Concept and analysis of a low-cost energy dissipater with partially self-centering mechanism

Abstract

To achieve a good self-centering ability in the ‘rocking’ connection, the applied initial prestressed force of the post-tensioned tendons should be high enough to provide sufficient restoring force for the connection. However, a too high initial prestress level of the post-tensioned tendons weakens the deformation capacity of the connection. In answer to this problem, a low-cost and easy-construction bamboo-shaped energy dissipater with parallel elastic spring (PS-SBED) was proposed in this paper, which aims at sustaining good self-centering ability, obtaining enough energy dissipation capacity and improving deformation capacity. The proposed energy dissipater is featured as partially self-centering mechanism which was proved through theoretical and numerical ways. Explicit expressions for the self-centering ability and energy dissipation capacity of the PS-SBED were derived based on the theoretical hysteretic model. The effects of the stiffness, initial deformation and application conditions of the spring on the performance of the PS-SBED were evaluated based on parametric studies through validated numerical model. The bearing capacity of the PS-SBED was positively affected by the spring's stiffness and initial deformation. The residual deformation of the PS-SBED could be effectively reduced by the application of the elastic spring, compared with the energy dissipater without spring, but the energy dissipation capacity of the PS-SBED was not affected by the application of the spring. The application of the PS-SBED was able to increase the bearing capacity and improve the self-centering ability of the ‘rocking’ connection with low initial prestress level, which proved the effectiveness of the PS-SBED.