Structural Damage Identification And Experimental Study Based On Improved Chimp Optimization Algorithm

Building structures are constantly exposed to various environmental factors,including temperature fluctuations,chemical corrosion,and earthquakes.Over time,damage will inevitably accumulate,leading to a decrease in the structural bearing capacity and posing a threat to the overall safety of the structure.The study and development of structural damage identification methods and technologies are of great significance to the safe and reliable operation of existing buildings.Aiming at the problems of low identification accuracy,high misjudgment rate and poor noise immunity of the structural damage identification method,this paper introduces the chimp optimization algorithm into the field of structural damage identification,and proposes an improvement strategy for the chimp optimization algorithm and objective function.The specific research contents include:(1)A structural damage identification method based on chimp optimization algorithm(ChOA)is proposed by constructing a traditional objective function using frequency and mode shape.Using the particle swarm optimization algorithm and the chimp optimization algorithm,numerical simulation is carried out on simply supported beam under different cases,and the feasibility of the chimp optimization algorithm in the field of structural damage identification is verified.(2)Aiming at the insufficient optimization ability of the chimp optimization algorithm under multiple damage cases,the paper proposes a hybrid whale-chimp optimization algorithm(W-ChOA)based on the Sobol sequence.First,three typical high-dimensional test functions are used to verify that W-ChOA has better global convergence ability than ChOA.Secondly,the numerical simulation results of the double-layer rigid frame show that compared with ChOA,W-ChOA has faster convergence speed and higher identification accuracy in the process of structural damage identification.(3)To solve the problem of insufficient damage identification accuracy of the traditional objective function under high noise conditions,this paper proposes an improved objective function based on flexibility,mode shape and trace sparse constraint.Through the numerical simulation of simply supported beam and double-layer rigid frame,it is verified that the structural damage identification method based on W-ChOA and improved objective function has the advantages of high identification accuracy,less unit misjudgment and strong noise resistance.(4)To verify the feasibility of applying the method proposed in this paper to the actual structure,damage identification experiment is carried out on simply supported beam.Firstly,different damage conditions are set by symmetrically slotting on both sides of the beam unit.Secondly,the acceleration sensor and dynamic signal test and analysis system are used to obtain the modal information of the simply supported beam.Finally,the simply supported beam damage is identified based on the modal information.It can be seen from the experiment results that the method proposed in the paper can effectively identify the preset damage of simply supported beam,and has a good application prospect in practical engineering.