C. W. Bert2016-01-142016-03-302016-01-142016-03-302001-11-01Bert, C. W. (2001). Improved Equation for Shear Modulus Using Four-Point Ring-Twist Test Data. Journal of Thermoplastic Composite Materials, 14(6), 489-497. doi: 10.1106/gng0-lr9b-ffkb-rv13http://hdl.handle.net/11244/24895There are numerous test-specimen configurations for determining the static shear modulus of composites. Selection of specimen configuration depends primarily on product component configuration. Two-ring specimens in use are the split-ring twist specimen and the four-point-loading ring-twist specimen. The latter is more advantageous, since it uses an intact ring. However, reported validation tests on aluminum rings showed a large error in predicted shear modulus. The present paper provides an improved analysis that takes into account the tilting of the cross section on the loading bar.en-USResearch Article10.1106/gng0-lr9b-ffkb-rv13false