Document Type : Regular Paper
Ph.D. Candidate of Structural Engineering, University of Mohaghegh Ardabili, Ardabil, Iran
Ph.D., Civil Engineering Department, Mohaghegh Ardabili University, Ardabil, Iran.
Associate Professor of Civil Engineering, University of Mohaghegh Ardabili, Ardabil, Iran
The purpose of this study is to obtain one of the important dynamical properties, namely natural frequency (ω) for a number of tall buildings with tube and tapered tube systems. Furthermore, it presents an approximate method to analyze the free vibration of tall buildings by tube, tube-in-tube, bundled tube, and tapered tube structures. The method we have proposed would enable us to compute the natural frequency of tubular vertical and tapered tall buildings by the help of computer programming. The models were analyzed by finite element and analytical methods. The results indicate that the investigated analytical method correctly calculates the natural frequency and is in decent accord with the finite element results and has better compatibility with tapered structures without angle with higher altitude. The resulting computational error is very low. Also, this analytical method has the least error for tube systems and the highest error is for tube-in-tube systems.