一种摩擦滑移组合隔震系统力学性能及应用分析

Mechanical Properties Combined Sliding and Application of a Isolation System

摩擦滑移隔震是一种较为常见的隔震加固形式,具有减震效果好、构造简单等优点,但由于其大震下隔震层位移偏大、震后残余变形大的缺点,从而限制了其应用发展。针对软土地基长周期木结构既有建筑隔震加固需求,基于摩擦滑移组合隔震性能,设计一种以弹性滑板支座为主,辅以少量厚层橡胶隔震支座及黏滞阻尼器的隔震系统,即主要通过摩擦滑移形成频域较宽的有效隔震能力,设置厚层橡胶支座减少隔震层震后残余变形,而黏滞阻尼器则用于降低隔震层最大位移。提出多水准隔震结构等效自振周期概念及计算方法,分析了此组合隔震系统的力学性能。分析表明,该方法取得了良好的隔震效果,验证了该组合隔震系统的有效性,对今后类似的隔震加固工程具有一定的参考价值。

Friction-sliding isolation system （FIS） is a common type of widely used isolation technique for building retrofitting, which has the advantages of better seismic response mitigation effects and simpler construction details. However,development of FIS is limited by its drawback of the large displacement of the seismic isolation layer under rare earthquakes with the significant residual post-earthquake deformations. A combined friction-sliding isolation system （CFIS） is designed based on the combined sliding isolation performnce to fit the requirements of retrofitted timber buildings on soft ground,which is mainly composed of elastic sliding bearings,with additional laminated thick rubber bearings （TLRs） and viscous dampers. A very good isolation efficiency of the elastic sliding bearings with wide range of frequency is proved, and the residual deformation and the maximum displacementof the isolation layer is considerably reduced respectively through TLRs and viscous dampers. The conception and calculation method of the equivalent natural periods of the isolated structure with CFIS under various seismic ground motions are proposed, and the mechanical properties of CFIS are analyzed. With good isolation efficiency of CFIS, this system will be of reference value for similar seismic isolation retrofit projects in the future.