Design and testing of innovative materials for passive fire protection

This study focuses on the characterization of panels for passive fire protection made with new composite materials, based on basalt fibers and both organic and inorganic impregnating matrixes. These materials were experimentally investigated to assess their suitability to bear strict exercise conditions imposed by accidental flame impingement. To this end, an experimental facility was specifically designed to simulate jet fires at laboratory scale. The behaviour and the response of different types of materials were characterised by determining temperature profiles, weight losses and time for rupture under conditions of flame impingement. Compared to other materials, basalt-based composites present low wall temperatures and good residual strength, which retard the panel failure. As a consequence, basalt fibers may be considered as key components for the development of novel shields for PFP.     

A simulation model for fire growth on materials subject to a room-corner test

A mathematical model has been developed to simulate fire growth on wall and ceiling materials when subject to a room-corner fire test exposure. The model predicts the area of burning, the upper layer gas temperature, and the rate of energy release as a function of time. Material fire property data are developed from apparatuses described in ASTM E 1321 and E 1354. The results compare favorably to experimental data generated in Sweden for 13 materials tested. Furthermore, the model shows the sensitivity to ‘flashover’ for thin materials relative to small variations in their property data.     

消防给水设施建设及理论探讨

针对目前消防给水设施建设的整体发展情况,分析了存在的问题,从防火审核、消防验收和灭火救援角度提出了消防给水设施必须按照规范进行建设的意见,并建议结合实际,创造性地改进消防给水设施建设的措施和解决方案.     

建筑火灾结构安全数值模拟框架

为了模拟建筑火灾过程中的火灾发展、结构响应及其相互作用提出了该模拟框架。该框架以现有的火灾模拟和结构分析数值模拟软件为基础,通过对其输入文件和模拟结果文件所含信息进行重新建模构成建筑火灾过程的数据环境,根据物理实验研究成果开发了材料高温强度退化和结构破坏方面的数值分析模块,与基础模拟软件一起构成覆盖灾难全过程的数值环境。该框架采用了面向对象的数据建模方法和系统集成技术,使得不同模拟模块的数据对象相互对应并协调工作,并能自动控制各模块实现对火灾过程的模拟,实现了在一个数据环境和一个软件平台上进行建筑火灾结构安全模拟。该框架为建筑火灾研究提供了数值实验方法,具有廉价和快速的特点,也是将实验室研究成果应用于具体建筑仿真的途径,对于建筑火灾性能化设计,消防救援预案的确定和火灾风险评估具有实用价值。     

A probabilistic occupant response model for fire emergencies

The present paper describes a probabilistic occupant response model for fire emergencies, which is integrated into a fire risk analysis model called CUrisk. Based on the PIA process, i.e., Perception, Interpretation and Action, the occupant response model predicts the probabilities of occupants perceiving fire signals due to direct perception, receiving fire alarms due to the activation of local alarms, sprinklers, the central alarm and the voice alarm, being warned by the other occupants and fire department, and taking actions including pulling the fire alarm, warning other occupants, calling the fire department, and commencing evacuation. The occupant response model is applied to predict the probabilities of evacuation initiation for a number of scenarios that consider combinations of fire detection and alarm systems for a mid-rise building. The results of the model show that asleep occupants need much longer response time to start evacuating and have lower probabilities of starting evacuation than awake occupants, which are consistent with what is observed in reality. Additionally, fire protection systems with only local alarms and only sprinklers connected to the central alarm can be improved significantly with systems with smoke detectors alone or combined with sprinklers connected to a central alarm, which result in higher probabilities of evacuation initiation with shorter delay times.     

建筑火灾中人的有效逃生和消防器材的应用

有效逃生是建筑防火的核心命题 有效逃生概念的提出 消防技术产品的发展体现在硬件上的极大丰富和完善。这主要是指增加阻燃材料在建材中的应用，能够显著提高建筑本身的防火能力，在不超出阻燃材料所能承受的火灾荷载前提下，保证建筑的稳定性；另一方面，配备消防和防火工程系统，增加建筑防火器材，保证建筑在火灾中的稳定；第三方面，要增加建筑内部居住和使用人员对火灾的认知程度，使建筑消防技术得以在真正意义上的体现。     

FOCUS: A computer simulation model for fire control planning

The U.S. Forest Service has been working toward the development of a mathematical model that is expected to point the way to improved efficiency in forest fire fighting and fire prevention.     

