大跨桥梁振动的杠杆调谐质量阻尼器控制策略评价

根据建立的LT-TMD-结构系统的动力放大系数解析式,讨论了LT-TMD的动力特性(包括冲程).数值结果表明,LT-TMD和传统的TMD具有相同的控制有效性和冲程;然而,LT-TMD比传统的TMD具有更大的最优调谐频率比和更小的最优阻尼比.LT-TMD的关键优点是可通过移动支撑的位置来限制LT-TMD弹簧的静力和动力伸长而保持其控制有效性和冲程不变.鉴于此,LT-TMD可能是控制大跨桥梁振动的一种较好的策略.

Performance Assessment of Lever-type Tuned Mass Damper for Long-span Bridges

Employing the derived analytical expressions for the dynamic magnification factors of the lever-type tuned mass damper (LT-TMD) structure system, the performance assessment (including the stroke displacement) of the LT-TMD is carried out. The numerical results indicate that the LT-TMD may achieve the same effectiveness and stroke displacement as the tuned mass damper (TMD). However, the LT-TMD needs higher optimum tuning frequency ratio and lesser optimum damping ratio with reference to the TMD. A key advantage of the LT-TMD, compared to the TMD, is that the static stretching of the spring of the LT-TMD may be adjusted in accordance with the practical requirements through changing the locations of the support while maintaining the same effectiveness and stroke displacement as the TMD. In view of this, the LT-TMD may be a better choice for suppressing the vibrations of long-span bridges with the consequence but not permitting a large static stretching of the spring in practical implementation.