SMA-负刚度双曲面隔震装置的减震性能研究

Aseismic performance of SMA-based negative stiffness isolation bearings

虽然SMA减隔震支座可以提高桥梁的自复位能力,但与普通减隔震支座相比,会增大下部结构的内力响应。为解决这一问题,拟提出一种新型SMA负刚度双曲面隔震装置。该装置由SMA索提供恢复力,由两个曲面反向的摩擦摆支座提供负刚度,由滑块和上、下钢板间的摩擦提供耗能能力。理论推导及有限元分析结果表明,该减震装置既可为桥梁提供自复位能力,又可在减小桥梁位移响应的前提下,部分减小SMA隔震桥梁结构体系的内力响应。

Compared with traditional isolation bearings,superelastic shape memory alloy(SMA)-based isolation bearings can improve the re-centering capability of bridges,but they result in higher forces in the substructures.A novel SMA-based negative stiffness isolation bearing was proposed to reduce the forces.It was composed of SMA-cable,providing the re-centering capability,and a friction pendulum bearing with inverted surfaces,providing negative stiffness to reduce the transmitted forces.The theoretical and finite element analyses of the bearing were conducted.It turns out that the novel isolation bearing can not only provide re-centering capability,but also reduce the internal force response of bridges when they are subjected to earthquakes.