RT Conference Proceedings
T1 Advanced 3D nanoimaging of cement paste hydration using synchrotron Xray ptychographic tomography
A1 Shirani, Shiva
A1 Cuesta, Ana
A1 Santacruz-Cruz, María Isabel
A1 Gómez-de-la-Torre, María de los  Ángeles
A1 Diaz, Ana
A1 Trtik, Pavel
A1 Holler, Mirko
A1 García-Aranda, Miguel Ángel
K1 Cemento Portland
AB Hydration of Portland cements (PC) is a complex phenomenon caused by the presence of multiplecomponents with multi-length scale variability. To investigate this complicated process, state-of-theart3D nanoimaging techniques with excellent spatial resolution and the ability to scan large fields ofview are required. In this work, synchrotron X-ray near-field ptychographic tomography is used tostudy four cement pastes within 0.2 mm thick capillaries.Synchrotron ptychotomography produces electron density and absorption coefficient tomograms thatfacilitate the characterisation of amorphous materials. By achieving a spatial resolution of around 220nm with good contrast, nanofeatures such as the density and spatial distribution of amorphousconstituents can be identified.Key findings include the revelation that a seeded C-S-H gel has a lower density than a CaCl2 acceleratedPC paste. In addition, the density of the C-A-S-H gel in a PC blend containing metakaolin and limestonedecreases when limestone is present. These density variations are critical in estimating the space fillingin the paste.C-S-H nucleation seeding results in a reduced inner/outer C-S-H gel ratio, with different average sizesof high-density inner C-S-H gel found under different hydration conditions. Various additives, includingnucleation seeding admixtures and CaCl2, alter the water/cement ratio and the overall density of theC-S-H gel. The addition of alkanolamine admixture increases C4AF hydration, resulting in thedevelopment of amorphous Al-rich iron-silicate hydrogarnet, which affects C4AF dissolution. Theaddition of limestone to the PC-MK blend changes the electron density of the C-A-S-H gel and increasesthe production of amorphous monocarboaluminate-like components, which influences porosityrefinement.
YR 2024
FD 2024-06-25
LK https://hdl.handle.net/10630/33876
UL https://hdl.handle.net/10630/33876
LA eng
NO Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech.
DS RIUMA. Repositorio Institucional de la Universidad de Málaga
RD 27 feb 2026