基于HAM模型的竹材热湿物理性质试验研究

为获得典型竹材的材性参数,明确竹木之间以及不同竹材之间的差异,选择整竹展平板、竹集成材、竹胶合板、竹重组材、竹刨花板、大片竹材定向刨花板等6种代表性产品,系统地进行基于建筑围护结构HAM模型的热湿物理性质测试.项目包括:测定基本物理性质的密度计算和真空饱和实验;测定湿储存性质的平衡吸放湿实验;测定湿传递性质的毛细吸水实验、蒸气渗透实验和干燥实验;测定热储存性质的热分析;测定热传递性质的导热系数测试和表面光热性质测试.测试结果初步形成竹材热湿物理性质的参数基础;与18种木材产品的对比表明,竹材湿储存和湿传递性质普遍小于木材,而同时表征热储存和热传递性质的蓄热系数大于木材;6种竹材之间的对比表明,竹材改性有利于均匀性的提高,可拓展其材性频谱范围,并使区别于木材的特性得到强化.

Experimental Study on Thermal and Hygric Physical Properties of Bamboo Based on HAM Model

To obtain the material parameters of typical bamboos and explore the distinction between bamboo and timber as well as among different bamboo products, flattened bamboo panel (FB), bamboo laminated lumber (BSB), plybamboo (BMB), bamboo scrimber (BFB), bamboo particleboard (BPB), and bamboo OSB (BOSB) were systematically tested for thermal and hygric physical properties based on the material parameter requirement of heat-air-moisture transfer model (HAM model). The items included density calculation and vacuum saturation test for basic properties, sorption test for moisture storage properties, capillary absorption test, water vapour transmission test and drying test for moisture transport properties, thermal analysis for heat storage properties, thermal conductivity test, surface light and thermal properties test for heat transport properties. The test results initially formed a data basis of thermal and hygric physical properties that could provide support for the bamboo application in the building envelope. The comparison with 18 reference timbers showed that the moisture storage and moisture transport properties of bamboo were generally lower, while the thermal storage coefficient that characterized heat storage and heat transport properties were higher. The comparison among 6 bamboo products showed that modification treatment improved the homogeneity, broadened the spectrum of material properties, and strengthened the distinction with timber.