Seismic performance of precast concrete walls with replaceable steel slit connections for high-rise buildings

In recent years, the use of demountable and reparable precast concrete buildings in high seismic regions has received special attention. However, very limited studies have been devoted to investigating demountable walls with ductile steel connections for high-rise buildings. In this regard, the present paper proposes precast concrete walls with replaceable steel slit connectors for mitigating seismic demands of high-rise building structures. In addition to connecting the walls to the adjacent beams, these steel slit connectors play the role of seismic dampers. Also, in the proposed system, rocking joints are introduced at the base of the columns to reduce the structural damage to the boundary elements. To evaluate the structural performance of the proposed system, two types of micro- and macro-numerical models are developed and validated by experimental data. First the cyclic behavior of the system is examined for a 1-story frame. As the cyclic loading results indicate, the nonlinear behavior is concentrated in the steel slit dampers while the main structural elements remain undamaged. Therefore, for the optimal distribution of the steel slit dampers along the height of multi-story frames, a cost-effective and practical optimization method is presented based on the uniform damage distribution concept. According to this optimization method, three reference frames of 10, 15 and 20-story equipped with the proposed system are designed and subjected to the time history loadings. For each reference frame, three models with different damper distributions are compared with a conventional structural wall model. Time history analyses demonstrate that the proposed models experience less inter-story drifts (up to 34%), floor accelerations (up to 82%) and residual drifts (up to 86%) compared to the conventional structural wall models.