运用时温等效原理研究含水率为0.6％的木材试样的动态黏弹性质.在25 ～ 150℃温度范围内,通过频率扫描(0.1 ～20 Hz)试验获得不同恒定温度水平下木材的贮存模量和损耗因子值.将其他温度下的黏弹性曲线通过水平移动因子平移并叠合连接至参考温度(本研究中为135℃)曲线,分别生成一定频率范围内的贮存模量和损耗因子主曲线.通过最小二乘拟合法,采用Arrhenius方程对水平移动因子与温度的关系曲线进行拟合分析.结果表明:贮存模量主曲线的水平移动因子与温度的关系曲线在25 ～150℃内满足Arrhenius方程,因此利用时温等效原理描述木材的动态刚度性质是适用的;但时温等效原理无法预测木材的松弛转变行为.%Time-temperature superposition principle ( TTSP) was used to examine dynamic viscoelastic properties of Chinese Yr{Cunninghamia lanceolata) wood at an extremely low moisture content(0.6% ). Storage modulus and loss factor data were obtained at different constant temperatures ranging from 25 ℃ to 150 ℃ in frequency multiplexing experiments (0. 1-20 Hz). All viscoelastic curves at other temperatures were shifted along the log-frequency axis to superimpose them on a reference temperature (I. E. 135 ℃ in this study) curve. The extended storage modulus and loss factor isothermal master curves were over a wide range of frequency. The shift factors were determined to be a function of temperature and fitted into the Arrhenius equation with the least squares method. The results showed that the storage modulus data were excellently fitted into the Arrhenius model, indicating the validity of the model to characterize the dynamic stiffness behavior of dry wood in the range of 25 - 150 ℃. Using the TTSP. However, the time-temperature equivalence was not able to predict the damping properties.
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