Abstract Hygric properties of porous building materials are important for hygrothermal analysis. Their experimental determination is however not always reliable, shown by the discrepant results from different laboratories on the same materials. In this study, a recent round robin campaign initiated by KU Leuven (Belgium) and participated in by eight institutes from different countries is reported. Ceramic brick was selected as the target material. The bulk density and open porosity from vacuum saturation tests, the capillary absorption coefficient and capillary moisture content from capillary absorption tests, and the vapor permeability from cup tests were measured. Results were analyzed statistically and compared with a previous round robin project, EC HAMSTAD. The reproducibility errors for determining the capillary absorption coefficient were noticeably reduced when compared with the EC HAMSTAD project, and the different laboratories in the present study obtained similar results from vacuum saturation tests and capillary absorption tests without a common protocol. For cup tests, large inter-laboratory discrepancies still exist. However, with a stringent common protocol different laboratories achieved consistent results. For all properties a common protocol did not change the average results of all laboratories.

中文翻译：

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多孔建筑材料的吸湿性 (VI)：循环运动

摘要 多孔建筑材料的吸湿特性对于湿热分析非常重要。然而，他们的实验测定并不总是可靠的，不同实验室对相同材料的不同结果表明了这一点。在这项研究中，报告了最近由 KU Leuven（比利时）发起并由来自不同国家的八个研究所参与的循环运动。陶瓷砖被选为目标材料。测量来自真空饱和度试验的堆积密度和开孔率，来自毛细吸收试验的毛细吸收系数和毛细水分含量，以及来自杯试验的蒸汽渗透率。结果进行了统计分析，并与之前的循环项目 EC HAMSTAD 进行了比较。与 EC HAMSTAD 项目相比，确定毛细管吸收系数的重现性误差显着降低，本研究中的不同实验室从真空饱和度测试和毛细管吸收测试中获得了相似的结果，但没有共同的协议。对于杯测，实验室间仍然存在较大的差异。然而，通过严格的通用协议，不同的实验室取得了一致的结果。对于所有属性，通用协议不会改变所有实验室的平均结果。不同实验室采用严格的通用方案取得了一致的结果。对于所有属性，通用协议不会改变所有实验室的平均结果。使用严格的通用协议，不同的实验室取得了一致的结果。对于所有属性，通用协议不会改变所有实验室的平均结果。