應用時間溫度疊加原理評估熱處理材之潛變行為

The Application of Time-Temperature Superposition Principle for Evaluating the Creep Behavior of Heat-treated Wood

張豐丞(Feng-Cheng Chang) ； 楊德新(Te-Hsin Yang) ； 謝岱芸(Dai-Yun Hsieh) ； 林志憲(Chih-Hsien Lin) ； 卓志隆(Chih-Lung Cho)

《林產工業》 34卷3期 (2015/09) Pp. 109-119

https://doi.org/10.6561/FPI.2015.34(3).1

摘要

為評估熱處理材之長期變形，本試驗針對熱處理大葉桃花心木（Swietenia macrophylla）進行短期潛變試驗，應用時間溫度疊加原理（Time-temperature superposition principle，TTSP）繪製潛變主曲線，用以推估熱處理改質是否有效減緩木材潛變變形。由實驗結果可知，木材經過不同條件熱處理後勁度（Stiffness）皆有提升，其潛變變形小於未處理者，顯示熱處理可以有效改善木材在長期荷載下的潛變。此外，比較熱處理條件對木材勁度之影響可發現，不同熱處理溫度組間有顯著差異，而不同熱處理時間組間則無顯著差異。於本試驗短期潛變試驗的結果以時間溫度疊加原理平移後，所得之平移因子（Shift factor）分別以Williams-Landel-Ferry equation（WLF）方程式及Arrhenius方程式進行擬合，其中以WLF方程式較為適用。

關鍵字

潛變 ； 熱處理材 ； 時間溫度疊加原理

並列摘要

In order to investigate the long-term performance of heat-treated wood, this study conducted a series of short-term creep tests for heat-treated Swietenia macrophylla, and the time-temperature superposition principle (TTSP) was applied to construct creep master curves, to evaluate the effect of heat treatment on the creep deformation of wood. The experimental results showed that, after heat treatments with various temperatures and durations, the stiffness of wood increased and the creep deformations of each group were smaller than that of untreated wood, indicating that heat treatment could effectively improve the performance of wood under long-term loading. Moreover, considering the effect of heat treatment on the stiffness of wood, there were significant differences among groups of different treatment temperatures, whereas no difference among groups of different treatment durations was found. In addition, the shift factors obtained from TTSP in this study were curve-fitted by Williams-Landel-Ferry (WLF) equation and Arrhenius equation, and the results suggested that the WLF is more suitable in this case.

並列關鍵字

Creep ； Heat-treated wood ； Time-temperature superposition principle (TTSP)