Search results for " ciment"
showing 3 items of 3 documents
Magnesium silicate hydrate (M-S-H) characterization : temperature, calcium, aluminium and alkali
2017
The various options to store radioactive wastes in deep geological strata considered in France or Switzerland include the use of large volumes of cementitious materials for infrastructure in contact with argillaceous rocks. So-called low-pH binders were developed to minimize disruption to the surrounding rock by the alkaline plume. Studies conducted on the interaction zone between concrete and clay systematically highlighted the formation of magnesium silicate phases including magnesium silicate hydrate (M-S-H) at the interfaces, which can presently be modeled only partially due to incomplete thermodynamic data. The purpose of this study was to characterize these phases in temperature, alum…
Finte Pietre. Architettura dell'apparire e conservazione dei valori culturali
2012
Il volume presenta gli esiti di una ricerca incentrata sulla conoscenza delle finiture architettoniche di pietra artificiale, con particolare attenzione agli intonaci brevettati nel 1901 dai fratelli Li Vigni. Le attività di studio sono condotte attraverso la ricognizione dei documenti conservati presso l’Archivio Centrale dello Stato a Roma, e compiono una rigorosa selezione e analisi dei brevetti con l’obiettivo di tracciare il percorso evolutivo dei metodi d’intonacatura ed evidenziare i legami che s’instaurano tra le ricerche in corso nei diversi paesi. Nel XIX secolo i ricercatori di molte nazionalità avviano una selezione critica delle ricette tramandate dal passato e perfezionano pro…
Study of the action of phosphate ions contained in the mixing water of the hydration of a Portland cement.
2005
Cementation is considered as the most attractive solution for the conditioning of low and intermediate radioactive wastes. The species contained in these wastes can strongly influence the reactivity of the cement pastes, it is in particular the case of the ortho-phosphate ions which are found in the evaporation concentrates. The aim of our work was to determine the influence of these ions on the hydration and the rheological properties of the cement pastes at early age as well as the mechanical and physical properties on the hardened material.