The service life of wood in outdoor use under humid conditions is mainly determined by its material resistance and the exposure situation. Different standards such as EN 350 (2016) point on the relevance of wood’s resistance against moisture for its expected service life. Recently, different standardized but also numerous nonstandardized methods were suggested to test the water permeability of wooden materials. In the context of this study, different European-grown soft- and hardwoods, tropical hardwoods, modified wood and wood treated with water- and oil-borne preservatives were subjected to floating and submersion tests according to CEN/TS 16818 (2018) and different short-term water uptake and release tests. Moisture performance data from field tests with the same materials were analyzed and used to assess the predictive power of different laboratory moisture indicators. The moisture characteristics suggested by CEN/TS 16818 (2018)—rm₁₆₈ (residual moisture content after water uptake and release processes) and res₃₁₂ (residue as a percentage of the absorbed moisture)—showed the little potential to predict the outdoor moisture performance of the tested materials. In contrast, the mean moisture content during absorption and desorption (MC_mean) predicted well the outdoor moisture performance of the materials under test. Short-term water uptake and release of small specimens also showed high predictive power.

中文翻译：

---

基于实验室指标预测木材的室外湿气性能

木材在潮湿条件下在户外使用的使用寿命主要取决于其材料抵抗力和暴露情况。诸如EN 350（2016）之类的不同标准指出了木材的抗湿性与其预期使用寿命之间的相关性。近来，提出了不同的标准化但也有许多非标准化的方法来测试木质材料的水渗透性。在这项研究的背景下，根据CEN / TS 16818（2018）对不同的欧洲种植的软木和硬木，热带硬木，改性木材以及用水和油性防腐剂处理过的木材进行了浮动和浸没测试，短期吸水和放水测试。分析了使用相同材料进行的田间测试的湿度性能数据，并将其用于评估不同实验室湿度指标的预测能力。CEN / TS 16818（2018）建议的水分特性-rm ₁₆₈（水分吸收和释放过程后的残留水分含量）和res ₃₁₂ （残留量占吸收水分的百分比）-预测被测材料的室外水分性能的潜力很小。相反，吸收和解吸过程中的平均水分含量（MC _mean）很好地预测了被测材料的室外水分性能。短期吸水和释放小样本也显示出较高的预测能力。