SMA Strands-Laminated Rubber Compound Bearing And Its Seismic Isolation Behavior

In seismic isolation of structures, ordinary laminated rubber bearing and lead rubber bearing are widely used as isolation components. Due to low lateral stiffness of the ordinary laminated rubber bearing, excessive lateral shear deformation may cause the bearing unstable. The lead rubber bearing can not restore to its original phase after excessive lateral shear deformation, which may reduce the self-restoring capacity of the bearing.By employing super-elasticity property of shape memory strands is installed all-around the ordinary laminated rubber bearing as a supplement of restoring capacity of the bearing. This not only increases the lateral stiffness of the bearing, but also makes the bearing restore to its original phase after excessive lateral shear deformation and keep the bearing stable.In this dissertation, a SMA-laminated rubber compound bearing is developed and the seismic isolation behavior of the developed bearing is systematically investigated. This provides a scientific reference for engineering application and has important theoretical significance and engineering value. The main research work and creative achievements are included three aspects as following:(1) Development on SMA strands-laminated rubber compound bearing. Through test on mechanical behavior of SMA wire and SMA strand, the SMA strand is proved to have better super-elasticity property. Against the problem of low lateral stiffness and restoring capacity of the original laminated rubber bearing and employing the super-elasticity property of SMA material, the SMA strands are installed all-around the ordinary laminated rubber bearing, and a novel SMA strands-laminated rubber compound bearing is designed and developed.(2) Shaking table test on seismic isolation behavior of the SMA strands-laminated rubber compound bearing. Through comparison test on earthquake simulation shaking table, the influence of displacement amplitude on fundamental parameters, including equivalent lateral stiffness, maximum restoring force and equivalent damping ratio and so on, of seismic isolation behavior of the SMA strands-laminated rubber compound bearing in investigated. This verifies that the SMA strands-laminated rubber compound bearing has good seismic isolation behavior. (3) Study on seismic isolation behavior of structure based on SMA strands-laminated rubber compound bearing. Through numerical simulation and comparison analysis for seismic responses of a four-story frame structure in the three cases of without any seismic isolation bearing, with original laminated rubber bearings or with SMA strands-laminated rubber compound bearings, the developed SMA strands-laminated rubber compound bearing is further proved to have superior seismic isolation behavior.