Effect of Temperature on Acoustic Evaluation of Standing Trees and Logs: Part 2: Field Investigation

Authors

  • Shan Gao
  • Xiping Wang
  • Lihai Wang
  • R. Bruce Allison

Keywords:

Acoustic velocity, ambient temperature, logs, wood temperature, standing trees

Abstract

The objectives of this study were to investigate the effect of seasonal temperature changes on acoustic velocity measured on standing trees and green logs and to develop models for compensating temperature differences because acoustic measurements are performed in different climates and seasons. Field testing was conducted on 20 red pine (Pinus resinosa) trees and 10 freshly cut red pine logs at a 45-yr-old plantation stand in Arena, WI. Acoustic velocities of the red pine trees and logs and the ambient temperatures were monitored for 12 consecutive months. Results indicated that ambient temperature had a significant effect on acoustic velocities of trees and logs in winter when temperatures were below the freezing point. Acoustic velocities increased dramatically as ambient temperature dropped to below 0°C, but the increase became less significant when the temperature decreased to below -2.5°C. Above the freezing point, acoustic velocities were less sensitive to ambient temperature changes. From a practical standpoint, acoustic velocities of trees and logs measured at different climates and seasons can be adjusted to a standard temperature if measurements are conducted well above or well below freezing temperatures. However, measurements conducted around freezing temperatures could cause complications in making temperature adjustments. Users should avoid conducting field acoustic testing when wood temperature is around the freezing point.

References

ASTM (2003) D 4442-92. Standard test methods for direct moisture content measurement of wood and wood-base materials. American Society for Testing and Materials, West Conshohocken, PA.nBarrett JD, Green DW, Evans JW (1989) Temperature adjustments for the North American in-grade testing program. Pages 27-38 in DW Green, BE Shelley, and HP Vokey, eds. Proc In-Grade Testing of Structural Lumber. Forest Products Society, Madison, WI.nBodig J, Jayne BA (1982) Mechanics of wood and wood composites. Van Nostrand Reinhold Company, Inc., New York, NY. 712 pp.nCarter P (2011) Real-time measures of wood quality - transition from research to application. Pages 34-39 in Divos F, ed. Proc of the 17th International Nondestructive Testing and Evaluation of Wood Symposium, September 14-16, 2011, Sopron, Hungary. University of West Hungary, Sopron Hungary.nCarter P, Briggs D, Ross RJ, Wang X (2005) Acoustic testing to enhance western forest values and meet customer wood quality needs. Pages 121-129 in CA Harrington and SH Schoenholtz, eds. Productivity of western forests: A forest products focus. Gen Tech Rep PNW-GTR-642. USDA For Serv Pacific Northwest Research Station, Portland, OR.nChauhan SS, Walker JCF (2006) Variation in acoustic velocity and density with age, and their interrelationships in radiata pine. For Ecol Mgmt 229:388-394.nGao S, Wang X, Wang L, Allison RB (2012) Effect of temperature on acoustic evaluation of standing trees and logs: Part 1—Laboratory investigation. Wood Fiber Sci 44(3):286-297.nGerhards CC (1982) Effect of moisture content and temperature on the mechanical properties of wood: An analysis of immediate effects. Wood Fiber Sci 14(1):4-36.nGrabianowski M, Manley B, Walker JCF (2006) Acoustic measurements on standing trees, logs and green lumber. Wood Sci Technol 40:205-216.nGreen DW, Evans JW (2008) The immediate effect of temperature on the modulus of elasticity of green and dry lumber. Wood Fiber Sci 40(3):374-383.nHarris P, Petherick R, Andrews M (2002) Acoustic resonance tools. Pages 195-201 in Proc 12th International Symposium on Nondestructive Testing of Wood, August 9-21, 2011. University of California, Berkeley, CA.nHuang CL (2000) Predicting lumber stiffness of standing trees. Pages 173-179 in F Divos, ed. Proc 12th International Symposium on Nondestructive Testing of Wood, September 13-15, 2000, Sopron, Hungary. University of West Hungary, Sopron, Hungary.nKubler H, Liang L, Chang LS (1973) Thermal expansion of moist wood. Wood Fiber Sci 5(3):257-267.nMora CR, Schimleck LR, Isik F, Mahon JM Jr., Clark A III, Daniels RF (2009) Relationships between acoustic variables and different measures of stiffness in standing Pinus taeda trees. Can J For Res 39:1421-1429.nSilins U, Lieffers VJ, Bach L (2000) The effect of temperature on mechanical properties of standing lodgepole pine trees. Trees (Berl) 14:424-428.nWang X (1999) Stress wave-based nondestructive evaluation (NDE) methods for wood quality of standing trees. PhD dissertation, Michigan Technological University, Houghton, MI. 187 pp.nWang X (2011) Fundamentals of acoustic measurements on trees and logs and their implication to field application. Pages 25-33 in F Divos, ed. Proc 17th International Nondestructive Testing and Evaluation of Wood Symposium, September 14-16, 2011, Sopron, Hungary. University of West Hungary, Sopron, Hungary.nWang X, Carter P, Ross RJ, Brashaw BK (2007a) Acoustic assessment of wood quality of raw forest materials—A path to increased profitability. Forest Prod J 57 (5):6-14.nWang X, Ross RJ, Carter P (2007b) Acoustic evaluation of wood quality in standing trees. Part I, Acoustic wave behavior. Wood Fiber Sci 39(1):28-38.nWang X, Ross RJ, McClellan M, Barbour RJ, Erickson JR, Forsman JW, McGinnis GD (2001) Nondestructive evaluation of standing trees with a stress wave method. Wood Fiber Sci 33(4):522-533.n

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Published

2013-01-10

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Research Contributions