Nonlinear vibrations of a coupled beam-arch bridge system

Publication date: Available online 4 October 2019Source: Journal of Sound and VibrationAuthor(s): Vladimir Stojanović, Marko D. Petković, Dunja MilićAbstractA characteristic engineering example of the model presented in this paper, which consists of a viscoelastically and nonlinearly coupled beam-arch system, can be found in the physical model of a bridge. Here, the beam analogue of von Kármán's nonlinear strain-displacement relationships is used. After that the p-version of the finite element method is employed for the coupled system's geometrically nonlinear responses. In order to investigate the features of the arch's curvatures, a nonlinear analysis is performed in the time domain by the Newmark method and in the frequency domain by harmonic balance and continuation methods. The main contribution of the work is the discovery that the upper excited beam (in a double-beam model) goes back to the amplitude-symmetric vibration regime (as in the case of an excited single beam model) only if the lower beam is curved for the same excited scenario. That phenomenon comes from the nonlinear couplings in the beam-arch system and cannot be detected in the linear regime, while its existence is not evident without the analysis presented in this paper. Therefore, the non-symmetric higher amplitude deviations in the steady state regime of vibrations of the upper beam are transferred to the lower beam, only if the latter is curved. The paper shows that this nonlinear phenomenon is a ...

Source: Journal of Sound and Vibration - October 4, 2019 Category: Physics Source Type: research