基于文化遗产价值的闽浙木拱廊桥防火策略

Fire Prevention Strategy of Wooden Arch Covered Bridge in Min-Zhe Area Based on Cultural Heritage Value

为了保护闽浙木拱廊桥这一重要的文化遗产免受火灾的侵袭,提出了基于木拱廊桥文化遗产价值的防火策略。通过梳理闽浙木拱廊桥的遗产价值,统计相关的火灾事故次数与起火原因,并对近年来3起木拱廊桥火灾事故的起火原因、起火点、火势蔓延路径、燃烧时间与火灾后果等进行详细调查,以了解木拱廊桥火灾的特点。基于这一调查结果及遗产保护的真实性原则,对现有的木拱廊桥防火措施进行分析。结果表明:编木拱结构和廊屋所承载的多重功能与精神空间体系是其遗产价值的核心,也是火灾中易燃的两大主要部分;木拱廊桥火灾的起因主要是意外失火,火源主要来自桥面的人为活动,而其结构耐火等级低、廊屋与编木主拱立体燃烧、扑救困难则是火毁后果严重的主要原因;现有策略中,除防止祭祀香火火源取得较好效果外,禁烟、控制火源、火情监测、灭火等方面措施不足,成效不佳,应开展禁烟方式和火情人工监测的改进、火灾监测和灭火设备的研发;通过对部分木构件的表面防火涂覆、铺设难燃材料等措施建立桥梁上下、多跨桥跨间以及桥梁与周围森林或建筑物之间的分区,在尽可能不破坏文化遗产真实性的前提下,提高桥梁本身的防火、抗火能力。

To protect the important cultural heritage of the wooden arch covered bridge in Min-Zhe area,a fire prevention strategy based on cultural heritage value was proposed.The heritage value of the Min-Zhe wooden arch bridge was combed,the number and causes of related fire accidents were counted,and the fire causes,origins,spread paths,burning time and consequences of three Min-Zhe bridges happened in recent years were investigated in detail to understand the characteristics of fires in such kind of bridges.Based on this survey and the authenticity principle of heritage conservation,the existing fire prevention measures of the Min-Zhe bridge were analyzed.The results show that the multiple functions and spiritual space system carried by the wood arch structure and the covered house are the core of its heritage value and the two main parts of flammability in the fire.The main cause of the fire on the Min-Zhe bridge is accidental misfire,and the fire origin mainly comes from human activities on the bridge deck.The low fire resistance grade of the bridge structure,the three-dimensional combustion of covered house and woven arch structure,and the difficulty of extinguishing are the main reasons for the serious consequences of the fire damage.Among the existing strategies,except the ban of sacrificial incense has achieved good results,other measures such as smoking ban,fire control,fire monitoring,fire extinguishing are insufficient and ineffective.The improvement of smoking ban methods and manual monitoring of fire conditions,and the research and development of fire monitoring and extinguishing equipment should be carried out.Through coating the surface of some wood components and laying of refractory materials and other measures,the fire prevention zoning between the upper and lower bridges,among the multi-span bridge spans,and between the bridge and the surrounding forests or buildings was established,in order to improve the fire prevention and resistance of the bridge itself with minimal harm to the authenticity of cultural heritage.