Stress Wave Vibration Method of Investigating the Properties of Standing Tree and Its Application on Growing Plantation Trees

在日本，为了提高产量，必须利用针叶树人工林。然而，利用群体对优质原木的需求及其有效供应是不确定的条件或环境。如果能够在立木状态下获得材料的质量，则工厂内生产线中伐木计划的制定和原木的分配就可以轻松而正确地执行。为此，进行了本实验，并将为期2年的实验结果总结如下。1)验证了通过测量应力波传播速度可以确定立木的质量（MOE）。认为所有立木的密度应为0.80 g/cm^3。但是，还需要进一步研究密度和含水量的影响。2)采用上述方法，立木和加工材料的实测MOE值相同。从立木和干料中获得的值之间的相互依赖性或相关性也很高。3)基于应力波法获得的MOE，尝试对森林木材资源进行成本评估。4)提出了杉木材料利用体系中立木强度分级的方法。这项研究的结果有望在合理利用国内木材资源方面得到鼓励。

In Japan, increasing production necessitates the utilization of coniferous tree plantation species. However, the utilizing groups' demands for quality logs and its efficient supply are under uncertain conditions or circumstances. If the quality of the material can be obtained while in the standing tree state, establishment of the cutting plans and the distribution of logs in the manufacturing line in the factory can be easily and properly executed. On this account, this experiment was conducted and the results for a 2-year period are summarized below.1) It was verified that the quality (MOE) of the standing tree can be determined by measuring the velocity of stress wave propagation. It was considered that the density for all standing trees should be 0.80 g/cm^3. However, further investigation on the effects of density and moisture content are necessary.2) Considering the above-mentioned method, the measured MOE values of ythe standing trees and processed materials were the same. The interdependence or the correlation between the values obtained from the standing trees and the dried materials was also high.3) Based on the MOE obtained by means of the stress wave method, the cost assessment of the forest wood resources was tried.4) Moreover, grading of standing tree according to strength in the utilization system of Sugi material is proposed. Results of this research is expected to be encouraged in the rational utilization of domestic wood resources.