Nano-Tio2 in hydraulic lime-metakaolin mortars for restoration projects: physicochemical and mechanical assessmentNano-Tio2 in hydraulic lime-metakaolin mortars for restoration projects: physicochemical and mechanical assessment Peer-Reviewed Journal Publication Δημοσίευση σε Περιοδικό με Κριτές 2020-04-062019enIn recent years, lime mortars mixed with artificial or natural pozzolans are commonly used in restoration applications. The aim of this work is the assessment of carbonation, pozzolanic reaction, setting time, and mechanical properties of metakaolin-lime mortars mixed with crystalline nano-titania (nT) as additive. The studied mortars consist of hydrated lime and metakaolin in 60/40 ratio (wt%) and fine aggregates of either carbonate or silicate sand. The concentration of the nano-titania is equal to 6 (wt%) of the binder. For comparison purposes, three types of mortars and pastes are designed: Without the addition of nano-titania, with nT activated or not under UV irradiation. The evaluation of the carbonation and pozzolanic reaction over a 1.5-year curing period is carried out through thermal analysis (DTA/TG), infrared spectroscopy (FTIR) and X-ray diffraction analysis (XRD). The uniaxial compression and the three-point bending tests at 28 days, 3 months, and 6 months were carried out to evaluate mechanical properties. The addition of activated nano-titania, due to an increased photocatalytic activity, accelerated the setting of the mortars, improving at the same time the mechanical properties. The plastic behavior of the lime-metakaolin mortars with activated nT was attributed to the evolution of carbonation and pozzolanic reaction.http://creativecommons.org/licenses/by/4.0/Buildings911Kapetanaki_et_al_Buildings_9(11)_2019.pdfChania [Greece]Library of TUC2020-04-03application/pdf2.2 MBfree Kapetanaki Kali Καπετανακη Καλη Kapridaki Chrysi Καπριδακη Χρυση Maravelaki Pagona Μαραβελακη Παγωνα MDPI Carbonation Lime-metakaolin mortars Nano-TiO2 Pozzolanic reaction Setting time