研究MR阻尼器对武汉天兴洲公铁两用斜拉桥主梁纵向列车制动响应智能控制的理论与应用的关键技术,此技术已获取多个国家发明专利授权。文中在获取列车制动引起的天兴洲大桥主梁节点上的作用力时程的基础上,建立了MR阻尼器对漂浮型铁路斜拉桥主梁和桥塔纵向列车制动响应智能控制的基本方程和仿真分析方法,提出效果明显优于"被动-开"控制的改进的固定增量半主动控制策略。与此同时,对天兴洲大桥应用的目前世界上出力最大的500kN磁流变液阻尼器的稳定性、耐磨损寿命要求、设计制作的关键技术以及性能试验进行了研究。并在正确识别500kN磁流变液阻尼器参数的基础上,对武汉天兴洲公铁两用斜拉桥主梁纵向列车制动响应的智能控制进行仿真设计。结果表明,MR阻尼器的智能控制能有效地抑制天兴洲大桥主梁和桥塔的纵向列车制动响应,以保证大桥的安全和正常使用。
The intelligent control for longitudinal vibration responses of the deck of the Wuhan Tianxingzhou highway-railway cable-stayed Bridge under train braking with magneto-rheological(MR) dampers is investigated.Based on the action force time histories on the bridge nodes subjected to train braking,the dynamic equation and simulating method for intelligent control of the longitudinal vibration responses of the deck of the floating-type railway cable-stayed bridge are established and a modified fixed incremental semi-active control strategy,the control effect of which is better than that of "passive-on" control,is proposed.The crucial technologies of design and fabrication and the performance test on the 500kN large-scale MR damper with the largest damping force are investigated.Based on identification of the mechanical parameters of 500kN MR damper,the longitudinal vibration responses of the deck of the Wuhan Tianxingzhou Bridge with MR dampers subjected to train braking are analyzed.Results show that the MR dampers can effectively mitigate the longitudinal responses of the deck of the Tianxingzhou Bridge under the train braking and train traffic excitation.