DAMAGE IDENTIFICATION IN FRAME STRUCTURES BY MODEL UPDATING

摘要

A damage identification method is proposed for frame structures based on finite element model updating techniques. An objective function is defined as minimizing the sum of differences between the experimental and analytical modal data, which is set as a nonlinear least-squares problem with bound-constrains. Such minimization problem is solved by the trust-region approach in order to make this optimization process more robust and reliable. For the sake of application of this damage identification method into real structures, both the expansion and weighting of the original objective function are studied as well. A numerical two-story portal frame structure and a lab three-story building frame structure are both adopted to evaluate the efficiency of the proposed method. Some important issues related are also discussed in detail.