The main features of the FRF of long span Runyang Bridge, which has 1 024 dimensions, can be extracted by 27 or 17 principal components, and the reconstruction error is acceptable.

• 对于大跨斜拉桥（润扬长江大桥北汉斜拉桥）的1024维频响函数可以仅用27个（或17个）主元来提取其主要特征，精度可满足工程需要。