【摘要】 采用Lagrange方程建立了磁流变式调谐液柱阻尼器(MR-TLCD)与桥梁单自由度扭转耦合结构的动力学模型,依据试验数据把磁流变液阻尼器简化成Bingham模型并采用等效线性化处理。在简谐荷载激励情况下,在时域和频域内优化了随输入电流值变化的4种截面MR-TLCD的参数;在随机风荷载激励情况下,进一步评估了优化后的MR-TLCD对桥梁风致扭转振动的控制效果。结果表明:这4种MR-TLCD都存在相应的最小平均动力放大系数比,且截面面积越大对应的最优电流值越大,平均动力放大系数比越小;扭转角位移峰值减小了43.9%,扭转加速度减小了41.1%。更多还原

【Abstract】 Lagrange equation was adopted to establish the coupled structure dynamic model of magnetorheological tuned liquid column damper (MR-TLCD) and bridge single degree-of-freedom torsion. The MR damper was simplified to the Bingham model based on experimental data,and its nonlinear item was approximated by the equivalent linearization. The cases of parameters for four different cross-sections of MR-TLCD with change of current input were optimized in time domain and frequency domain excited by harmonic load. The wind-induced torsional vibration control effect of bridge with MR-TLCD was further evaluated by random wind-induced load. The result demonstrates that there is the least mean dynamic magnification factors ratio (MDMFR) for each section,moreover,the greater cross-section is,the higher current value is and the less MDMFR is. The peak value of torsional angular displacement and torsional acceleration were reduced by 43.9% and 41.1% respectively.更多还原