自然劣化对文物建筑木质构件热性能的影响

为探讨自然劣化对文物建筑木质构件热性能的影响，采用傅立叶变换红外光谱（FTIR）与差式扫描量热分析法（DSC）对4种文物建筑木质构件样品与云南松现代材样品进行官能基团和热稳定性能测定，讨论了自然劣化对其的影响。结果显示，较软木松而言，硬木松即使在自然劣化后仍然有着较好的耐燃性能。同时，木质构件在自然劣化过程中主要发生了木质素与半纤维素的分解。清代劣化材由于木质素含量减少，干燥阶段与固相燃烧阶段所需温度都有大幅度提前，更易热解。另外，虫害情况越严重，老化材纤维素含量越少，放热量随之降低，同时木构件化学结构越不稳定，劣化材干燥阶段所需温度随之降低，热解反应越剧烈。

The influence of natural deterioration on the thermal performance of wood components in heritage buildings

To investigate the effects of natural deterioration on the thermal performance of wood components for heritage buildings,the functional groups and thermal stability of four samples of wood components for conservation buildings and Pinus yunnanensis were determined using Fourier Transform Infrared Spectroscopy(FTIR)and Differential Scanning Calorimetry(DSC),and the effects of natural deterioration on these were discussed.The results showed that Hard Pines has better fire resistance than Soft Pines,even after natural deterioration.At the same time,the decomposition of lignin and hemicellulose occurs mainly during the natural deterioration of the wood components.Deteriorated timber of the Qing dynasty is more susceptible to pyrolysis as the lignin is reduced and the temperature required for both the drying,and solid phase combustion stages is significantly advanced.In addition,the more severe the insect damage,the lower the cellulose of the deteriorated timber and the consequent reduction in heat release.At the same time,the more unstable the chemical structure of the wood components,the lower the temperature required for the drying phase of the deteriorated timber and the more intense the pyrolytic reaction.