RT Journal Article
T1 Supplementary cementitious material based on calcined montmorillonite standards
A1 Vallina, Diego
A1 Rodríguez-Ruiz, María Dolores
A1 Santacruz-Cruz, María Isabel
A1 Cuesta, Ana
A1 García-Aranda, Miguel Ángel
A1 Gómez-de-la-Torre, María de los  Ángeles
K1 Cemento
K1 Arcillas
AB The most effective approach to mitigating the environmental impact of cement production is through the uti-lisation of pozzolanic materials to prepare blended cement. Calcined kaolinitic clays are one of the mostpromising materials to be used as supplementary cementitious materials (SCM) due to their final performances.However, there are locations where kaolinitic rocks are not available. This work presents the study of twodioctahedral smectite standards from the Clay Minerals Society (CMS), SWy-3 and SAu-1, to be used as refer-ences. After thermal activation optimisation, their pozzolanic performances are compared with those of low-grade kaolinitic clay. On the one hand, raw SWy-3 has an amorphous content of ~80 wt%, considered mont-morillonite, with quartz and feldspars. The optimum calcination temperature was 800ºC, at which the smectite isfully dehydroxylated (as determined by thermal analysis) but not completely amorphized (as shown by powderdiffraction). After calcination (800ºC), with a median particle size by volume (Dv,50) of ~11 μm, ~480 J/g werereleased at 7 days in the R3 test. On the other hand, SAu-1 has a higher amount of amorphous content, ~96 wt%,which includes interstratified illite/smectite. The optimum calcination temperature was found to be 750ºC. Thissample (Dv,50 ~10 μm) gave 452 J/g at 7 days in the R3 test. The optimised active smectites gave a pozzolanicactivity comparable to clay with 30–35 % kaolinite, as determined, for the first time, by the R3 test. This work hasestablished descriptors for the activation of natural smectites/bentonites and reference values for the resultingsmectite-based SCMs.
PB Elsevier
YR 2024
FD 2024-05-03
LK https://hdl.handle.net/10630/31037
UL https://hdl.handle.net/10630/31037
LA eng
NO Diego Vallina, María Dolores Rodríguez-Ruiz, Isabel Santacruz, Ana Cuesta, Miguel A.G. Aranda, Angeles G. De la Torre, Supplementary cementitious material based on calcined montmorillonite standards, Construction and Building Materials, Volume 426, 2024, 136193, ISSN 0950-0618, https://doi.org/10.1016/j.conbuildmat.2024.136193.
NO Funding for open access charge: Universidad de Málaga / CBUA
DS RIUMA. Repositorio Institucional de la Universidad de Málaga
RD 22 ene 2026