Application study on mechanical property of the shape memory alloy for bridge bearings

Shape memory alloy (SMA) is provided with preferable damp capacity at pseudo-elasticity state, applying this property, a SMA re-centring damper is introduced by some scholars. In this paper, the new isolation system combining the above damper with laminated rubber bearing is proposed, so as to obtain preferable isolation character and re-centring capacity. To illustrate the feasibility and effectiveness of the proposed system, the following work is done: First, according the constitution model of SMA at pseudo-elasticity state the program is compiled, then the mechanical behavior of damper is simulated and the hysteretic curve is obtained. Based on the above, a linear restoring model for SMA re-centring damper is put forward. And then, the program based on the theory of story model for shear tape is compiled to conduct elasto-plastic time history analysis of practical structure examples, According to the results, the seismic response of structure is significantly reduced, and the fully re-centring capacity after earthquake is obtained by this isolation system. At last, the theory basis of SMA bridge bearings is provided for the further study and widely applied.