i-manager Publications

Modal Analysis of Hyperboloidal Shell Structures

A. Kavya Reddy*, B. D. V. Chandra Mohan Rao**

* Department of Civil Engineering, VNR Vignana Jyothi Institute of Engineering and Technology, Hyderabad, Telangana, India.

** Professor, Department of Civil Engineering, VNR Vignana Jyothi Institute of Engineering and Technology, Hyderabad, Telangana, India.

Periodicity:March - May'2019
DOI : https://doi.org/10.26634/jce.9.2.16148

Abstract

Hyperboloidal shell structures have applications like cooling towers in thermal power plants. These types of structures have complex geometry and may lead to the failure because of its imperfections in geometry, when subjected to horizontal loads. Geometrical optimization of such structures leads to minimum stresses and deflections and finds out best possible load bearing behavior. This paper deals with the modal analysis of hyperboloidal shell structures of two different heights (143.5 m and 175.5 m). The hyperboloidal shells are modelled by varying height to top diameter ratio (1.5, 1.75, 2.0, 2.25, 2.5) and height to bottom diameter ratio (1.3, 1.35, 1.4, 1.45, 1.5). Free vibration analysis has been carried out for all the models described above to obtain the fundamental natural time periods / frequencies and mode shapes. This analysis has been carried out using ANSYS and finally, some useful conclusions are drawn.

Keywords

Hyperboloidal Shell Structures, Cooling Tower, Free Vibration Analysis, Time Period, Mode Shape, Height to Top Diameter Ratio, Height to Bottom Diameter Ratio

How to Cite this Article?

Reddy, A. K., & Rao, B. D. V. C. M. (2019). Modal Analysis of Hyperboloidal Shell Structures, i-manager's Journal on Civil Engineering, 9(2), 55-61. https://doi.org/10.26634/jce.9.2.16148

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Modal Analysis of Hyperboloidal Shell Structures

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