Load Identification Method Based On Interval Parameter Structure

Among the problems of load identification in engineering structures,due to the limitations of the technical level and the level of experimental measurement,there often exist various uncertainties in the structural parameters.These uncertainties lead to large deviation between the load identification results and the nominal values,seriously affect the accuracy of load identification problems.And,because of the cost of measurement,the uncertainty information of the engineering structure is often poor,especially when studying the inversion system which contains a lot of uncertainties.Therefore,it is very important to study the problem of indentified load of structure under poor information.In recent years,with the continuous development of deterministic structural load identification methods,the research on the identification of uncertain structural loads has become a hot topic in the field of mechanical inverse problems.However,most of the current research focuses mainly on the identification of uncertain structural loads based on probabilistic models.Probabilistic methods are difficult in practical engineering applications.Therefore,it is of great practical value to develop an identification method for uncertain structural loads based on non-probabilistic interval models.In this paper,we mainly study the situation when the uncertain parameters appear in the problem of load identification and load identification.Using the interval parameter model,the uncertain structure is described as the interval parameter structure and the load identification research.The specific research content mainly includes: 1.Based on the analysis of the harmonics of the periodic excitation to generate the Fourier series and the least square method of the solution of the overdetermined equations,an inverse harmonic balance method is proposed to identify any periodic excitations carried by the engineering structure and use multiple periodic excitation pairs.The proposed method was verified.2.Based on the frequency domain method and the first-order Taylor expansion method,the load identification of the uncertain structure under the simple harmonic excitation was performed.The influence of the interval parameter variation on the recognition result was discussed.3.Using the interval analysis method based on Taylor expansion,a non-probabilistic interval method for identifying random load of uncertain structures is proposed.The influence of interval parameter variation on the recognition results is discussed.