Study On Optimal Fish Swarm Algorithm For Damage Identification Of Space Frame Structure

In the field of civil engineering,engineering structures in the long term,use of the term,the interaction of various unfavorable factors may lead to the damage structure,in extreme cases even cause catastrophic accidents,if can be realized effectively for structural damage identification,it can be early warning to the security problem structure,to avoid the disaster therefore,the significance of research on damage identification of the major structure,has been highly concerned about the domestic and foreign scholars and engineering circles.Although the traditional detection method can realize the nondestructive testing of the structure,but most of them belong to the local diagnosis method,it is difficult to diagnose the whole structure.This paper improves the fish swarm algorithm by combining genetic algorithm,applies the optimized fish swarm algorithm to structural damage identification,and establishes a damage identification method that can achieve global diagnosis for the structure.Based on the global damage diagnosis of structural system,the main achievements are obtained as follows:1.Combined with the advantages of fish swarm algorithm,such as high initial parameter setting,high convergence speed and high convergence accuracy,a new optimization fish swarm algorithm is established,which has low requirement for initial parameters,late convergence speed and convergence accuracy.2.The optimization fish swarm algorithm is applied to the field of structural damage identification,and a global damage identification method is established,which can identify structural damage location and identify structural damage degree.3.Taking damaged continuous beam structure as an example,the three aspects of parameter optimization,fish swarm algorithm,genetic algorithm and classic fish swarm algorithm are compared in terms of parameter sensitivity,convergence speed and convergence accuracy,which verify the superiority of the improved fish swarm algorithm.4.The optimization fish swarm algorithm is applied to study the identification problem of single spatial structure with single damage and multiple damage(2,3 and 4 damage respectively).The effectiveness of the optimized fish swarm algorithm is verified.On this basis,the damage identification problem of multi-layer frame with damage is further discussed,and satisfactory results have been obtained.This method provides an effective way for the damage identification of complex structures.The conclusion of this paper can be used as a reference for engineering applications.