Based On Model Structure Fuzzy Damage Identification

Damage identification technology based on the structural dynamic characteristics is new methods developed in recent years, many scholars do a lot of reasearch works in this field and a lot of research achievements are obtained, and some research results have been successfully applied to the practical engineering. But for large civil engineering, due to components production or structure construction error, the uncertainty alway existed in structure parameters,these uncertainties may be stochastic or fuzziness,even be random fuzziness.but during sturcture analysis,we always take the structure parameters as a certainty,it make the analysis results cannot reflect the practical structure,even the damage identification result based on dynamic characteristics will be effected.so it is necessary to consider the uncertainty of the parameters during the structure design and analysis.This paper first present a brief introduction of the status of the damage identification method.Secondly, The change value of strain model is taken as damage index to identify the strcuture damage.The results suggest that the strain model is a good index to identificate structure damage.The strain model is taken as characters to establish the data of the standard and using the fuzzy membership to identificate sturcture damage.By considenring the fuzziness of the structure paremeters,dimension and the loading,this paper established the stiffness and mass matrix,Rayleigh Method is employed to obtain the sturcture frequency.Though a truss,the effort of those fuzzy on structure dynamic characteristic is analysed.The question mentioned above is the direct question of vibration,this paper also study the inverse eigen problem,the method of inverse eigen problem is used to identificate structure stiffness,through a example,it is showed that the feasibility of this method.At last,this method is used into a practial engineering to verified its feasibility and reliability.