【作者】 徐亮；

【导师】 张和平；

【作者基本信息】 中国科学技术大学 ， 安全技术及工程， 2007， 博士

【摘要】 热塑性装饰材料因其质轻、便宜、加工方便和防水、耐腐蚀等优点，在建筑中得到了广泛的应用。然而热塑性装饰材料在建筑火灾中，会释放出大量的有毒烟气，通过壁面火蔓延或流动火蔓延，为火灾向邻区发展提供通道，扩大火灾面积并强化室内火灾，加速室内火灾的发展过程。以往的装饰材料火灾研究主要集中在“热固型”材料，对于热塑性装饰材料的火灾行为研究非常少，热塑性材料的受热流动特性其火灾行为与“热固型”材料的火灾行为有很大的差异，因此本文的目标是对热塑性装饰材料的火灾特性进行研究。根据实际情况选取了五种常见的热塑性装饰材料PP(聚丙烯)、PE(聚乙烯)、PS(聚苯乙烯)、PMMA(聚甲基丙烯酸甲脂)和PVC(聚氯乙稀)装饰板作为研究对象，运用小尺寸实验和全尺寸实验相结合的方法进行火灾特性研究。小尺寸实验采用热失重分析仪(TG)和锥形量热仪(Cone)，热失重分析仪用于研究材料的热解特性，分析了材料在空气中的热解过程和热解动力学，为热塑性装饰材料火灾行为的研究提供最基础的支持。锥形量热仪用于研究材料的小尺寸燃烧性能，分析了材料厚度与外加热辐射通量对材料的点燃时间、热释放速率和质量损失速率等火灾参数的影响。利用无量纲化、数值模拟和线性拟合的方法建立了预测热薄型、热中型和热厚型材料的点燃时间公式，以无量纲热辐射通量的形式给出了各预测公式的适用范围，并验证了其可靠性。目前建筑装饰材料的对火行为测试标准很难能够反映热塑性装饰材料的火灾行为，因此本文根据火灾中热塑材料的受热行为，基于ISO 9705热释放速率实验台，设计并搭建了热塑性装饰材料火灾行为实验平台。利用该实验平台研究了材料种类、材料厚度、点火源功率、地板材料和熔融流动能力对热塑性装饰材料全尺寸火灾行为的影响，测量了热释放速率、油池与油池火面积、火焰高度等关键的火灾参数。通过对实验数据的分析提出了热塑性装饰材料的流动燃烧与固体表面燃烧两种燃烧形式，运用材料热解机理对燃烧形式进行了解释，分析得到影响热塑性装饰材料火灾行为的重要因素。在实验研究文献分析基础上，提出了热塑性装饰材料火灾过程模拟的困难与方向，利用场模拟软件FDS对热塑性装饰材料固体表面燃烧过程进行了模拟计算，分析了FDS对固体表面燃烧过程模拟的适用性。根据顺流火蔓延理论，推导了无点火源作用下壁面向上火蔓延的计算公式，并对固体表面燃烧火灾过程进行了模拟，验证了推导的计算公式的适用性。更多还原

【Abstract】 Thermoplastic lining materials, due its light weight, low cost, easy manufacturing, waterproof, are widely used in all types of buildings to cover floors, walls and ceilings. When subject to fire, thermoplastic materials would release lots of toxic smoke, provide routes to adjacent zones through surface flame spread or melt flow flame spread, increase fire area, intensify and accelerate enclosure fire growth.Previous research was focused on ’thermoset’ materials, which do not show melt flow in fire, and there were little research on thermoplastic linings, whose melting behavior makes it different from other materials. The aim of this thesis is to study the fire performance of thermoplastic linings. The most common commercial thermoplastic linings, PP, PE, PS, PMMA and PVC, were selected and tested on small scale and large scale experiments to explore their fire behavior.Small scale experiments were carried out on thermogravimetry and cone calorimeter respectively. Through thermogravimetric analysis, materials’ thermal decomposition characteristics were studied, the process and kinetics of thermal decomposition were analyzed and discussed, which provided foundermental support for fire performence research on thermoplastics. Combustibility were studied through cone calorimeter, the effect of lining thickness and external irradiance levels on ignition, heat release rate and mass loss rate were investigated. Based on dimensionless analysis, numerical calculation and linear regression methods, formulae of ignition for thermally thin, intermediate thermally thick and thermally thick materials were established with applicable range given in the form of dimensionlessparameter for each formula, and the reliability were proved through comparison with experiments and literature.Since there are no published ’standard tests’ capable of revealling real fire performance of thermoplastic linings, especially the melt flow behavior, a rig for test on fire behavior of thermoplastic linings was established based on the ISO9705 heat release rate measurement platform. The effect of material type, thickness, ignitor, flooring and melt flow viscosity were explored, the parameters such as heat release rate, pool and pool fire growth, lining surface temperatures, pool temperatures and flame height were obtained. Through the data analysis, two types of burning modes for thermoplastic linings, melt flow burning and solid surface burning, were discovered, the reasons for each mode were explained with the thermal decomposition mechanisms and the important factors affecting thermoplastic lining fire behavior were identified.Difficulties and advices for simulation of thermoplastic lining fire behavior were put forward based on expermtal research and literature. CFD software FDS was used to simulate solide surface burning process, and its applicability was discussed. A formula for upward flame spread without ignitor, which is proved to be capable of simulating the solide surface combustion, was deduced from the concurrent flame spread theory.更多还原