别在模型的站台防烟分区1、站台防烟分区2、站厅防烟分区1以及中庭区做无通风系统和机械排烟试验,得到温度分布、烟气层高度等结果,分析烟气流动情况。根据分析结果,建议在站台与中庭的交界处设置防火卷帘,并且增大站台防烟风区的风量。在站台层列车隧道的屏蔽门采用全封闭式,防止烟气通过列车隧道在站台层向相邻站台区域蔓延。中庭顶部分成两个防烟分区进行排烟。     

关于地下车库防排烟系统中防烟分区界的探讨

在实际的工作中遇到了有关地下车库防排烟的问题,对现行的地下车库设计规范中的条文进行探讨,提出地下车库在实际的设计中对防烟分区界划分的疑问。针对地下车库一个面积不超过4 000 m~2的防火分区的防排烟设计,为更好的实现排烟效果和简化控制,提出取消防烟分区界的划分的建议。     

对大面积房间排烟系统设计的几点认识

论述了大面积房间排烟系统设计中划分防烟分区的重要性和依据，提出了加大排烟量、整个防火分区全面排烟的观点，对排风兼排烟系统的设置与转换进行了分析。     

关于地下建筑排烟设计的几点分析

近些年来地下建筑发展很快 ,特别是一批大型超市 ,每层建筑面积近万平方米 ,营业时间客流量大 ,一旦有火情 ,人员疏散需要一段时间 ,而火场烟气的蔓延将给人员和灭火救援带来极大的困难 ,因此有效排除烟气、阻止烟气扩散的消防设计是十分必要的。笔者对地下建筑的排烟设计谈几点意见。1　防烟分区划分无吊顶的地下建筑可利用梁进行防烟分区划分 ,但梁间距不同 ,组合成的防烟分区面积也不一样 ,因此必须在防火分区设计的基础上沿梁用粗虚线明确每个防烟分区 ,然后再布置管道和排烟口。地下建筑楼板下管路密布 ,考虑装饰美观 ,一些建筑采用了…     

超大型电子洁净厂房防排烟系统设计

超大型电子洁净厂房工艺设备体积大、自动化程度高且生产过程连续,其洁净室面积过大,厂房防火分区划分需要参照电子行业规范作为设置依据。以某洁净厂房为例,介绍了人员疏散用的防烟楼梯间的设置方法、防烟分区划分及防排烟系统设置等,对比了新旧规范防排烟系统设置的区别。结合GB 51251—2017《建筑防烟排烟系统技术标准》,对工厂建设过程中的防排烟设置要点进行了探讨。     

商业建筑的消防性能化设计

介绍了消防性能化设计在商业建筑的应用。针对以防火玻璃或者钢化玻璃加喷淋保护进行商铺与中庭分隔的方式,提出了以中庭作为"准安全区"的消防策略。提出了人员荷载的确定方法和借用其他防火分区疏散的限制条件。提出了烟控系统设计的原则、方法和案例,包括防烟分区划分、挡烟垂壁高度的确定、排烟量的确定、每个防烟分区排烟口数量的确定、吊顶形式对排烟的影响和补风对排烟的影响。     

Effectiveness of downward evacuation in a large-scale subway fire using Fire Dynamics Simulator

Effective evacuation routes in the case of a large-scale subway fire were studied. A serious problem in the subway fire is that the directions of smoke flow are coincident with those of evacuation toward the surface. Hence, it is necessary to design an evacuation route without interference from smoke. A disastrous fire broke out in the Jungangno subway station in Daegu, South Korea in 2003. Based on this case, the Jungangno subway station with three basement levels was used in Fire Dynamics Simulator model in this study. The influences of smoke, temperature, and toxic gases (carbon monoxide [CO] and carbon dioxide [CO₂]) were computed at the evacuation staircases in the subway station with a fire source in the third basement floor (B3). The calculations showed that the evacuation staircases had high smoke density, temperature, and concentrations of CO and CO₂ in the subway fire. Hence, these factors greatly affected all of the upward evacuation staircases due to the coincidence of the smoke flow and the evacuation routes. Therefore, our paper proposes a new subway station with a fourth basement floor (B4) having downward evacuation routes which are in the opposite direction to the smoke flow. The results of analysis show that these factors hardly affected the staircases from B3 to B4. We conclude that downward evacuation can be more effective than upward evacuation for a large-scale subway fire.     

关于防烟楼梯前室室内消火栓设置的讨论

通过实际工程中遇到有关室内消火栓设置位置的问题,从相关规范要求、防烟楼梯前室的排烟方式以及室内消火栓系统的实际操作和使用几方面,对防烟楼梯前室设置室内消火栓的可行性及合理性提出个人的观点和看法.     

