Relationship of Stress Wave- and Static Bending-Determined Properties of Four Northeastern Hardwoods

Authors

  • Stephen J. Smulski

Keywords:

Nondestructive evaluation, stress wave, stress wave modulus, characteristic impedance, hardwood, mechnical properties

Abstract

Stress wave modulus, velocity, and characteristic impedance of small, clear, straight-grained beams of sugar maple, yellow birch, white ash, and red oak were correlated with static bending MOE and MOR. Stress wave velocity increased in direct proportion to the square root of MOE for each species individually and for all four taken as a group. No meaningful relationship between wave velocity and specific gravity was found. Stress wave modulus was most strongly correlated with MOE, and characteristic impedance most strongly correlated with MOR for all species whether considered individually or as a group. Characteristic impedance, stress wave modulus, and MOE are nearly equally well correlated with MOR apparently because of their mutual relationship with specific gravity. No consistent differences in the relationships between stress wave- and static bending-determined properties were found for ring- versus diffuse-porous species.

References

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Published

2007-06-28

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Research Contributions