通过对不同含水率的山杨原木试件进行检测,分析了含水率对腐朽和健康木材电阻与应力波传播速度的影响,及其对2种检测技术误差率的影响.结果表明:(1)随着含水率的提高,原木试件健康和腐朽区域的电阻均先减小后趋于平稳,但相同含水率下,腐朽区域木材电阻低于健康木材;(2)采用电阻断层成像仪检测腐朽缺陷面积的误差率随含水率的提高有差异(最大误差率为37.83%,最小误差率为2.48%),含水率在36.13%~81.79%时误差较小,腐朽缺陷检测较接近真实值;(3)应力波传播速度随着木材含水率的提高先降低后趋于平稳.应力波二维图像检测腐朽缺陷面积的准确率随着含水率的变化也有差异,最大误差率为52.61%,最小误差率为17.78%,腐朽缺陷检测准确性比较高的含水率为20.23%~71.58%;(4)通过2种方法测试腐朽缺陷面积的对比研究,结果表明电阻断层成像的腐朽缺陷识别优于应力波二维图像.%To investigate the effect of moisture content on accuracy of electrical resistance and stress wave of timber, Populus David-iana timber samples under different moisture contents were analyzed by electrical resistance tomography ( ERT ) and stress wave tomography ( SWT) . Results showed that when moisture content increased the electrical resistance of both healthy and decayed tim-ber samples decreased, and then stayed steady when the moisture contents were over 80%. Electrical resistances of the healthy tim-ber were averagely higher than those of decayed ones. Accuracy of ERT was relatively high when moisture content of timber ranged between 36.13% and 81.79%, with the minimum error ratio being 2.48% ( maximum error ratio at 37.83%) . Velocity of stress wave reduced and then stayed steady when moisture content increased. Detection by stress wave was relatively accurate when the moisture content ranged between 20.23% and 71.58%, with the minimum error ratio being 17.78% (maximum error ratio at 52.61%). To summarize, ERT was more accurate than SWT in term of decayed area. Nevertheless, moisture content of timber should be taken in-to consideration when detecting decayed area via ERT.
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