机械排烟与水喷淋对仓室火灾控制效果的实验研究

研究了大空间建筑中仓室消防措施的有效性，按照规范设计的工况设计了全尺寸实验，研究了机械排烟和水喷淋对烟气层温度及高度的控制效果，并将结果与消防措施实效的情况下相比较，说明按照规范设计的消防措施能够有效的控制火灾，在规范设计基础上增大风机排烟量和水喷淋压力，取得了更加良好的效果，达到了灭火的目的。     

高层民用建筑防排烟设计常见问题分析

提出和分析了防排烟设计审查中发现的一些问题，包括加压送风(排烟)量的确定、加压送风系统余压阀和止回阀的设置、加压送风机房新风进风通路的设置、地上地下共用(防烟)楼梯间时加压送风系统的设置、宜设机械排烟设施的几种特殊情况、采用自然排烟建筑高度及开窗型式和面积的限制、排烟防火阀的设置及加压送风口和排烟口风速的控制等，给出了相应的解决建议。     

福州海峡国际会展中心性能化防火设计与分析

针对福州国际会展中心开幕大厅中庭防火分区面积过大的问题,提出了"亚安全区"、"避难走道"等性能化设计,保证消防安全。设计10个火灾场景,以SIMULEX软件模拟会展中心各部分人员疏散时间;以FDS模拟烟气运动,得到可用疏散时间。经模拟分析,各场景下均能安全疏散。设计2个场景模拟顶棚及幕墙钢结构的防火安全性。结果显示,在现有防火安全条件下,火灾不会影响钢结构的安全。建议顶棚部分钢结构使用薄型防火涂料进行防火保护。     

Experimental study of natural roof ventilation in full-scale enclosure fire tests in a small compartment

An analysis of full-scale fire test experimental data is presented for a small compartment (3×3.6×2.3 m). A square steady fire source is placed in the center of the compartment. There is an open door and a horizontal opening in the roof, so that natural ventilation is established for the well-ventilated fire. A parameter study is performed, covering a range of total fire heat release rates (330, 440 and 550 kW), fire source areas (0.3×0.3 m and 0.6×0.6 m) and roof ventilation opening areas (1.45×1 m, 0.75×1 m and 0.5×1 m). The impact of the different parameters is examined on the smoke layer depth and the temperature variations in vertical direction in the compartment. Both mean temperatures and temperature fluctuations are reported. The total fire heat release rate value has the strongest influence on the hot smoke layer average temperature rise, while the influence of the fire source area and the roof opening is smaller. The hot smoke layer depth, determined from the measured temperature profiles, is primarily influenced by the fire source area, while the total fire heat release rate and the roof opening only have a small impact. Correlations are given for the hot smoke layer average temperature rise, the buoyancy reference velocity and the total smoke mass flow rate out of the compartment, as a function of the different parameters mentioned. Based on the experimental findings, it is discussed that different manual calculation methods, widely used for natural ventilation design of compartments in the case of fire, under-predict the hot layer thickness and total smoke mass flow rate, while the hot layer average temperature is over-estimated.     

Stack effect of smoke for an old-style apartment in Taiwan

Many existing apartments in Taiwan allow parking of motorcycles on the 1st floor along the arcade. For the purposes of lighting and ventilation, there is an opening in upper of the gates. Taking motorcycle arson as a fire scenario, this study proved that smoke would move into the building quickly via the opening and flow upward through the staircases, posing a serious risk whenever motorcycle arson was committed. The simulation results from FDS demonstrated that the visibility decline is very fast inside staircase. When the opening was moved to the bottom of the gate, the decline became slow because the stack effect phenomenon was effectively diminished. Image-recording and laser smoke layer measurement equipment was used to measure smoke diffusion, referring to the Australian Standard, AS 4391-1999 “Smoke management systems-Hot smoke test”. The experiments were executed in a five-story building by recording visibility at a height of 1.8 m on each floor. The results indicated the same conclusions when the opening was moved to the bottom of the gate. The results also verified that the door in the attic staircase was open; the stack effect was very significant.     

Fire detection using smoke and gas sensors

Fire detection systems located in aircraft cargo compartments are currently based only on smoke detectors. They generate about 200 false alarms per year for US registered aircraft. The number of false alarms is growing as more planes are outfitted with smoke detectors and air travel expands. Moreover, the survivability of an aircraft in a fire scenario depends on the early detection of the fire. A fire detection system is developed based on the simultaneous measurements of carbon monoxide, carbon dioxide, and smoke. The combination of the rates of rise of smoke and either carbon monoxide or carbon dioxide concentration provides a potential fire alarm algorithm to increase the reliability of aircraft smoke detectors, and to reduce the time to alarm. The fire detection system with the alarm algorithm detected fires that were not alarmed by smoke sensors, and alarmed in shorter times than smoke sensors operating alone.     

Application of Code Approach for Emergency Evacuation in a Rail Station

This paper presents an emergency evacuation analysis during a mid-platform train fire in an underground rail station. A time-based evacuation scenario is developed taking into account the stairway inaccessibility due to smoke blockage. The calculation approach in NFPA 130 is then applied to a parametric study of this time-based scenario and its reliability is examined using a micro-simulation model. Both methods give consistent predictions of the exiting times. The results demonstrate that with the division of the station into two zones, the exiting time could not meet the code requirements, whereas it does meet the required exiting time without the division. Such division is due to smoke blockage and creates an uneven ratio of the occupant load to the available exiting capacity. This shows that appropriate consideration of the fire and smoke effects is important for station egress evaluation. Other issues such as the fire growth rate and the pre-evacuation time are also discussed.