传统地仗保护木构件火灾机理和防火设计方法研究

Traditional timber buildings are important carriers of Chinese civilization, which should be maintained and renovated scientifically and reasonably. Plasters were usually used to protect timber members in traditional timber building from corrosion, insect and fire. Different with the materials like fire coating, gypsum boards commonly used as fire protection in modern timber buildings, plasters are comprised of many types of inorganic and organic substances. The influence of plasters on the fire performance of timber members was not well known. Therefore, it is necessary to study the fire mechanism of timber members with traditional plasters. Full-scale fire tests and cone calorimeter tests, theoretical and numerical analysis will be conducted in this project to comprehensively investigate the fire performance of timber members with traditional plasters. Their charring behavior will be studied through cone calorimeter tests and standard fire tests, and models will be developed for charring rate of timber species commonly used in China protected with plasters. Fire tests and numerical simulation will be carried out to study the fire endurance of timber members protected with plasters, model will be proposed, and equations to predict the fire resistance will be developed. The mechanical performance of timber members protected with plasters after fire will be experimentally and theoretically studied. Equations will be proposed to evaluate their residual capacities after fire. Based on the fire tests, theoretical analysis and simulation results, fire design methods considering the protection from the plasters will then be proposed for these timber members.

传统木结构建筑是中华文明传承的重要载体，应进行科学合理的保护和修缮。传统木结构构件表面通常采用地仗层，兼具防腐、防虫和防火作用。与现代木结构常用的防火涂料、防火石膏板等不同，地仗是由多种无机物和有机物按照一定配比调配而成的混合物，其对木结构的火灾蔓延和耐火性能的影响规律尚不了解。因此，需对传统地仗保护木构件的火灾机理进行研究。本课题拟通过明火试验、理论分析和数值模拟相结合的方法研究传统地仗保护木构件的火灾机理。通过锥形量热仪和试验炉明火试验研究传统地仗保护木构件的炭化机理，建立我国常用树种传统地仗保护下的炭化速度模型；进行传统地仗保护木构件耐火极限试验研究和数值模拟，建立理论分析模型并提出耐火极限计算方法；进行传统地仗保护木构件火灾后受力性能试验研究和参数分析，提出火灾后剩余承载力评估方法；在明火试验、理论分析和数值模拟基础上，提出考虑传统地仗保护有利作用的防火设计方法。

传统木结构建筑是中华文明传承的重要载体，应进行科学合理的保护和修缮。传统木结构构件表面通常采用地仗层，兼具防腐、防虫和防火作用，但其对木结构的火灾蔓延和耐火性能的影响规律尚不清晰。本项目通过明火试验、理论分析和数值模拟相结合的方法系统研究了传统地仗保护木构件的火灾机理。通过锥形量热仪和试验炉明火试验研究了传统地仗保护木构件的炭化机理，建立了传统地仗保护木材的炭化速度模型；完成了传统地仗保护木构件耐火极限试验研究和数值模拟，建立分析模型，揭示了传统地仗保护木构件热力耦合承载机理；完成了传统地仗保护木构件火灾后受力性能试验研究和参数分析，获得了传统地仗保护木构件火灾后剩余承载性能劣化规律；在明火试验、理论分析和数值模拟基础上，提出了考虑传统地仗保护特点的防火设计方法。