“干千年,湿千年,干干湿湿两三年”这句谚语,说的是木材含水率与木材使用年限的关系。木材含水率很小或很大时,木材使用的年限都较长。而处于半干半湿或时干时湿情况下的木材,则因容易引起腐朽,使用年限就很短,往往3～5年就可能破坏。因此木结构不宜用在半干半湿或时干时湿的环境中。 “Kilometer millennium, wet millennia, wet and dry for two or three years” is a saying that refers to the relationship between wood moisture content and the age of wood. When the wood moisture content is very small or very large, the wood is used for a longer period of time. In the case of wood that is semi-dry, semi-humid or when it is dry, it is likely to cause decay, and its useful life is very short. It can be destroyed in 3 to 5 years. Therefore, wood structures should not be used in semi-dry or wet-dry environments.