Measurement of Poisson's ratios for yellow-poplar.

Abstract

Longitudinal/tangential, longitudinal/radial, tangential/radial, and radial/tangential Poisson's ratios for yellow-poplar (Liriodendron tulipifera) were determined using the white light speckle technique in experimental mechanics called the Digital Image Correlation Technique (DICT). Average values were found to compare well with other literature values where available ; however, DICT allowed for calculation of Poisson's ratios from multiple measurements spanning the entire specimen rather than from one or two points per specimen. It was further discovered that for yellow-poplar, Poisson's ratio is not a constant during the loading process, but decreases with increasing load.