消防设施综合信息平台的数据交换设计

介绍消防设施综合信息平台的组成,着重介绍其4个业务子系统。数据交换平台是消防设施综合信息平台的关键组成部分,阐述搭建数据交换平台的总体思路、体系结构及基于Web服务的实现方法,并介绍利用数据交换平台实现消防部队远程监管系统的简要步骤和功能。     

A strategy for the fire testing of reduced scale structural models

A strategy for the fire testing of reduced scale structural models is developed which takes into consideration all significant thermostructural responses. An investigation of the thermal distributions within a structural element allows fire curve, thermal input and structural displacement output to be linked as cause and effect. Dimensional analysis permits the definition of the conditions necessary for dynamic similarity between model and prototype. An equivalent model fire curve is derived which can be mapped by a simple time scale factor on to a standard fire curve, though distortions due to film effects are noted. Errors due to temperature dependent properties are removed due to the nature of model and prototype temperature distributions. The principles are sensibly validated by low temperature experiments on perspex models of different scales. Finally, it is noted that a model test method would be advantageous for the provision of statistically meaningful amounts of indicative test data, with particular reference to parametric investigations. However, it is recognized that one-off full-scale tests must be conducted to provide the best final assessment of fire resistance.Nomenclature d structural element depth or thickness - d _m ;d _p thickness of model and prototype elements - E elastic modulus - F force on a small element slice - h _f film coefficient - k thermal conductivity - L significant longitudinal dimension or span - L _m ;L _p lengths in model and prototype - q heat flux - s scale factor - t generalized time interval - t _m ;t _p model and prototype test time scales - T generalized temperature - T _e equivalent linear temperature distribution - T _f furnace temperature - T _o average temperature through the thickness - T _x curvelinear temperature distribution - T _w element surface temperature - T ₁ –T ₅ thermocouple temperatures through the thickness - u lateral extension - y lateral displacement or bow - coefficient of linear thermal expansion - thermal diffusivity - T temperature difference over the thickness - slenderness ratio - ₁... _n dimensionless groupings - stress in element - _y material yield stress - () _m reference to model test variables - () _p reference to prototype test variables     

室外消防给水设施问题探讨

室外消防给水设施对于确保建筑物火场扑救成功有非常重要的意义,通过对室外消防给水设施设置中的几个问题展开探讨,提出了利用游泳池和景观水池作为消防水池的可行性,阐述了室外大区域消防供水中消防车取水井的设置合理性及室外消防给水管道设置的安全性。     

加强建筑消防设施标准化管理的思考

在系统总结新疆开展建筑消防设施规范化管理经验的基础上,深入分析当前建筑消防设施管理中存在的主要问题,并从发挥政府宏观调控作用,加强消防工程施工质量监管,健全消防安全评价体系,协调处理消防设施使用单位、消防中介组织和保险商三方利益关系,调动全社会参与积极性等方面,提出了综合应用行政手段和市场手段深入推进建筑消防设施管理的对策。     

Sensor-steered fire simulation

A sensor-linked modelling tool for live prediction of uncontrolled compartment fires, K-CRISP, has been developed in order to facilitate emergency response via novel systems such as FireGrid. The modelling strategy is an extension of the Monte-Carlo fire model, CRISP, linking simulations to sensor inputs which controls evolution of the parametric space in which new scenarios are generated, thereby representing real-time “learning” about the fire. CRISP itself is based on a zone model representation of the fire, with linked capabilities for egress modelling and failure prediction for structural members, thus providing a major advantage over more detailed approaches in terms of flexibility and practicality, though with the conventional limitations of zone models. Large numbers of scenarios are required, but computational demands are mitigated to some extent by various procedures to limit the parameters which need to be varied. HPC (high performance computing) resources are exploited in “urgent computing” mode. The approach adopted for steering is shown to be effective in directing the evolution of the fire parameters, thereby driving the fire predictions towards the measurements. Moreover, the availability of probabilistic information in the output assists in providing potential end users with an indication of the likelihood of various hazard scenarios. The best forecasts are those for the immediate future, or for relatively simple fires, with progressively less confidence at longer lead times and in more complex scenarios. Given the uncertainties in real fire development the benefits of more detailed model representations may be marginal and the system developed thus far is considered to be an appropriate engineering approach to the problem, providing information of potential benefit in emergency response.     

