Development of reactive MgO-based Engineered Cementitious Composite (ECC) through accelerated carbonation curing

Journal Article · Mon Oct 08 00:00:00 EDT 2018 · Construction and Building Materials

DOI:https://doi.org/10.1016/j.conbuildmat.2018.09.196· OSTI ID:1990028

Wu, Hao-Liang ^[1]; Zhang, Duo  ^[2]; Ellis, Brian R. ^[2]; Li, Victor C. ^[2]

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1. Southeast University, Nanjing (China)
2. University of Michigan, Ann Arbor, MI (United States)

The use of reactive magnesium oxide (MgO) is widely recognized in carbonated concrete formulations associated with permanent sequestration of CO₂. Engineered Cementitious Composite (ECC) is an advanced fiber reinforced cement-based composite with high tensile ductility and intrinsically tight crack width. In this paper, we investigate an alternative binary binding system for ECC: reactive MgO and fly ash cured with an accelerated carbonation process. Compressive strength, density, carbonation depth, tensile performance and crack pattern of the carbonated reactive MgO-based ECC were investigated at various curing ages. In addition, the CO₂ uptake and materials sustainability, in terms of energy consumption, net CO₂ emission and cost of the newly developed ECC were assessed. The objective of this research is to further advance the application of reactive MgO and utilization of CO₂ in the construction industry through novel ECC material. It was observed that carbonation curing densifies the binding system, thus leading to an increase in both compressive and first cracking tensile strengths of ECC. The tensile strain capacity of the carbonated reactive MgO-based ECC achieved up to 6% with an average crack width below 60 μm after 1-day carbonation. Compared to conventional ECC (M45) and concrete, the 1-day carbonated reactive MgO-based ECC could reduce the net CO₂ emission by 65% and 45%, respectively. It is concluded that environmental and technical benefits could be simultaneously achieved for the 1-day carbonated reactive MgO-based ECC incorporated with 50% fly ash. Furthermore, the findings of this research shed light on further applications of reactive MgO cement in the precast industry.

• Research Organization: Univ. of Michigan, Ann Arbor, MI (United States)
• Sponsoring Organization: USDOE Office of Fossil Energy (FE), Clean Coal and Carbon Management; Scientific Research Foundation of Graduate School of Southeast University
• Grant/Contract Number: FE0030684; YBJJ1735
• OSTI ID: 1990028
• Journal Information: Construction and Building Materials, Vol. 191; ISSN 0950-0618
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
Engineered Cementitious Composite (ECC)
Reactive MgO
Tensile ductility
Carbonation curing
CO2 utilization