Work

Utilization of calcareous fly ash with Lopburi calcined clay as high Portland cement replacement supplementary cementitious materials

Year: 2025

Type: article

Abstract: Calcined clay and calcareous fly ash were used as supplementary cementitious materials to replace Portland cement at 50% by weight to produce a more environmentally friendly binder with a lower carbon footprint. Up to 30% of calcined clay was used while calcareous fly ash was used at 20-50%. Compressive strength and phase characterizations were investigated for these samples at 7 and 28 days to provide understandings of the phases formed during hydration. It is found that at both ages, the use of calcined clay in addition to fly ash resulted in an increase in the hydration phases as early as 7 days when compared to the reference fly ash mix and is more pronounced at 28 days. This relates with the increase in compressive strength of the mixes where the compressive strength of fly ash mixes with 15-20% calcined clay are found to be 40 to 41 MPa compared to 27 MPa of reference fly ash mix (50% fly ash). Using both thermogravimetric analysis (TG) and X-ray diffraction (XRD), a number of phases were detected such as calcium silicate hydrate (C-S-H), calcium aluminosilicate hydrate (C 2 ASH 8 ) and monocarboaluminate hydrate. A noticeable reduction in calcium hydroxide (CH) was also clear when increasing calcined clay.

Source: Case Studies in Construction Materials

DOI: 10.1016/j.cscm.2025.e05228

Authors: Arnon Chaipanich, Wisawin Promwijit, Ananya Nararueang, Supakporn Aodkeng, Kornnika Wianglor

Institution: Chiang Mai University

Language: English

Topic: Concrete and Cement Materials Research

Subfield: Civil and Structural Engineering

Field: Engineering

Domain: Physical Sciences

SDGs: Responsible consumption and production, Climate action

Open Access status: gold

Estimated APC paid: $2,660