Development of sliding bearing system for multi-level earthquake motions

本研究的目的是发展桥梁的滑动支座体系，以应对多层次地震。集成滑动支座系统使用橡胶支座板来支撑主要载荷，如恒载和活载，并使用滑块缓冲系统通过摩擦阻尼来减少地震反应。任何单一的承重装置都几乎不可能同时满足日常一般使用和减少地震反应的功能要求。此外，对于单个装置，地震运动的强度范围非常宽。然而，将一个具有日常功能的设备与设计用于满足各种地震反应范围的设备结合起来是可能的。多级缓冲器串联使用两种不同类型的缓冲器。两个缓冲层之间的塞子在大于一级地震的荷载下会断裂。在一级地震时，位移响应将受到限制，不与相邻的梁发生碰撞。在这种情况下，该设备起到关节保护的作用。在2级地震时，止震器发生断裂，使梁在长自然周期内发生大位移振动。这将导致大量的能量被摩擦吸收在滑动界面的轴承。在数值模拟中考虑了阀塞的破坏概率。结果表明，塞杆强度的变化不影响整个桥梁体系的响应。这样，从现有系统开发的新系统将扩大集成滑动轴承的应用。

The aim of this study is to develop the sliding bearing system for bridges to meet the multi-level earthquakes. The integrated sliding bearing system utilizes rubber bearing plates to support the main loads, such as dead loads and live loads, and a slider-buffer system to reduce seismic response by frictional damping.It is almost impossible for any single bearing device to satisfy the functional requirements for both everyday general use and the reduction of the seismic response. Furthermore, the strength range of the earthquake motions is very wide to meet for a single device. However, it might be possible to combine one device that has everyday functionality with devices designed to meet the various range of the seismic responses.A multi-level buffer utilizes two different types of buffer in tandem. The stoppers between the two buffers would break under loads greater than Level-1 earthquakes. During Level-1 earthquakes, the displacement response would be limited not to collide with adjacent girders. In this case, the device functions as a joint protector. During Level-2 earthquakes, the stopper would break, enabling the girder to vibrate with large excursion in long natural period. This would result in large amounts of energy being absorbed by friction at the sliding interface of the bearings.The destruction probability of the stoppers was taken into account in the numerical simulations. The results showed that the variation in the strength of the stoppers did not affect the response of the whole bridge system. In this way, new systems developed from the current system would expand the application of integrated sliding bearings.