NESI控制大跨度桥梁非线性颤振的有效性与鲁棒性OA

To enhance the nonlinear flutter performance of long-span bridges,the nonlinear energy sink-inerter(NESI)control method is proposed.Firstly,based on a two-degree-of-freedom bending-torsion coupled non-linear self-excited force model,the equations of motion for the fully coupled wind-bridge-NESI system are es-tablished.Then,a parameter optimization method for NESI is developed using the gradient-based optimiza-tion(GBO)algorithm.Subsequently,taking a section model of a long-span suspension bridge as an example,the sensitivity of NESI parameters to nonlinear flutter control effectiveness is analyzed.Finally,with nonlin-ear flutter control as the objective,the effectiveness and robustness of NESI optimized with consideration of structural and aerodynamic nonlinear effects are investigated.The results demonstrate that numerical predic-tions of structural responses obtained using the explicit fourth-order Runge-Kutta(RK4)method agree well with experimental values.The NESI device,designed through parameter optimization considering structural and aerodynamic nonlinearities,can significantly reduce nonlinear flutter amplitudes of a bridge and the stroke of the NESI mass block.The NESI exhibits excellent robustness against uncertainties in structural frequencies and damping ratios.