Task I: Output-only System Identification and FE Model Updating
Task Definition
Participants are suggested to carry out system identification with the output only field measurement data and update the reduced model with particular methods. A special session in the 5th World Conference on Structural Control and Monitoring (WCSCM5, 12-14 July 2010, Tokyo, Japan) is being organised by Dr. YQ Ni and Dr. Y Xia. Participants of the special session please provide the following information in the paper:
1) Methodology and data used in system identification;
2) Results of system identification (natural frequencies, mode shapes, damping ratios, and so on);
3) Objective function,
weighting matrix
and any constraints in model updating;
4)
Updating parameters in the mass and
stiffness
matrices;
5) Computer model and CPU time consuming;
6) Number of modes or data used;
7) Differences of natural frequencies between the measurement and the updated model prediction;
8) MAC values of mode shapes between the measurement and the updated model prediction;
9) Other relevant parameters
Special issue on
this problem will also be organi
Field Measurement
Ambient vibration measurement data during one construction stage are provided here for this Task. The acceleration, wind direction, wind speed and ambient temperature were recorded during a period of 24 hours (18:00 pm 19th Jan. 2010 to 18:00 pm 20th Jan. 2010). The participants can determine the data period, their own algorithms and parameters in system identification. Description of the measurement can be downloaded at here (PDF, 670 KB). All of the measurement data can be downloaded in one ZIP file at here (ZIP, 420 MB); or downloaded individually:
Acceleration Data: 1st hour (ZIP, 16.3 MB); Acceleration Data: 2nd hour (ZIP, 16.3 MB);
Acceleration Data: 3rd hour (ZIP, 16.3 MB); Acceleration Data: 4th hour (ZIP, 16.3 MB);
Acceleration Data: 5th hour (ZIP, 16.3 MB); Acceleration Data: 6th hour (ZIP, 16.3 MB);
Acceleration Data: 7th hour (ZIP, 16.3 MB); Acceleration Data: 8th hour (ZIP, 16.3 MB);
Acceleration Data: 9th hour (ZIP, 16.3 MB); Acceleration Data: 10th hour (ZIP, 16.3 MB);
Acceleration Data: 11th hour (ZIP, 16.3 MB); Acceleration Data: 12th hour (ZIP, 16.3 MB);
Acceleration Data: 13th hour (ZIP, 16.3 MB); Acceleration Data: 14th hour (ZIP, 16.3 MB);
Acceleration Data: 15th hour (ZIP, 16.3 MB); Acceleration Data: 16th hour (ZIP, 16.3 MB);
Acceleration Data: 17th hour (ZIP, 16.3 MB); Acceleration Data: 18th hour (ZIP, 16.3 MB);
Acceleration Data: 19th hour (ZIP, 16.3 MB); Acceleration Data: 20th hour (ZIP, 16.3 MB);
Acceleration Data: 21st hour (ZIP, 16.3 MB); Acceleration Data: 22nd hour (ZIP, 16.3 MB);
Acceleration Data: 23rd hour (ZIP, 16.3 MB); Acceleration Data: 24th hour (ZIP, 16.3 MB);
Wind direction data: 24 hours (ZIP, 13.5 MB); Wind speed data: 24 hours (ZIP, 14.3 MB;
Temperature data: 24 hours (TXT, 19 KB)
Finite Element Model
Based on the design drawings of the TV tower, a fine 3D finite element (FE) model with total DOFs of 505164 has been established in ANSYS. Based on this fine model, a reduced 3D beam model with DOFs of 185 is constructed and provided here to the research community. Researchers are free to carry out their own FE model updating studies and other Tasks. Description of the reduced model and the procedures of reduction can be found at here (PDF, 503 KB). The global stiffness matrix, global mass matrix, and the element matrices of the reduced model can be downloaded here (MAT, 597 KB, version 6.5).
Description of the TV Tower and the SHM system can be referred to this web or a Journal paper:
Ni, Y. Q., Xia, Y., Liao, W. Y., and Ko, J. M., (2009), “Technology Innovation
in Developing the Structural Health Monitoring System for