“…On the other hand, when the beam deflection is positive everywhere in the area of joint, then the mechanical properties are equivalent to those of the undamaged joint. Note that, on one hand, such kinds of dynamic behavior bring the model into a class of distributed vibrating systems with nonsmooth nonlinearities, which are quite difficult to analyze (see, e.g., Chen and Shaw, 1996;Chati et al, 1997;Butcher, 1999;Jiang et al, 2004;Andreaus et al, 2007;Vestroni et al, 2007;Butcher and Lu, 2007;and Pilipchuk, 2009). On the other hand, it will be shown shortly that the corresponding characteristics of a nonlinear dynamic response can be employed for damage detection in joints.…”