The Theoretic And Numerical Analysis Of Damage Identification Of The Plane Truss

The inverse problem in engineering mechanics is a hot research focus in engineering and mechanics since 1980s. In recent decades, various methods of damage identification have been put up for problems in engineering structure such as steel corrosion, fatigue crackles and prestresse loose. These methods include damage identification based on vhbration analysis, X-ray methods and various artificial intelligence methods. Each method has its advantages and disadvantages due to the complexity of damages.The experimental data for damage identification consists of two major types in mechanics, i.e., static data and dynamic data. In static data, point displacement measurement data is more easily available and more accurate. Meanwhile, in dynamic data, structural natural frequency measurement data is more easily available and more accurate, especially low-rank natural frequency.Because static strength testing bears the advantage of convenient and economic operation, it has better vigor in terms of economy. At the same time, it bears the disadvantage of long testing time, and its data cannot reflect the overall capacity. Compared to static strength teeing, dynamic strength testing bears the advantages of no damage to structure units, easy acquisition of data and overall reflection of capacity. In recent years, many scholars have done researches on structure damage assessment using vibration parameter and put up relevant calculation methods. However, it also has the defect of weaker measurement precision of the data, e.g., type of vibration.Based on the above situation and relevant documents, this paper discusses damage identification of plane truss applying data of relative measurement precision (static displacement and natural frequency). To be specific, this paper explores how to identify damage with limited use of local damage testing instruments using fewer static data. Based on relevant documents, the paper also discusses the method of damage identification based on natural frequency changes. Having compared the math models of various damage identifications and other methods, the author of the paper puts up a new math model of damage identification which both demands easier calculation and keeps considerable precision at the same time.