声-超声技术评价兴安落叶松规格材的抗弯性质  

Evaluation of Bending Properties of Larch Dimension Lumber with Acousto-Ultrasonic Technique

作　　者：张训亚[1] 姜笑梅[1] 吕斌[1] 殷亚方[1] 

机构地区：[1]中国林业科学研究院木材工业研究所,北京100091

出　　处：《林业科学》2014年第10期94-98,共5页Scientia Silvae Sinicae

基　　金："十一五"国家科技支撑计划课题(2006BAD18B07)

摘　　要：测量落叶松规格材的波速、峰值电压、时间形心和频率形心等声-超声参数,以及气干密度、抗弯弹性模量和抗弯强度等物理力学性质,研究声-超声参数、气干密度、动态弹性模量等与抗弯性质之间的相关性。为了探索利用声-超声技术预测落叶松抗弯性质的可行性,分别以动态弹性模量和声-超声参数及气干密度为自变量,建立预测其规格材抗弯性质的回归模型。结果表明:所有的声-超声参数、气干密度与抗弯弹性模量均在0.01水平显著相关,峰值电压、频率形心、气干密度与抗弯强度在0.01水平显著相关。利用气干密度、峰值电压和波速3个参数为自变量建立的抗弯弹性模量和抗弯强度的预测模型的相关性(决定系数r2分别为0.83和0.66)与传统的超声波方法(以动态弹性模量为自变量建立的抗弯弹性模量和抗弯强度预测模型,r2分别为0.80和0.34)相比,模型的预测能力显著提高。利用声-超声技术能够较好地预测落叶松规格材的抗弯力学性质,特别是抗弯强度。Acousto-ultrasonic（ AU） technology was used to evaluate bending properties of air-dried dimension lumber of Chinese larch（ Larix gmelinii）. Some AU parameters including wave velocity,peak voltage,time-centroid and frequencycentroid were measured. The air-dried density and bending properties of static modulus of elasticity（ MOE） and modulus of rupture（ MOR） were also measured. The relationships between AU parameters and density and MOE,MOR were analyzed and the prediction regression equations of bending properties based on AU parameters and air-dried density were built. The results showed that the relationships between all the AU parameters and air-dried density and MOE,as well as the relationships between peak voltage,frequency-centroid and air-dried density and MOR were significant at 0. 01 level.Better regression results for MOE and MOR prediction can be achieved with air-dried density,peak voltage and wave velocity as independent variables with r^2= 0. 83 and r^2= 0. 66 respectively,compared with traditional ultrasonic technique with dynamic modulus of elasticity（ DMOE） as independent variable with r^2= 0. 80 and r^2= 0. 34 respectively. The study indicated that acousto-ultrasonic technology can be used to predict the bending mechanical properties of larch dimension lumber better than ultrasonic wave technology especially modulus of rupture.

关 键 词：落叶松 声-超声参数 气干密度 动态弹性模量 抗弯弹性模量 抗弯强度 

分 类 号：S781[农业科学—木材科学与技术]