Stiffness identification under uncertain blast loading

We develop a finite element-based time-domain system identification algorithm which will identify structural parameters at the local element level without using input excitation information and with limited output response information. The proposed method has no restriction on types of input forces to be used to excite a structure. Blast loading and the uncertainty associated with modeling it are specifically addressed. The efficiency and accuracy of the algorithm are verified using several examples. For verification purposes, both noise-free and noise-included output response measurements are considered. The results indicate that the proposed method identifies the structural parameters at the element level very well.