弦向角对应力波在原木横截面传播速度的影响

Effects of Tangential Angles on Stress Wave Propagation Velocities in Log's Cross Sections

为了研究应力波在原木横截面上传播时应力波波速的变化规律及其影响因素,选择柞木、红松、臭冷杉和大青杨4个树种的原木为试验材料,在原木的横截面上,测试不同弦向角所对应的应力波波速,并用MATLAB软件对弦向角和应力波波速进行曲线拟合。结果表明:1)随着弦向角的增加,应力波在柞木、红松、臭冷杉和大青杨原木横截面上的传播速度均呈3次曲线趋势增加;2)当弦向角大于36°时,应力波在大青杨原木横截面上的传播速度最快,在柞木原木横截面上的传播速度最慢;3)应力波在柞木、红松、臭冷杉和大青杨原木横截面上的径向最大传播速度分别为1109.0,1220.4,1245.8和1618.3m·s-1。

In order to study stress wave propagation velocities and those influencing factors in log＇s cross section,logs of Quercus mongolica,Pinus koraiensis,Abies nephrolepis and Populus ussuriensis were chosen as test materials to measure stress wave propagation velocities at different tangential angles.In addition,MATLAB was used to establish fitting models of stress wave propagation velocities and tangential angles.The results showed that nonlinear relationship existed between stress wave propagation velocities and tangential angles in log＇s cross section of Quercus mongolica,Pinus koraiensis,Abies nephrolepis and Populus ussuriensis.When tangential angles exceeded 36°,highest stress wave propagation velocities existed in log＇s cross section of Populus ussuriensis but lowest in log＇s cross section of Quercus mongolica.Finally,maximum velocities of in log＇s cross section of Quercus mongolica,Pinus koraiensis,Abies nephrolepis and Populus ussuriensis were 1 109.0,1 220.4,1 245.8,and 1 618.3 m·s-1,respectively.