电缆燃烧典型火源模拟方法综述

针对电缆火灾问题,综述了国内外电缆火灾模拟试验及电缆燃烧测试中使用的火源模拟方法,并对比探讨了多种火源模拟方法的点火时间、火源温度、火源面积、火源功率、可扩展性、可移动性以及可持续使用性等方面的差异:燃气喷灯法和辐射加热法(锥形量热计)所需点火时间短;电加热法火源温度高,操作简便易移动;燃油点火法的点火面积大,可扩展性...     

A smoke detector activation algorithm for large eddy simulation fire modeling

This study chronicles the development and integration of a smoke detector activation algorithm (known as the SDAA) that describes the response time of a smoke detector into a large eddy simulation (LES) fire model [Roby RJ, Olenick SM, Zhang W, Carpenter DJ, Klassen MS, Torero JL. Smoke detector activation algorithm version 1 technical reference guide. NISTIR Report; 2006, in press]. Although the SDAA could be used with any CFD smoke movement model, the results here address specifically its application to the fire dynamics simulator (FDS). The fire model predicts the smoke concentration and velocity adjacent to the detector while an algorithm based on characteristic velocity-based lag times describes the transport of smoke into the sensing chamber of the smoke detector. The experimental data from a multi-room compartment fire were used for comparison and a series of benchmark studies provide a mechanism to establish the sensitivity of the model to the different input parameters. The SDAA was found to be very accurate in determining detector activation times for both high- and low-velocity smoke flows.     

The simulation of fire sprinklers thermal response in presence of water droplets

When a fire occurs, the sprinkler closest to the location of the fire typically activates first and releases water droplets into the rising plume of hot gases. Part of these droplets is entrained by the plume and may impact on adjacent sprinklers providing evaporative cooling and thus delaying their activation. The model of the thermal response of sprinklers in these conditions suggests the introduction of the concept of equivalent cylindrical links: a solid metallic cylinder is said to be equivalent to a given fire sprinkler link if it reaches the activation temperature of the sprinkler at the same time, both in dry conditions and in presence of water droplets carried by the hot gas flow. Tests are conducted on both fire sprinklers and equivalent cylindrical links to validate this theoretical approach. The results compare favorably both in dry and wet conditions for the range of parameters considered in this study. Therefore, this approach enables the transient quantification of the sprinkler thermal response in an actual fire scenario such as a large-scale fire test.     

穿越建筑物的消防车道作为防火分隔的可行性研究

借用森林防火中"防火带"的概念,拟采用一定宽度的消防车道替代防火墙的方式解决防火分区划分的问题,并对其可行性进行研究.     

应急消防救援装备管理系统设计

建立基于图文交互技术的应急消防救援装备管理系统,提高应急装备的信息化管理水平。根据系统的整体建设目标提出了功能架构;通过文本生成方法,自动为可视化图表添加文字描述,增强用户对数据的理解;在文本中嵌入迷你图,链接文本和可视化图表两种表现形式,实现交互式数据分析报告,从而帮助用户进行数据的可视化探索。以某消防装备统计为例,对基于图文交互技术的应急消防救援装备管理系统进行交互式报告应用验证,结果表明文本和可视化相结合能互相丰富,增强用户理解数据的能力。     

确保海上设施的消防安全

在恶劣的极具挑战的海洋气候条件下，选择1套适当的火灾探测系统无疑是一个明智的选择。 海风极具腐蚀性，对敏感的电子设备危害甚重。像航运业、化工厂和近海石油钻塔等近海设施，常产生超均标的震动和噪音。而且，这些设施所在地通常在空间和电力供应方面受到诸多限制。当腐蚀、震动、噪音、有限的空间和供电问题变得司空见惯时，“海上”这一称谓必须据其特点提供应对不同形势的特殊要求。