Title: Lift Stations-A Testing Ground for Concrete Durability

Author(s): Shondeep L. Sarkar

Publication: Symposium Paper

Volume: 170

Issue:

Appears on pages(s): 1357-1378

Keywords: Carbonation; concretes; durabilty; ettringite; gypsum; sulfuic acid; sulfate attack.

DOI: 10.14359/6882

Date: 7/1/1997

Abstract:
A network of lift stations forms an integral part of a city’s wastewater disposal system. These underground concrete pits through which the sewage is pumped, are known to represent an environment highly conducive for chemical attack of concrete. Apart from the acidic state created by the sewage, gases emanated due to microbial reactions can cause the concrete to deteriorate rapidly. Fifteen lift stations were investigated to determine the deterioration depth profile of the concretes. Cores from strategic locations inside each lift station were tested and analyzed using different techniques, including petrography and scanning electron microscopy. Based on these results, a cost-effective yet practical means of evaluating the present state of the concrete, and the precise depth to which the concrete must be removed for effective rehabilitation has been developed. These results are presented in this paper.