RT Journal Article
T1 Local structure and Ca/Si ratio in C-S-H gels from hydration of blends of tricalcium silicate and silica fume
A1 Dapiaggi, Monica
A1 Santacruz-Cruz, María Isabel
A1 Cuesta-García, Ana María
A1 Gómez-de-la-Torre, María de los  Ángeles
A1 Zea-Garcia, Jesus D.
A1 García-Aranda, Miguel Ángel
K1 Cemento Portland
K1 Cemento - Aditivos
AB At the microscale, C-S-H gels from alite, or neat Portland cements, has a Ca/Si ratio close to 1.80. At the nanoscale, C-S-H is described by a defective tobermorite structure which allows a maximum Ca/Si ratio close to 1.40. There is no agreement in the location of the extra 0.40 moles of Ca(OH)2 at the nanoscale. Atomistic modelling studies reported Ca(OH)2 species within the tobermorite interlayer space. Other works point toward a fine intermixing of defective tobermorite and nanoportlandite. Here, we have prepared a series of alite blended with silica fume and studied the pastes by several techniques including synchrotron pair distribution function (PDF). In the employed conditions, the C-S-H gel formed by the pozzolanic reaction has nearly the same local structure than the primary C-S-H gel. Furthermore, differential PDF points toward Ca(OH)2 excess having a local structure compatible with few-layer thick nanoparticles stretched along the c-axis.
PB Elsevier
YR 2021
FD 2021-03
LK https://hdl.handle.net/10630/21061
UL https://hdl.handle.net/10630/21061
LA eng
NO Cement and Concrete Research 143 (2021) 106405
NO This work has been supported by two research grants, BIA2017-82391-R and PID2019-104378RJ-I00, which are co-funded by FEDER. We also thank CELLS-ALBA (Barcelona, Spain) for providing synchrotron beam time at BL04-MSPD and Alicia Manjón and Oriol Vallcorba for their assistance during the experiment. We thank the contributions from two anonymous reviewers which have improved the quality and clarity of this work.
DS RIUMA. Repositorio Institucional de la Universidad de Málaga
RD 20 ene 2026