Title: Impact of Lignin-Based AE Water- Reducing Agent, and BNS- and PCE-Based Superplasticizers on the Properties of Hardened Concrete

Author(s): M. Ohno, T. Sugiyama, T. Sugamata, and A. Ohta

Publication: Symposium Paper

Volume: 262

Issue:

Appears on pages(s): 371-380

Keywords: B-naphthalenesulfonate-based (BNS); durability; ligninbased; polycarboxylate superplasticizer.

DOI: 10.14359/51663246

Date: 10/1/2009

Abstract:
Lignosulfonate-based air-entraining (AE) water-reducing agents have been used in various concrete structures for over 50 years. Polycarboxylate-based superplasticizers, which are the main superplasticizers in use today, have been on the market for 20 years and have recently been applied to various kinds of concrete structures. Therefore, it is important to know the difference that these three dispersants (lignosulfonate-based (LG), B-naphthalenesulfonate-based (BNS), and polycarboxylate-based (PC)) have on concrete durability. The authors, using superplasticizers containing each dispersant, studied the properties of concrete at a w/c of 0.50 up to the age of 20 years. This paper discusses the experimental results up to the age of 3 years following standard curing and artificial sea water curing, and under normal external exposure and exposure in a splash zone. As a result, no major difference has been observed in the effect on properties of the hardened concrete between PC and BNS, dispersants in superplasticizers. In addition, the authors consider that concrete incorporating PC-based superplasticizer or BNS-based superplasticizer has equal durability to that of concrete incorporating an AE waterreducing agent, most of which is in service over the long term.