Applications of Viscoelastic Damper to Jointed Structures for Seismic Mitigation

Some structures, such as dams, are built with contraction joints that might carry some small tensile stresses. Such joints are expected to open and close during an earthquake. That will cause stress redistributions during the opening and closing of the contraction joints. The repeated opening and closing of the contraction joints may deteriorate the joints and result in local failure of the concrete. In this paper, a new concept of the application of the viscoelastic damper to the contraction joint is proposed to decrease the cracks of the joints, and absorb the energy resulting from the earthquake. To analyze the behavior of the structure with added dampers, a new viscoelastic model, in good agreement with experimental results, and a new viscoelastic finite element formulation are presented. Numerical results have shown that the responses of jointed structures to earthquake loadings are significantly reduced. The size of the opening of the contraction joints, displacements of the structure, stress distributions in the structure and stress concentration around joints are also significantly reduced.