中文摘要：

诊断结构损伤时往往需要完备的自由度信息,然而在实际工程中很难测量到结构的全部自由度信息.本文通过一简支桥梁结构有限元模型的数值模拟,利用O＇ Callahan改进缩聚法与Kidder动态扩阶法进行自由度匹配,获取结构所需的完备自由度信息,在此基础上用模态应变能法较好地实现了测试信息不完备情况下的简支桥梁结构损伤识别.该方法简单可靠,可为实际工程应用提供参考.

英文摘要：

Mismatching between the degrees of freedoms （DOFS） of the measurement model and those of the finite element model is a difficult problem when damage detection technique is used to the actual project. Through a numerical simulation of the simply supported beam element model, freedom is matched by using improved condensation method of O＇ Callahan reduction and Kidder dynamic expansion to obtain complete freedom, then based on these, the modal strain energy damage identification method can realize the simply supported bridge structure damage identification under the incomplete test information. The method is simple and reliable, which can provide reference for the practical engineering application.