|Table of Contents|

[1] Li Shu, Xu Zhaodong, Wang Shaojie, et al. Modal macro-strain identification from operationalmacro-strain shape under changing loading conditions [J]. Journal of Southeast University (English Edition), 2016, 32 (2): 219-225. [doi:10.3969/j.issn.1003-7985.2016.02.015]

Modal macro-strain identification from operationalmacro-strain shape under changing loading conditions()

Journal of Southeast University (English Edition)[ISSN:1003-7985/CN:32-1325/N]

2016 2
Research Field:
Computer Science and Engineering
Publishing date:


Modal macro-strain identification from operationalmacro-strain shape under changing loading conditions
Li Shu1 Xu Zhaodong1 2 Wang Shaojie1 Wu Zhishen3
1School of Civil Engineering, Southeast University, Nanjing 210096, China
2Key Laboratory of Concrete and Prestressed Concrete Structures of Ministry of Education, Southeast University, Nanjing 210096, China
3International Institute for Urban Systems Engineering, Southeast University, Nanjing 210096, China
macro-stain/distributed strain fiber Bragg grating(FBG) operational modal analysis(OMA) operational deflection shape(ODS) transmissibility
To develop modal macro-strain(MMS)identification techniques and improve their applicability in a continuous health monitoring system for civil infrastructures, the concept of operational macro-strain shape(OMSS)and the corresponding identification method are proposed under unknown ever-changing loading conditions, and the MMS is then obtained. The core of the proposed technique is mainly based on the specific property that the macro-strain transmissibility tends to be independent of external excitations at the poles of the system and converges to a unique value. The proposed method is verified using the experimental data from a three-span continuous beam excited by an impact hammer at different locations. The identified results are also compared with the commonly used methods, such as the peak-picking(PP)method, the stochastic subspace identification(SSI)method, and numerical results, in the case of unknown input forces. Results show that the proposed technique has unique merits in accuracy and robustness due to its combining multiple tests under changing loading conditions, which also reveal the promising application of the distributed strain sensing system in identifying MMS of operational structures, as well as in the structural health monitoring(SHM)field.


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Biographies: Li Shu(1984—), male, graduate; Xu Zhaodong(corresponding author), male, doctor, professor, zhdxu@163.com.
Foundation items: The National Natural Science Foudation of China(No.51578140), the Natural Science Foundation of Jiangsu Province(No.BK20151092), Scientific Innovation Research of College Graduates in Jiangsu Province(No.CXZZ12_0108).
Citation: Li Shu, Xu Zhaodong, Wang Shaojie, et al. Modal macro-strain identification from operational macro-strain shape under changing loading conditions[J].Journal of Southeast University(English Edition), 2016, 32(2):219-225.doi:10.3969/j.issn.1003-7985.2016.02.015.
Last Update: 2016-06-20