Affiliation:
1. Department of Civil Engineering, New Mexico State University, Las Cruces, NM 88003, USA
2. Department of Civil and Environmental Engineering, Cleveland State University, Cleveland, OH 44115, USA
Abstract
Ultra-high performance concrete (UHPC) is a novel cement-based material with exceptional mechanical and durability properties. Silica fume, the primary supplementary cementitious material (SCM) in UHPC, is expensive in North America, so it is often substituted with inexpensive class F fly ash. However, future availability of fly ash is uncertain as the energy industry moves toward renewable energy, which creates an urgent need to find cost-effective and environmentally friendly alternatives to fly ash. This study investigated replacing cement, fly ash, and silica fume in UHPC mixtures with ground granulated blast-furnace slag (GGBFS), metakaolin, and a natural pozzolan (pumicite). To identify acceptable UHPC mixtures (28-day compressive strength greater than 120 MPa), workability, compression, and flexural tests were conducted on all mixtures. Then, durability properties including shrinkage, frost resistance, and chloride ion permeability (rapid chloride permeability and surface resistivity tests) were evaluated for the acceptable UHPC mixtures. Results showed that 75, 100, and 40% of fly ash in the control mixture could be replaced with pumicite, metakaolin, and GGBFS, respectively, while still producing acceptable strengths. Flexural strengths were greater than 14.20 MPa for all mixtures. For durability, UHPC mixtures had shrinkage strains no greater than 406 μstrain, durability factors of at least 105, and “very low” susceptibility to chloride ion penetration, indicating that these SCMs are suitable candidates to completely replace fly ash and partially replace silica fume in non-proprietary UHPC.
Funder
Transportation Consortium of South-Central States
New Mexico State University
Subject
General Materials Science
Reference63 articles.
1. Durability of an Ultrahigh-Performance Concrete;Graybeal;J. Mater. Civ. Eng.,2007
2. (2017). Standards Practice for Fabricating on Testing Specimens of UHPC (Standard No. ASTM C1856/M-17).
3. (2019). Concrete Materials and Methods of Concrete Construction, Annex U-Ultra-High Performance Concrete (UHPC) (Standard No. CSA A23.1).
4. (2016). Béton Fibré Ultra-Performant (BFUP)-Matériaux, Dimensionnement et Exécution (Ultra-High Performance Fibre Reinforced Cement-Based Composites [UHPFRC]- Construction Material, Dimensioning and Application) (Standard No. SIA 2052).
5. Graybeal, B. (2014). Design and Construction of Field-Cast UHPC Connections, FHWA, U.S. Department of Transportation. Publication No. FHWA HRT-14-084.
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