An Adaptive Chromosome Technique of Genetic Algorithms to Identify Structural Damage

In order to identify the damage location and extent of large-scale civil engineering structures, an adaptive chromosome technique of genetic algorithms (GA) is proposed. The technique utilizes real number coding to design chromosomes, each damage element is described by such a gene pair that includes damage element number and damage extent. Then, the individual chromosome will increase one pair of gene in the next cycle of GA. It will not present new damage elements unless the number of gene pairs of chromosomes exceed the real number of damage elements. The actual damage element would be coincided for the converged chromosomes of adjacent iteration steps of GA, which is used to decide damage locations and damage extents. The main advantage of the method is that the length of individual chromosome is only decided by the number of damage elements, but nothing to do with the total number of structure elements. Thus, it reduces the number of design genes and makes the GA converge fast. At last, a numerical example of 10-bar truss shows that the method can accurately identify the damage location, with less error of damage extent estimation.