Title: Characterizing Sticky Concrete from Rheological Perspective

Author(s): Elizabeth G. Burns, Danila F. Ferraz, and Nathan A. Tregger

Publication: Materials Journal

Volume: 118

Issue: 6

Appears on pages(s): 421-429

Keywords: high-range water reducer (HRWR); polycarboxylate; rheology; small-amplitude oscillatory rheometry (SAOS); stickiness

DOI: 10.14359/51734154

Date: 11/1/2021

Abstract:
Increasing urbanization is driving the construction of tall buildings in congested areas. Tall buildings call for concrete with high compressive strength and modulus of elasticity, resulting in a low water-cementitious materials ratio (w/cm) and high cementitious content mixtures. At these lower w/cm, such mixtures are typically “sticky” and difficult to pump or finish. However, high-rise construction requires pumping such “sticky” concrete, potentially leading to high pumping pressures and clogged pumps. The word “sticky” does not have a clear technical definition, nor is it currently associated with specific rheological mechanisms. This article explores the quantification of “stickiness” through small amplitude oscillatory rheometry. This work is a step toward connecting the human perception of stickiness and fundamental rheological properties.