초기 비틀림/굽힘을 가진 복합구조체의 미소 역학적 빔 모델링

Abstract

Along with the increased knowledge and fabrication Techniques of multifunctional microstructures, research on the usage of composite structures with them in designing and manufacturing future helicopter blades have received considerable and consistent attention in the past few decades. Unlike the published work invoking the prismatic beam modeling, the present work proposes a new micro-mechanical approach for analyzing and predicting complicatedly mechanical behaviors of composite structures with initial twisted and curved configurations. At first, the three-dimensional heterogeneous elasticity problem is compactly formulated in an intrinsic form which admits initially twisted and curved effects. By taking advantage of smallness of beam-geometric and microstructure-heterogeneous parameters, the variational asymptotic method is then used to split the original three-dimensional problem into a linear three-dimensional micromechanical analysis on the microscopic level and a nonlinear one-dimensional beam analysis on the macroscopic level, respectively. Furthermore, the formulation obtained from the present approach is transformed into a generalized Timoshenko-like beam model as a reasonable compromise between efficiency and accuracy for modeling the initial twisted and curved beams. As the primary validation, a few examples available in the literature are used to demonstrate the capability and accuracy of this new model.