Analytically measure the vibratory characteristics of the cable-stayed bridge during dual-cantilever erection

Abstract

To analytically measure the vibratory characteristics of the cable-stayed bridge with beam-tower constraint during the dual-cantilever erection, the isolating/assembling technique is used to derive the global equation. Eigen-equation governing the frequencies/modes is obtained by applying the coefficients vectors transferring between adjacent cable-beams and the boundary/matching conditions. An illustrative example of the dual-cantilever erection system is given to verify the effectiveness of the analytical method by comparing with the finite element method. The influences of the vertical/rotational beam-tower constraint stiffness and the beam/cable relative stiffness on the frequencies/modes are studied; the sensitive interval and unstable/veering regions in frequency spectrum are ascertained. The twin frequencies are analytically measured and it is found that the symmetry plays a fundamental role in its existence and distribution range. The measuring method supplies reference for similar cable-supported structures; the results provide suggestions to avoid unstable/veering zone depending on the designed parameters combination in cable-stayed bridge.

Two elastic supporting models to simulate the submerged floating tunnel and their equivalence on the free/forced vibrations

“…It should be particularly pointed that the order of Θ 0 in equation (19) for the ESB model is 4 × 4 for any number of intermediate k si . The transferring technique used here is inconsistent to that of other chained structures (Yi et al, 2019, 2021) where the influence of the number/non-uniformity of the elastic supports are not considered. The proposed ESB model is also different to the continuous beams (Johansson et al, 2013; Ariaei et al, 2013) whose order of the eigen-equation is rapidly increasing with the growth of the intermediate supports’ number.…”