Finite Element Analyses of Cracked Cooling Tower Shell

Abstract

The limit of serviceability and the residual safety against structural collapse of a concrete cooling tower, which was built 25 years ago, is evaluated numerically by the finite element method. The present condition of the shell includes a relatively large number of long meridional cracks. The process of damage is simulated by means of applying different thermal load histories. Each of them is followed by the incremental application of the wind load. For purposes of comparison, results from ultimate (wind) load analysis of the originally uncracked shell are presented. From the analyses it is concluded that the degree of corrosion, for which several assumptions are made, controls the safety of the cooling tower. With respect to the sensitivity of the structural response concerning the value of the tensile strength, the effectiveness of a repair by attaching stiffening rings to the shell and the influence of the location of a single ring on the structural response also are investigated.