Study On Evaluation For Dynamic Strength Reliability Of Structures

The deficiency of dynamic strength always leads to problems of structural destruction and invalidation which widely exist in fields of aerospace, mechanical, construction and marine engineering. Therefore, how to evaluate the structural dynamic strength correctly becomes a major concern by designers. In this thesis, a combination of Monte Carlo finite element method (MCFEM) and maximum entropy method (MEM) is used to analyze the structural dynamic strength problem based on reliability analysis. An accurate, trusty and intuitionistic estimation of dynamic strength is obtained by numerical calculation using the Latin Hypercube Sampling. MCFEM is an important method used for strength reliability analysis. Its advantages are good applicability and simpleness. MEM is a method based on maximum entropy principle in information theory which can furthest make use of information of original data without special dealing. It has the advantages of high accuracy and good computational efficiency by considerating arbitrary order of moments.Firstly, basic theories of Monte Carlo numerical simulation method and MEM are briefly introduced. And then, the detailed procedures of Monte Carlo finite element - maximum entropy method (MFMM) are given in combination with Latin hypercube sampling technique. A numerical calculation program is developed and then used for analyzing structural dynamic strength reliability of a cantilever beam and a support structure. The MFMM results are compared with DMCS results. Numerical results indicate that the written program and analysis procedures are correct. It is also shown that MFMM has advantages of simpleness, good applicability, low computation effort and high accuracy.