Creep - Relaxation Behavior of Cable - Stayed Bridges and its Prediction

Abstract

It is essential for design and maintenance of cable-stayed bridges to know long-term behavior due to visco-elastic deformation of cable strands, sockets, concrete members and ground settlement at the supports. This paper deals with a methodology to predict the long-term change of bridge geometry, particularly change of cable forces. First the full-scale long-term tension tests of various cable systems are introduced and the visco-elastic deformation of the cable strands andsockets are summarized. Secondly the method to determine the visco-elastic constants of cables and the finite element visco-elastic analysis together with the Laplace transformation are proposed. Analytical results by the proposed method are compared to the site measurement values and good agreement is made.