Introducing compression platen misalignment in single fiber transverse compression analytical models

Abstract

Analytical models of Single Fiber Transverse Compression Tests (SFTCTs) are commonplace for the identification of a fiber’s apparent transverse elastic modulus $E_T$ by inverse method. Compression platen misalignment however, has been shown to induce important identification errors due to the change in the platen-fiber contact surface compared to the parallel platen configuration. Nevertheless, methods to minimize this misalignment experimentally are sparse in the literature and no existing analytical models take it into consideration. In this paper the development of such a model is presented, which accounts for the angle around the fiber’s pitch axis, named ”tilt” angle. The predictions of this analytical model are shown to closely match the results of an equivalent Finite element model. Using force and displacement data resulting from this Finite element analysis, along with fiber’s material and geometric properties and the value of the tilt angle, the proposed analytical model produces very low identification errors of $E_T$, independently of the tilt angle. The proposed model can thus be used to reliably identify a fiber’s transverse elastic modulus even for SFTCTs where a tilt angle is present.