ABSTRACT
EXTENDED ABSTRACT: Two-blade bridge piers represent today an innovative solution to optimize the structural behavior of long viaducts subjected to seismic actions (Biondini 2001, Calzona & Bontempi 2001). In fact, a proper design of the structure provides a correct transmission of vertical loads to the foundation structures and the possibility to allow horizontal displacements without the use of kinematics mechanisms. Due to the particular configuration of the pier (a rigid box section in the bottom part and two flexible blades at the top connected with the viaduct deck), the structural behavior can be achieved only using refined analysis formulations and effective numerical tools. In particular, during the nonlinear response, the shear effects are very important and can govern the structural behavior. Nonlinear models have to be able to consider the shear damaging with sufficient accuracy otherwise, the numerical response would be affected by heavy errors. In addition, uncertainties on material characteristics can affect the numerical response. To handle these important uncertainties involved in the problem, the use of probabilistic or fuzzy approaches can be suitable.
