An energy approach for the analysis of the mechanical response of three-dimensional elastic curvilinear fibers is proposed. Equivalent tangent stiffnesses and compliances are defined relating generalized displacements with applied loads in terms of both direct and mutual moduli. Many numerical
applications are developed in order to investigate about the influence of fiber geometric parameters, addressing also
large-displacement cases by means of an incremental formulation. Finally, considering planar fibers, explicit relationships for tangent and secant equivalent along-the-chord elastic moduli are
deduced, leading to useful and direct expressions for the analysis and the design of composite materials reinforced by curvilinear elastic fibers
