Estimating lumber properties with acoustic-based technologies—Part 2: Ultimate tension stress estimation from time- and frequency-domain parameters
Year: 2020
Type: article
Abstract: This research article summarizes results from Part 1 of a study designed to examine the use of advanced signal processing techniques with acoustic-based lumber assessment technologies to evaluate the MOE and ultimate tension stress (UTS) of structural lumber. In Part 1 of this research, a mathematical model of acoustic wave behavior in an idealized specimen is derived using fundamental mechanics. In Part 2, wave behavior is examined experimentally in a series of 38 × 38 × 2438-mm wood specimens. The specimens vary considerably in visual character. Several of the specimens are, from a visual assessment, clear of naturally occurring defects such as knots. Conversely, strength-reducing defects such as knots are visible in several specimens. The presence of naturally occurring defects can affect acoustic waves in a variety of ways. A few examples include altering wave speed, changing the wave travel path, and/or converting the wave from longitudinal waves to shear waves or back through mode conversion. These alterations can cause wave behavior to deviate from the behavior observed in clear wood specimens. Deviations are observable in both time and frequency domains. From the differences, parameters are identified which improve estimation of UTS.
Source: Wood and Fiber Science
Language: English
Subfield: Building and Construction
Field: Engineering
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W3097248189