Experimental study of frequency responses in a beam structure supported with nonlinear stiffness is investigated in this paper. The test rig consists of a linear cantilever rectangular beam with its free end held between two thin identical beams. It can generate the different nonlinear supports in the end of the uniform beam by inserting steel rulers into the ends of the thin beams, which results in the different pre-deformation and the drift of the static balance point. We found in the results that, as the pre-deformation and the amplitude of excitation changed, the uniform beam’s dynamic characteristic shifts between soft, hard and linear stiffness. Theoretical analysis shows that pre-deformation of the structure results in the additional nonlinear terms (square and cubic) in the dynamic equation. The above results are also in agreement with numerical simulation. Experimental and theoretical investigation demonstrate that pre-deformation and the amplitude of excitation significantly affect system FRF performance.
Zhao Huandi;Wang Jun;Chen Lifen.
EXPERIMENTAL STUDY OF FREQUENCY RESPONSES IN A BEAM STRUCTURE SUPPORTED WITH NONLINEAR STIFFNESS[J]. Journal of Vibration and Shock, 2015, 34(4): 82-89
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