Nondestructive Methods for Detecting Defects in Softwood Logs
Nondestructive Methods for Detecting Defects in Softwood Logs

Author: Kristin C. Schad

Publisher:

Published: 1996

Total Pages: 16

ISBN-13:

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Wood degradation and defects, such as voids and knots, affect the quality and processing time of lumber. The ability to detect internal defects in the log can save mills time and processing costs. In this study, we investigated three nondestructive evaluation techniques for detecting internal wood defects. Sound wave transmission, x-ray computed tomography, and impulse radar were used to examine white spruce and balsam fir logs. Computed tomography resulted in the highest resolution for voids, knots, and high moisture content areas, but at a very high price. Both sound wave transmission and impulse radar were able to detect large voids and areas of degradation, and these techniques showed some sensitivity to very knotty logs. None of the methods was able to detect small pockets of decay. The use of radar requires an experienced operator because of the difficulty of interpreting the data.

Nondestructive Characterization and Imaging of Wood
Nondestructive Characterization and Imaging of Wood

Author: Voichita Bucur

Publisher: Springer Science & Business Media

Published: 2013-03-14

Total Pages: 361

ISBN-13: 3662089866

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This book on the Nondestructive Characterization and Imaging of Wood by Professor Voichita Bucur is truly the most outstanding reference on the subject ever written. Since the origins of mankind, wood has played a key role in the history of humans and other living creatures, ranging from provision of life from trees giving air, heat, light, and food to nourish their bodies to structures to protect them from the elements. Wood has also played a key role in one of the world's primary religions. Nondestructive diagnostics methods have long found application in medi cal practice for examination of the human body in order to detect life threatening abnormalities and permit diagnosis to extend life. Nondestructive testing has been used for many years to insure the safety of machinery, air craft, railroads, tunnels, buildings and many other structures. Therefore, it is timely for a treatise, like the present one, to be written describing how wood can be characterized without employing destructive test methods. Since wood is so valuable to mankind, it is important to know the latest methods to nondestructively characterize wood for all practical applications.

Monthly Catalog of United States Government Publications
Monthly Catalog of United States Government Publications

Author: United States. Superintendent of Documents

Publisher:

Published: 1980

Total Pages: 1268

ISBN-13:

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February issue includes Appendix entitled Directory of United States Government periodicals and subscription publications; September issue includes List of depository libraries; June and December issues include semiannual index

Efficient Utilization of Red Maple Lumber in Glued-laminated Timber Beams
Efficient Utilization of Red Maple Lumber in Glued-laminated Timber Beams

Author: John J. Janowiak

Publisher:

Published: 1995

Total Pages: 394

ISBN-13:

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The feasibility of utilizing cant-sawn hardwood lumber, which would not usually be desired for furniture manufacture, was studied for the manufacture of structural glued-laminated (glulam) timber. Two red maple beam combinations were evaluated: (1) a glulam combination designed with E-rated lumber in 25 percent of the outer laminations (top and bottom) and No. 3 grade lumber in 50 percent of the center laminations and (2) a wide-width glulam combination with laminations made from nominal 2- by 4- and 2- by 6-in. No. 2 grade lumber laid edge-to-edge having staggered end joints (termed 2 by 4/2 by 6 glulam combination). Test results of 42 red maple glulam beams showed that it was feasible to develop structural glulam timber from cant-sawn lumber. The glulam combinations made from E-rated lumber exceeded the target design bending stress of 2,400 lb/in2 and met the target modulus of elasticity (MOE) of 1.8 Ã 106 lb/in2. In addition, the 2 by 4/2 by 6 glulam combination exceeded published design stresses for vertically laminated bending strength, MOE in both the horizontally and vertically laminated orientations, and horizontal shear stress in the vertically laminated orientation. Based on the results of the 2 by 4/2 by 6 glulam combination, it was determined that edge gluing the laminations to form wide-width lumber is not required to achieve targeted strength and stiffness levels. Data analysis showed that ASTM D3737 procedures developed for softwood species accurately predict beam stiffness and provide conservative bending and horizontal shear strength estimates for red maple glulam beams. Also, it was shown that results from ASTM D143 shear-block tests could be used to accurately predict horizontal shear strength of 2 by 4 and 2 by 6 red maple glulam beams.

Ground Penetrating Radar Theory and Applications
Ground Penetrating Radar Theory and Applications

Author: Harry M. Jol

Publisher: Elsevier

Published: 2008-12-08

Total Pages: 545

ISBN-13: 0080951848

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Ground-penetrating radar (GPR) is a rapidly developing field that has seen tremendous progress over the past 15 years. The development of GPR spans aspects of geophysical science, technology, and a wide range of scientific and engineering applications. It is the breadth of applications that has made GPR such a valuable tool in the geophysical consulting and geotechnical engineering industries, has lead to its rapid development, and inspired new areas of research in academia. The topic of GPR has gone from not even being mentioned in geophysical texts ten years ago to being the focus of hundreds of research papers and special issues of journals dedicated to the topic. The explosion of primary literature devoted to GPR technology, theory and applications, has lead to a strong demand for an up-to-date synthesis and overview of this rapidly developing field. Because there are specifics in the utilization of GPR for different applications, a review of the current state of development of the applications along with the fundamental theory is required. This book will provide sufficient detail to allow both practitioners and newcomers to the area of GPR to use it as a handbook and primary research reference.*Review of GPR theory and applications by leaders in the field*Up-to-date information and references*Effective handbook and primary research reference for both experienced practitioners and newcomers

Nondestructive Evaluation of Wood
Nondestructive Evaluation of Wood

Author: Forest Service (U S )

Publisher: Government Printing Office

Published: 2015

Total Pages: 176

ISBN-13: 9780160928871

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Nature's engineering of wood through genetics, wind, and weather creates a wide variability in wood as a material. Consequently, manufacture and users of wood products are frequently frustrated in dealing with the forest resource. Manufacturers sometimes argue that wood is difficult to consistently process into quality products because of the wide range of properties that exist in this raw material. Users of wood products can be equally frustrated with the performance variability found in finished products. Nondestructive evaluation (NDE) technologies have contributed significantly toward eliminating the cause of these frustrations. NDE technologies have been developed and are currently used in lumber and veneer grading programs that result in engineered materials that have consistent well-defined performance characteristics. This brief volume explores some of the processes that are used to manufacture wood, including green wood technology and provides a bit of history to wood production and its uses too. Other products that may interest you from the US Forest Service can be found at this link: https://bookstore.gpo.gov/agency/819