DOI QR코드

DOI QR Code

Evaluation of vertical dynamic characteristics of cantilevered tall structures

  • Li, Q.S. (Department of Building and Construction, City University of Hong Kong) ;
  • Xu, J.Y. (Department of Civil Engineering, Wuhan University of Technology) ;
  • Li, G.Q. (Department of Civil Engineering, Wuhan University of Technology)
  • 발행 : 2001.04.25

초록

In this paper, cantilevered tall structures are treated as cantilever bars with varying cross-section for the analysis of their free longitudinal (or axial) vibrations. Using appropriate transformations, exact analytical solutions to determine the longitudinal natural frequencies and mode shapes for a one step non-uniform bar are derived by selecting suitable expressions, such as exponential functions, for the distributions of mass and axial stiffness. The frequency equation of a multi-step bar is established using the approach that combines the transfer matrix procedure or the recurrence formula and the closed-form solutions of one step bars, leading to a single frequency equation for any number of steps. The Ritz method is also applied to determine the natural frequencies and mode shapes in the vertical direction for cantilevered tall structures with variably distributed stiffness and mass. The formulae proposed in this paper are simple and convenient for engineering applications. Numerical example shows that the fundamental longitudinal natural frequency and mode shape of a 27-storey building determined by the proposed methods are in good agreement with the corresponding measured data. It is also shown that the selected expressions are suitable for describing the distributions of axial stiffness and mass of typical tall buildings.

키워드

참고문헌

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피인용 문헌

  1. Nonlinear Analysis of Single-Layer Reticulated Spherical Shells Under Static and Dynamic Loads vol.10, pp.5, 2004, https://doi.org/10.1177/1077546304040236
  2. Nonlinear elastoplastic dynamic analysis of single-layer reticulated shells subjected to earthquake excitation vol.81, pp.4, 2003, https://doi.org/10.1016/S0045-7949(02)00445-5