基于鲁棒性能的超大跨桥梁主动控制面颤抖振控制原理与方法

This proposal focuses on the problem that the effectiveness of traditional aerodynamic measures and robustness of active aerodynamic measures cannot effectively meet the wind resistant demand for super-long-span bridges, and studies the active control surface system in order to enhance its engineering reliability. The proposal applies theoretical analysis, wind-tunnel test, numerical simulation and statistical analysis methods to explore a precisely mechanical model for deck-surface system and a geometrical design method of surface itself based on robust performance, to investigate a robust control algorithm adapting wind variation and hysteresis effects of actuation systems and a quantitative evaluation method based on reliability theory to evaluate robust performance of control surface. This proposal tries to solve two scientific problems, such as generation mechanism of self-excited force acting on control surface when vibrating with large amplitudes and the relationship between the intrinsic properties of control system and wind velocity. The aim of this proposal is to establish an active control method based on robust performance for flutter and buffeting suppression of super-long-span bridge, to reveal statistic characteristics of self-excited force and interference force induced by large-amplitude vibration of control surfaces, to clarify the dependency of robust control law on wind speed, and to identify critical factors influencing robust performance of active control surface system and its application prospects. The prospective achievement of this proposal will contribute to further understand the reliability of active control surface for flutter and buffeting suppressing, and will provide technical reference for wind-induced vibration suppression of super-long-span bridges in sea-crossing and island-linking projects.

针对传统气动措施的有效性和主动气动措施的鲁棒性均不能有效满足超大跨桥梁抗风需求的问题，以主动控制面为研究对象，以提高控制面工程可靠性为目标，采用理论分析、风洞试验、数值模拟和统计分析相结合的研究手段，探索主梁-控制面体系精细化力学模型，研究基于鲁棒性能的控制面几何尺度设计方法及考虑作动力滞后效应并适应风速全过程的颤抖振控制算法，寻求基于可靠度理论的控制面鲁棒性能定量评价方法，着重解决大振幅条件下控制面自激力形成机理及规律、控制系统特性与风速依存关系等关键科学问题。项目预期将建立基于鲁棒性能的超大跨桥梁颤抖振控制方法，揭示控制面大幅振动条件下自激气动力和干扰气动力的数理特征，阐明控制面颤抖振控制律与风速的依存关系，进一步明确影响控制面鲁棒性能的敏感因素及其工程应用的可行性，研究成果将为主动控制面颤抖振控制可靠性的准确认知奠定基础，为跨海连岛工程中超大跨桥梁风振控制问题提供技术参考。

针对传统气动措施的有效性和主动气动措施的鲁棒性均不能有效满足超大跨桥梁抗风需求的问题，以主动控制面为研究对象，采用理论分析、风洞试验、数值模拟和统计分析相结合的研究手段，探索主梁-控制面体系精细化力学模型，研究基于鲁棒性能的控制面几何尺度设计方法及考虑作动力滞后效应并适应风速全过程的颤抖振控制算法，寻求基于可靠度理论的控制面鲁棒性能定量评价方法。通过研究发现：（1）振动翼板大幅振动（扭转振幅为±10°）确实会对主梁气动力产生较为严重的干扰，但压力脉动卓越频率成分占比在10%以内；（2）控制面大幅振动时，控制面上自激力非线性效应主要体现在自激力幅值上的倍频现象和相位漂移现象，且D=0.25H时自激力相位偏离了理论值约14°，而D=1.00H情况下约为7.5°。（3）考虑到颤振控制时控制面的振动幅度基本与主梁扭转振幅相当，主梁-控制面气动力模型中主梁上的自激力可不考虑干扰效应，控制面上的自激力可采用修正的Theodorsen函数，或者在控制算法中考虑这部分相位偏差。（4）控制面自身颤振临界风速随控制面自由长度和宽度的增大而减小，而抖振竖向位移根方差随控制面自由长度和宽度的增大而增大，建议控制面宽度取主梁宽度的10%。（5）当采用考虑控制面运动滞后和自激力相位滞后并采用Schur降阶后的最优控制算法时，控制率（增益系数）随风速变化并不显著，且相同的翼板转角的增益系数所能获得的最大控制效果基本呈现随气动干扰影响的增强而下降的趋势，但变化程度并不十分剧烈。（6）迎风侧、背风侧控制面扭转运动振幅在[0, 1.0]范围内变化，控制面相位偏离最优相位角±20°时，颤振临界风速下降比例均10%在之下。通过研究揭示了控制面大幅振动条件下自激气动力和干扰气动力的数理特征，建立了考虑控制面自激力相位漂移的主梁-控制面模型，阐明了控制面颤抖振控制律与风速的依存关系，进一步明确影响控制面鲁棒性能的敏感因素，研究成果将为主动控制面颤抖振控制可靠性的准确认知奠定基础。