结构用杉木规格材含水率与抗弯性能关系研究

Relationship between Moisture Content and Bending Property of Chinese Fir Structural Lumber

按照动态弹性模量合理配组杉木规格材,通过调节不同的含水率,全尺寸破坏性地测试其抗弯性能,建立了杉木规格材抗弯性能和含水率之间关系,并与其他调整模型相比较,提出了利用含水率来调整中国杉木规格材抗弯性能的简要方法.研究结果表明:杉木的低抗弯强度与含水率之间存在二次函数关系,而杉木的抗弯弹性模量和高抗弯强度与含水率之间存在幂函数关系.

Chinese fir dimension lumbers were sorted into three matched test groups by dynamical modulus of elasticity（MOE）. Three groups were conditioned to different moisture contents, respectively. The bending property of dimension lumbers was tested in full size. The models between bending property vs. moisture content relationships were proposed and compared with other models developed earlier. Simplified procedures were provided for adjusting bending porperty of Chinese fir dimension lumber for moisture content which is suitable for materials properties codes or standards. The results indicate that there exists a quadratic relation between the low modulus of rupture（MOR） and moisture content while MOE and the high MOR and moisture content show a power function.