Damage Identification Of Random Structures Based On Recursive Stochastic Finite Element

The purpose of these research works is to develop a theoretical method for the damage assessment of structures after the literature' method compare analysis, which could be function only need the lower modes, and this method can be used in damage identification in civil engineering. Hence exploring research works on 5 aspects have been done around the purpose.1. Recursive Stochastic Finite Element Method (RSFEM) researchSeveral examples show that compared with perturbation stochastic finite elements method based on Taylor expansion, the results obtained utilizing RSFEM are found to be more close to those of Monte-Carlo simulation in relatively large range of random fluctuation and even if only taking the first four items of nonorthogonal polynomials expansion, effectiveness of RSFEM is still well.2. Damage identification of random structures based on RSFEMA new probabilistic approach for damage identification is given in this paper. The structural damage index is defined as a change in stiffness, which indicates the amount of stiffness reduction or increase for each structural element. After the statistic characters of structural damage index are obtained using RSFEM, the statistic damaged structural parameters can be given. Several simple numerical examples are used to state the new probabilistic approach to damage identification.3. A high precise element in analyzing structural damage identification researchIn this paper, a rectangular element with high precision is presented. It is suited to analyzing various structures, especial in frames or shear-walls or infilled panel aspects, and make up the deficiencies of other elements for plane problems. A simple numerical example is used to state its effectiveness.4. Damage identification of a clip beam and a one-floor frameRandom FE model with statistic undamaged structural parameters and measured eigenpair including noise is used to assess the structural damage index. Structuraldamage was characterized by a change in stiffness only. The approach accounts for structural variability in eigenpair being due to experimental errors in the test process. The results obtained utilizing RSFEM are found to be more close to those of Monte-Carlo simulation in relatively large range of random fluctuation5. Damage identification of a three-floor frame based on two-step damagediagnosis methodsIn this paper, two-step damage diagnosis methods is summarized .The problems that damage diagnoses of large and complex structures face on are presented .The thinking and methods of two-step approaches in existence are listed, and the investigative direction required is pointed out . Damage identification of a three-floor frame states that the damage identification of random structures based on RSFEM method is effective. All this can provide reference for damage diagnoses of large and complex structures.