Title: Acid Resistance of Sewer Pipe Concrete Mixtures

Author(s): M. G. Alexander and C. W. Fourie

Publication: Symposium Paper

Volume: 192

Issue:

Appears on pages(s): 705-720

Keywords: acid resistance; sewer pipes silica fume

DOI: 10.14359/5780

Date: 4/1/2000

Abstract:
The acid resistance of six different sets of concrete materials was measured using hydrochloric acid in a test method developed at the University of Cape Town. The concrete mixtures included a standard mix used for the preparation of sewer pipes by the roller suspension method, and five modifications of the standard mix. Four of the test mixtures were modified by partial replacement of normal portland cement with a mineral admixture, namely slag, fly ash, condensed silica fume or meta-kaolin. In the fifth test mixture, normal portland cement was replaced with a calcium aluminate cement. Silica fume concrete showed better acid resistance compared to the standard concrete. In general, at 28 days the physical properties of concrete with fine mineral admixtures (condensed silica fume, meta-kaolin) were superior to the other concretes. However, the acid resistance of the meta-kaolin concrete was not improved despite its superior quality. Improvement in the acid resistance of the concrete with condensed silica fume indicates that the concrete is improved both chemically and physically by the addition of silica fume.