Improved Structural Analysis Technique for Orthogonal Weave Carbon-Carbon Materials

Abstract

An approximate technique is presented that enables one to use two-dimensional axisymmetric solid computer codes for the analysis of three-dimensi onal rectangularly orthotropic materials fabricated into axisymmetric shapes and loaded axisymmetrically. The technique consists of modifying the polar coordinate constitutive relations to accomodate a rectangularly orthotropic material Specifically the proposed constitutive modification: accounts for the transverse orthotropy by including Gxy in the equations as an independent variable; degenerates to the transversely isotropic relations for Ex = Ey = E and Gxy = Ex/2(l + vxy); and accurately predicts the stresses in a rotating and thermally loaded rectangularly orthotropic disk whereas analyses restricted to the assumption of transverse isotropy can lead to significant errors.