Background:
Structural damage identification is a very important subject in the field of
civil, mechanical and aerospace engineering according to recent patents. Optimal sensor placement
is one of the key problems to be solved in structural damage identification.
Methods:
This paper presents a simple and convenient algorithm for optimizing sensor locations for
structural damage identification. Unlike other algorithms found in the published papers, the optimization
procedure of sensor placement is divided into two stages. The first stage is to determine the
key parts in the whole structure by their contribution to the global flexibility perturbation. The
second stage is to place sensors on the nodes associated with those key parts for monitoring possible
damage more efficiently. With the sensor locations determined by the proposed optimization
process, structural damage can be readily identified by using the incomplete modes yielded from
these optimized sensor measurements. In addition, an Improved Ridge Estimate (IRE) technique is
proposed in this study to effectively resist the data errors due to modal truncation and measurement
noise. Two truss structures and a frame structure are used as examples to demonstrate the feasibility
and efficiency of the presented algorithm.
Results:
From the numerical results, structural damages can be successfully detected by the proposed
method using the partial modes yielded by the optimal measurement with 5% noise level.
Conclusion:
It has been shown that the proposed method is simple to implement and effective for
structural damage identification.
