Title: Lignosulphonate as Plasticizing Admixture on Cements of Different Chemical Composition

Author(s): B. G. Petersen, K. Reknes, and K. Olavesen

Publication: Symposium Paper

Volume: 222

Issue:

Appears on pages(s): 93-108

Keywords: adsorption; concrete matrix; lignosulphonate; rheology; superplasticizer

DOI: 10.14359/13307

Date: 5/1/2004

Abstract:
Lignosulphonate is a widely used plasticizing admixture in concrete. It is well documented that different qualities of this material give different performance in concrete. Depending on what kind of concrete that is needed, workability can be controlled by adding different amounts or qualities of the lignosulphonate. This investigation compares the adsorption of lignosulphonate on three different portland cements, to the rheological properties of cement pastes made from the same cements. The adsorption isotherms were calculated from depletion experiments. A rheometer with bob-cup geometry was used to measure the rheological properties of the cement pastes. The plasticizing effect of lignosulphonates in cement paste slurries was confirmed. Recent advances have given a novel lignosulphonate with superplasticizer performance. This investigation demonstrates these improved properties achieved by this novel lignosulphonate by determining the differences in adsorption of the different lignosulphonates, on cements with different chemical characteristics.