Electric resistance tomography and stress wave tomography for decay detection in trees—a comparison study

PeerJ

article

Xiaoquan Yue¹  Lihai Wang²  James P. Wacker³  Zhiming Zhu¹ 

[1] College of Transportation and Civil Engineering, Fujian Agriculture and Forestry University of China;College of Engineering and Technology, Northeast Forest University;Forest Service, Forest Products Laboratory, United States Department of Agriculture

关键词: Stress wave tomography;    Mass loss;    Electric resistance tomography;    The severity of decay;    Nondestructive techniques in live trees;   

DOI  :  10.7717/peerj.6444

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

BackgroundTo ensure the safety of trees, two NDT (nondestructive testing) techniques, electric resistance tomography and stress wave tomography, were employed to quantitatively detect and characterize the internal decay of standing trees. Comparisons between those two techniques were done to make full use of the individual capability for decay detection.MethodsEighty trees (40 Manchurian ash and 40 Populus simonii) were detected, then wood increment cores were obtained from each cross disc trial. The Dt, which was defined as the value determined by the mass loss ratio of each wood core, was regarded as the true severity of decay. Using ordinary least-squares regression to analyze the relationship between Dt and De (De was defined as the severity of decay determined by electric resistance tomography) and between Dt and Ds (Ds was defined as the severity of decay determined by stress wave tomography).ResultsThe results showed that both methods could estimate the severity of decay in trees. In terms of different stages of decay, when Dt < 30%, De had a strong positive correlation with Dt (R2 = 0.677, P < 0.01), while, when Dt ≥ 30%, Ds had a significant positive correlation relationship with Dt (R2 = 0.645, P < 0.01).ConclusionElectric resistance tomography was better than stress wave tomography for testing in the early stages of decay, while stress wave tomography can be used effectively in the late stage of decay. It is suggested that each technique can be used in the practice of internal decay testing of standing trees based on decay stages and operating conditions.

【 授权许可】

CC BY