为了解决模型修正过程中修正目标众多和测量信息有限的矛盾，提出了多重子步模型修正方法(MSMUM)，先进行误差定位，再实现参数修正，把复杂的模型修正过程分步实现。利用子结构技术，使结构模型在整体上仅包含有限数目的子结构，对各子结构所对应的超级单元的刚度参与系数进行识别来实现误差定位，通过建立测量信息与待修正参数间的代数方程来修正误差定位后子结构内部构件的参数。数值算例表明，建立的模型修正方法有效可靠。利用建立的多重子步模型修正方法对润扬大桥南汊悬索桥桥塔模型进行了修正。

Basing on substructure analysis, original research on multi-stage model updating method (MSMUM) is presented to reduce the uncertainties in traditional model updating process. The kernel philosophy of the multi-stage model updating method is used to update a complicated FE model with multi steps, i. e. firstly localize the model errors and then update the error parameters. Comparing with the computed results, it is shown that the error localization methods and the parameter updating methods developed here are fine. As a case study, the model of the Runyang Nancha suspension bridge tower is updated with the MSMUM. Comparing the updated FE model here with the updated model using traditional updating method, it could be concluded that the multi-stage updating method is more effective.