Abstract
The strength of an industrial composite such as a .ber-reinforced plastic falls between those of .ber and plastic matrix. While the ligament is composed of collagen fascicles in a matrix whose stiffness is almost negligible, the bulk ligament is stiffer than the fascicles that compose it; we will call this nature of ligament as inverse characteristics. To insight into the mechanism of the inverse characteristic, we developed two kinds of kinematic model of ligament composed of a bundle of fascicles by taking the ligament's hierarchy structure into account; one is a discrete type of spring model and the other is a continuous type of hyper elastic model. We incorporated a fascicle.s kinematic non-uniformity along it and mechanical interaction between fascicles due to matrix into the models. First we created the discrete model so as to duplicate three typical phases seen in a stress-strain curve of ligament, namely the toe, linear and failure phases. Then we created the continuous model under the conditions of .nite deformation and incompressibiliy, which are inherent in the ligament. Simulations were performed using the above two models, thereby obtaining the results which reproduced the above-mentioned inverse characteristics.
