隔振桥梁列车制动响应的仿人自适应控制

Human-simulated adaptive control of the train braking response on the isolated bridge

针对桥梁被动支座因隔振耗能能力受限的问题,提出了结构参数可调的小尺度磁敏支座的设计及测试建模方法,利用相似关系结合有限元法建立了列车制动下全尺度桥的磁敏支座隔振系统模型,通过对顺桥向制动下桥梁隔振系统受到的冲击振动特征进行状态划分,以墩顶剪力与梁体位移为主要目标、兼顾梁体加速度指标,设计出列车制动作用下桥梁隔振系统缓冲减振的仿人自适应控制算法.用Maltab对列车制动下顺桥向隔振控制系统进行仿真计算.结果表明:列车不同制动停止位置对隔振系统的影响明显,在第三跨中制动停止时系统响应最为剧烈;采用仿人自适应控制的磁敏支座智能系统,使梁体位移最大值减少了53.9%,墩顶剪力峰值减少了34.4%,综合隔振率降低51.8%,缓解了被动支座难以同时降低力和位移响应的矛盾,提升了桥梁结构隔振耗能的能力.

Considering the problem that vibration energy dissipation capacity of passive bridge bearings is limited,a small scale magnetorheological elastomer bearing（MRB）was designed,tested and modeled,whose structural parameters are adjustable.The similar relations and finite element method（FEM）were carried out to model and optimize full scale isolation system of railway bridge.Based on the model above,a human-simulated adaptive control（HSAC）algorithm for isolating the bridge vibration under the impact of train braking was designed by classifying longitudinal vibration characteristics into several statuses and choosing shear force peak of pier top,the displacement of beam and acceleration of beam as indicator.Then the simulation of longitudinal vibration control system under the condition of train braking was achieved by Matlab.The result indicates that different train with braking stop positions significantly have effect on the vibration isolation system,and the system response is the most drastic when the train stops at the third cross-span.The MRB system with HSAC can reduce the displacement of beam,shear force peak of pier top and integrated vibration isolation ratio by53.9%,34.4%and 51.8%respectively.The problem that the force and displacement of passive bearings decreases at the same time is ameliorated,and the vibration energy dissipation capacity of bridge structure is also enhanced.