Mathematical modeling of suspension bridges

Since the collapse of Tacoma Narrows Bridge in 1940, scientists try to find out and clear up the real cause of this disaster. The main problem seems to be the fundamental nonlinearity of a dynamical system describing a behavior of a suspension bridge which results in its nonunique solvability. We would like to explain several approaches to modeling of periodic oscillations of suspension bridges and state a short survey of known results in this field, concerning especially the existence of a unique solution.