نوع مقاله : مقاله پژوهشی
1 دانشیار، دانشکده مهندسی عمران، دانشگاه سمنان
2 دانشجوی دکتری، دانشکده مهندسی عمران، دانشگاه سمنان
3 دانشیار، دانشکده مهندسی عمران، دانشگاه پورتو (FEUP)، پورتو، پرتغال
عنوان مقاله [English]
Undoubtedly, bridges have substantially effect in metropolitan areas and are usually built to connect between two roads in order to decrease traffic. Pounding, is one of the important parameters to design different bridges as this structures should be controlled during seismic excitation to provide safety conditions in order to organize and support unpredictable situations. During very strong earthquake, bridges may experience large horizontal relative displacement, which may lead to pounding if sufficient gap size is not considered between adjacent slabs of bridge. Insufficient separation distance is naturally caused to collide between two slabs and, subsequently, stiffness of bridge is decreased and finally, collapse is occurred. In order to determine impact force and also absorption energy during collision, many researchers have demonstrated different theories and also suggested various equations by using impact velocity before and after impact. In this study, special element is used between two slabs to determine impact force and a new equation of motion is mathematically presented to calculate impact damping ratio focusing on coefficient of restitution.