Temporal flowability evolution of slag-based self-compacting concrete with recycled concrete aggregate

JOURNAL OF CLEANER PRODUCTION

卷:299

Article

Revilla-Cuesta, Victor¹  Skaf, Marta²  Santamaria, Amaia³  Hernandez-Bagaces, Jorge J.²  Ortega-Lopez, Vanesa¹ 

[1] Univ Burgos, Dept Civil Engn, EPS Calle Villadiego S-N, Burgos 09001, Spain

[2] Univ Burgos, Dept Construct, EPS Calle Villadiego S-N, Burgos 09001, Spain

[3] Univ Basque Country, Dept Mech Engn, UPV EHU, Escuela Ingn Bilbao, 1 Bloque B UPV EHU,Plaza Ingn Torres Quevedo 1, Bilbao 48013, Spain

关键词: Self-compacting concrete;    Recycled concrete aggregate;    Ground granulated blast furnace slag flowability;    viscosity and passing ability evolution;    Sieve segregation;    Air content;   

DOI  :  10.1016/j.jclepro.2021.126890

来源: Elsevier

【 摘 要 】

The addition of by-products, such as recycled concrete aggregate and ground granulated blast furnace slag, modify the in-fresh flowability of ordinary self-compacting concrete both initially and over time. A detailed study is presented in this paper of 18 mixtures (SF3 slump-flow class) containing 100% coarse recycled concrete aggregate, two types of cement (CEM I or CEM III/A, the latter with 45% ground granulated blast furnace slag), different contents of fine recycled concrete aggregate (0, 50, or 100%), and three different aggregate powders (ultra-fine limestone powder <0.063 mm, limestone fines 0/0.5 mm, and recycled concrete aggregate 0/0.5 mm). The temporal evolution of slump flow, viscosity, and passing ability, and the values of segregation resistance, air content, fresh and hardened density, and compressive strength were evaluated in all the mixtures. The addition of fine recycled concrete aggregate and CEM III/ A improved initial slump flow and passing ability by 6%, due to their higher proportion of fines. Nevertheless, the temporal loss of flowability within 60 min was 5.8% lower when adding natural aggregate and CEM I. Viscosity and air content increased 26% on average following additions of fine recycled concrete aggregate, unlike with additions of ground granulated blast furnace slag. Flowability and strength increased with the addition of limestone fines 0/0.5 mm. According to multi-criteria analyses, the mixtures with CEM III/A, 50% fine recycled concrete aggregate, and limestone fines 0/0.5 mm showed an optimal balance between their flowability (SF2 slump-flow class 60 min after the mixing process), compressive strengths (around 60 MPa), and carbon footprints. (C) 2021 Elsevier Ltd. All rights reserved.

【 授权许可】

Free