기능경사재료 변단면 보에서 축방향 탄성계수의 공간적 불확실성에 의한 응답변화도 평가 = Evaluation of Response Variability of Functionally Graded Material Beam with Varying Sectional Area due to Spatial Randomness in Elastic Modulus along Axial Direction

다국어 초록 (Multilingual Abstract)

In this paper, a scheme to evaluate the response variability for functionally graded material (FGM) beam with varying sectional area is presented. The randomness is assumed to appear in a spatial domain along the beam axis in the elastic modulus. The functionally graded material categorized as composite materials, however without the drawbacks of delamination and occurrence of cracks due to abrupt change in material properties between layers in the conventional composite materials. The functionally graded material is produced by the gradual solidification through thickness direction, which endows continuous variation of material properties, which makes this material performs in a smooth way. However, due to difficulties in tailoring the gradients, to have uncertainty in material properties is unavoidable. The elastic modulus at the center section is assumed to be random in the spatial domain along the beam axis. Introducing random variables, defined in terms of stochastic integration, the first and second moments of responses are evaluated. The proposed scheme is verified by using the Monte Carlo simulation based on the random samples generated employing the spectral representation scheme. The response variability as a function of correlation distance, the effects of material and geometrical parameters on the response variability are investigated in detail. The efficiency of the proposed scheme is also addressed by comparing the analysis time of the proposed scheme and MCS.

참고문헌 (Reference)

1 노혁천, "탄성계수의 불확실성에 의한 복합적층판 구조의 응답변화도" 한국전산구조공학회 21 (21): 335-345, 2008

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