【摘要】 为实时获得精确的大型结构模态参数 ,以便于结构的实时安全监测和抗风、抗震研究 ,在传统的 ITD时域分析方法的基础上 ,提出利用三次样条函数微分方法从结构位移得到结构的速度和加速度响应 ,从而进行模态识别的新方法 ,克服了传统 ITD方法人工选择参数的不利影响 .通过对虎门大桥的模态分析结果表明 :利用该法所得模态数和精度与 FFT相比 ,更接近于有限元数值分析结果 ,可用作结构的实时模态分析和在线监测更多还原

【Abstract】 A new modal analysis method was put forward to on\|line extract precise modal parameters form long structures. The method is very important to study the anti\|wind, aseismatic and real time monitoring of the structure. Based on traditional ITD modal analysis, this method got the velocity and acceleration response by using the cubic spline function differential method from displacement response. As a result, the disadvantage caused by artificial selection of parameters was overcame. The modal analysis results of a bridge from this method and FFT show that this method is closer to FEM and can be used to structural on\|line monitoring and real time modal analysis.更多还原