A time-domain system identification technique with optimum number of finite elements

The authors are trying to develop a system identification technique to identify a structure at the local element level without using any input excitation information and using only a limited amount of output response information. It is a time domain finite-element based algorithm. Acceleration time histories are recorded at node points, and the records are integrated successively to obtain the velocity and displacement time histories. Because it is a finite element-based algorithm, the total number of elements or node points could be numerous, and it may not be practical or economical to collect the acceleration response at every node point. The optimum number of elements or node points required to identify a structure is a major concern, and is the subject of this paper.