Title: Buckling of Thin Concrete Domes

Author(s): Mehdi S. Zarghamee and Frank J. Heger

Publication: Journal Proceedings

Volume: 80

Issue: 6

Appears on pages(s): 487-500

Keywords: buckling; compressive strength; computer programs; creep properties; domes (structural forms); mathematical models; prestressed concrete;reinforced concrete; shells (structural forms); spherical shells; structural design; tanks (containers).

DOI: 10.14359/10870

Date: 11/1/1983

Abstract:
A design procedure for determining the buckling strength of concrete domes with prestressed concrete edge rings is presented. This procedure was developed using a conceptual model for predicting the buckling strength of concrete domes based on the available literature on stability of spherical shells and creep of concrete. The model is based on the assumption that the dome contains geometric imperfections in the form of spherical caps with different radii of curvature. The buckling strength of the dome is governed by the buckling strength of the least resistant cap. To predict the buckling strength of a shallow concrete cap including the effects of geometric nonlinearity, creep, and material nonlinearity, a computer analysis of the buckling strength of spherical caps having several shallowness parameters in the critical range was performed using the BOSORS computer program. The effect of cracking on the buckling strength was approximated by examining the stress states prior to buckling and judiciously selecting the time of failure. The paper also contains the results of a survey conducted on 245 thin concrete domes built over large prestressed concrete tanks during the past two to three decades. These tend to substantiate the adequacy of the proposed design procedure for such domes. Also, a survey of the actual geometry of a dome known to exhibit very severe imperfections and an evaluation of published creep buckling test results were conducted for further evaluation and validation of the proposed design procedure.