STUDY ON ADDITIONAL MASS TO THE CABLE-STAYED BRIDGE AS A COUNTERMEASURE AGAINST GREAT EARTHQUAKE

Abstract

Though it is necessary even for already constructed bridges to improve their antiseismic property according to the Specifications for Highway Bridges 1996, there are many cases in which reinforcement is almost impossible. The tower of cable-stayed bridge responds to transverse great earthquake is one of such cases.
In this study, we made an attempt to reduce the response of tower by means of additional mass to the cables, which changed the interaction among girder, tower and cables. Because there were innumerable combinations of additional mass distributed to the cables, the best decision was made by some optimization techniques. Some numerical examples showed that the response could be reduced to sufficient level.