Title: Self-Consolidating Concretes Made with Cold-Bonded Fly Ash Lightweight Aggregates

Author(s): Hatice Oznur Oz, Mehmet Gesoglu, Erhan Guneyisi, and Nadhim Hamah Sor

Publication: Materials Journal

Volume: 114

Issue: 3

Appears on pages(s): 385-395

Keywords: fracture; hardened properties; lightweight aggregate; pelletization method; self-consolidating lightweight-aggregate concrete

DOI: 10.14359/51689606

Date: 5/1/2017

Abstract:
An experimental program was conducted to investigate the mechanical, fracture, and physical properties of self-consolidating lightweight concretes (SCLCs) made with cold-bonded fly ash (FA) aggregates. A total of 17 SCLCs were designed with a water-binder ratio (w/b) of 0.32, in which the natural aggregates were partially replaced with cold-bonded lightweight fine aggregate (LWFA) and lightweight coarse aggregate (LWCA) at different volume fractions of 10, 20, 30, 40, and 50%. Hardened properties of the SCLCs were tested for bond strength, fracture energy, characteristic length, drying shrinkage, weight loss, and restrained shrinkage cracking. It was observed that the SCLCs had relatively lower compressive and splitting tensile strengths with increasing LWFA and/or LWCA in the mixtures. Bond strength of the SCLCs decreased gradually with the replacement level of LWA because the bond strength directly depended on the quality of the cement paste and aggregate. Although SCLCs had significantly poorer restrained shrinkage cracking performance than the control concrete, the time to cracking greatly lengthened as the replacement level of LWA increased.