樹種對三種非破壞性測定儀檢測木材彈性係數之影響

Influence of Wood Species on the Modulus of Elasticity of Wood with Three Kinds of Nondestructive Test Instruments

陳載永(Tsai-Yung Chen) ； 葉政翰(Jeng-Hann Yen)

《林產工業》 15卷2期 (1996/06) Pp. 285-294

https://doi.org/10.6561/FPI.1996.15(2).7

摘要

以杉木、美國鐵杉、冰片樹及橡膠木為試材，其比重對應力波傳遞速度及振動頻率之影響趨勢不明顯；而試材比重與破壞性方法實測之靜曲彈性係數及靜曲強度成正相關之趨勢，其R^2值分別為0.55及0.77。四種樹種經三種非破壞性方法預測之動彈性係數與破壞性方法實測之靜曲彈性係數，其直線迴歸分析結果，就樹種而言，以橡膠木之相關性最高（R^2＞0.83）及杉木之相關性最低（R^2＜0.59）。就非破壞性檢測方法而言，以應力波計時儀之檢測結果與破壞性方法實測者最接近，約高出1～24%，而以打音頻譜分析系統檢測之結果大於破壞性方法實測者最多（18～58%）。

關鍵字

樹種 ； 非破壞性測定 ； 動彈性係數 ； 靜曲彈性係數

並列摘要

The China fir (Cunninghamia lanceolata), Western hemlock (Tsuga heterophylla), Kapur (Dryobalanops spp.) and Rubber wood (Heava brasiliensis) were used as test materials, the effect of wood specific gravity on the transmit velocity and vibrational frequency of stress wave showed the tendency not dear; but the static modulus of elasticity (MOE) and modulus of rupture (MaR) determinated by destructive test which increased with the wood specific gravity increased , their R2 was 0.55 and 0.77, respectively. The dynamic modulus of elasticity (MOE) values of four wood species were tested by three types of nondestructive test instruments which compared with the static modulus of elasticity (MOEd) values from destructive test. The results indicated by linear regression analysis showed that the results for rubber wood was the best (R^2＞0.83) and China fir was the worst (R^2＜0.59) in one side. In addition to, comparing the testing results of nondestructive test instruments and universal testing machine, the predicated values of MOEd from the stress wave timer were more similar to MOE, MOEd values were only 1~24% higher than the MOE, but the MOEd values from the tap tone analysis system were 18~58% higher than the MOE.

並列關鍵字

wood species ； nondestructive test ； dynamic modulus of elasticity (MOEd) ； static modulus of elasticity (MOE)