Work

In-situ characterisation of early hydration of low-carbon cements containing thermally and mechanically activated kaolin

Year: 2024

Type: article

Abstract: This study investigates the early hydration mechanism of limestone calcined clay cement (LC 3 ) system containing mechanically activated clay (MC) replacing thermally activated clay (calcined clay, CC). The phase assemblage including portlandite , ettringite , and carboaluminates was monitored using in-situ confocal Raman microscopy (CRM) and X-ray diffraction (XRD), and the hydration kinetics were studied through isothermal calorimetry (IC). Results revealed accelerated hydration in LC 3 -MC compared to LC 3 -CC, attributed to enhanced filler effect, increased reactivity, and the earlier formation of reaction products such as C-S-H gel. The different characterisation techniques demonstrated the earlier formation of portlandite and ettringite in LC 3 -MC, with significant differences in water distribution and composition patterns. Mechanical activation also led to more rapid and extensive formation of carboaluminates, improving early-age compressive strength . These findings highlight the potential of mechanically activated clay in LC 3 systems to enhance the sustainability and performance of cementitious materials by optimising clinker replacement strategies.

Source: Construction and Building Materials

DOI: 10.1016/j.conbuildmat.2024.139469

Authors: Jofre Mañosa, Manuel Torres-Carrasco, Javier C. Córdoba, Alex Maldonado-Alameda, Josep Maria Chimenos

Institutions: Universitat de Barcelona, Universidad Carlos III de Madrid

Language: English

Topic: Concrete and Cement Materials Research

Subfield: Civil and Structural Engineering

Field: Engineering

Domain: Physical Sciences

SDGs: Responsible consumption and production, Industry, innovation and infrastructure

Open Access status: hybrid

Estimated APC paid: $4,080