CAJ | 학술논문

为了消除非白噪声环境激励在结构模态参数识别结果中产生的虚假模态，引入扩展状态模型，从状态空间方程的角度论证了虚假模态产生的原因；然后，针对一类具有典型性和代表性的（自相关函数在纵坐标轴附近一定范围内有非零值的）非白噪声环境激励信号，在传统随机子空间算法的基础上引入延时指标，建立延时随机子空间方法。数值算例表明延时随机子空间方法能够有效地剔除非白噪声环境激励在模态参数识别结果中产生的虚假模态，放宽了传统模态参数识别方法对环境输入的白噪声假设。
위료소제비백조성배경격려재결구모태삼수식별결과중산생적허가모태，인입확전상태모형，종상태공간방정적각도론증료허가모태산생적원인；연후，침대일류구유전형성화대표성적（자상관함수재종좌표축부근일정범위내유비령치적）비백조성배경격려신호，재전통수궤자공간산법적기출상인입연시지표，건립연시수궤자공간방법。수치산례표명연시수궤자공간방법능구유효지척제비백조성배경격려재모태삼수식별결과중산생적허가모태，방관료전통모태삼수식별방법대배경수입적백조성가설。
In order to eliminate spurious modes caused by non-white noise ambient inputs,an augmented state space model was introduced to explain how the spurious modes arise in the modal parameter identification of structures. For a kind of typical non-white ambient excitations,whose autocorrelation function values are nonzeroes near the vertical axis,the delay-index-based stochastic subspace method was proposed by introducing a delay index in the traditional stochastic subspace method.Numerical examples showed that this improved method can eliminate spurious modes due to non-white noise inputs the white noise assumption of ambient excitations in the traditional modal analysis methods.