A Study Of Interval Analysis And Application To Static/Dynamic Characteristics Of The Structure With Uncertain Parameters

There is a variety of uncertainties in the actual project, and the uncertainty ofsystem parameters is a vital branch of uncertainties. By interval analysis method, theuncertainty of system could be transfered to the natural feature of system and theresponse of system in the calculation.This thesis studied the interval factor method, based on the midpoint of the intervalvalue, and which has represented the problem in the actual calculation. So the improvedinterval factor method,based on interval width of the interval factor, was put forwardnear zero point. In order to improve the efficiency of interval factor method, two simpleapproach were proposed for dealing with the interval factor, and comparing the effect bythe results of two examples. Then the improved interval factor method with thesub-interval and interval finite element perturbation method was used to researching theeigenvalue and frequency function analysis of structures with uncertain parameters.Given two methods to solve how to get the interval factor matrix. First, when theinterval matrix is diagonalizable matrix, the interval factor matrix could be efficientlyacquired and not lose the uncertainty of system. Then, for the other general intervalmatrix, its interval factor matrix also could be acquired by the element-by-element(EBE)idea which could effectively solve the coupling of interval factor problem, such ascoupling of the systematic stiffness.This thesis uses the improved sub-interval finite element perturbation method toanalyze static displacement response and dynamic response of the truss structure. Andstudying the uncertainty of different parameters how impacts on natural characteristicsand the response of the truss system. And given the rapid estimation methods of theuncertainty of natural characteristics. Finally, based on mechanical testing experimentsof carbon fiber reinforced composites, studying the uncertainty of frequencys of thespecial anisotropic laminates and antisymmetric angle laminates under the uncertaintyof elastic constants. Analysised the impact to the uncertainty of natural frequency at thedifference laying angles.