TY - JOUR A1 - Falchi, L. A1 - Zendri, E. A1 - Müller, U. A1 - Fontana, Patrick T1 - The influence of water-repellent admixtures on the behaviour and the effectiveness of Portland limestone cement mortars N2 - Water-repellent mortars were prepared using different hydrophobic compounds as admixtures. Calcium and zinc stearates, silane/siloxane products (as liquid solution and powder) were mixed into limestone cement mortars for obtaining in-bulk water-repellent mortars suitable for building protection and resistant to the degrading action of water. The influences of the admixtures on the hydration and structure of the designed mortars were investigated by SEM, TG–DSC, FT-IR, XRD, and isothermal calorimetry. The effectiveness of these agents against water action was evaluated by using techniques and methods such as mercury intrusion porosimetry, water absorption tests and contact angle measurements. Siloxane products conveyed good water-repellent effectiveness, without strongly influencing the setting and hydration of the binder, while the zinc stearates slowed down the hydration reactions. KW - Water repellent admixtures KW - Portland limestone cement mortars KW - Hydration products KW - Pore size distribution KW - Siloxanes KW - Stearates PY - 2015 DO - https://doi.org/10.1016/j.cemconcomp.2015.02.004 SN - 0958-9465 SN - 1873-393X VL - 59 SP - 107 EP - 118 PB - Elsevier Ltd. CY - Barking, Essex AN - OPUS4-33169 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Falchi, L. A1 - Fontana, Patrick A1 - Izzo, F.C. A1 - Zendri, E. A1 - Mueller, U. T1 - Influence and effectiveness of water-repellent admixtures on pozzolana-lime mortars for restoration application N2 - Pozzolana–lime mortars modified with water-repellent admixtures were designed and studied to obtain mortars for restoration application. Powdered silane and calcium stearates were mixed with pozzolana, lime and sand and the chemical–physical properties of the resulting mortars were evaluated by X-ray diffraction, electron microscopy (SEM-EDX), thermogravimetric analysis and FT-IR spectroscopy. The mechanical behavior, the pore structure and the hygric behavior were measured. The resistance of water-repellent mortars to the salt crystallization was evaluated. Both calcium stearates and powdered silane allowed good water-repellent protection even if the water-repellent agents and their dosage modified some physical properties and the hydration kinetic. KW - Water-repellent admixtures KW - Pozzolana-lime mortars KW - Water absorption KW - Hydration KW - Stearates KW - Silane KW - Restoration PY - 2013 DO - https://doi.org/10.1016/j.conbuildmat.2013.08.030 SN - 0950-0618 VL - 49 SP - 272 EP - 280 PB - Elsevier Science CY - Amsterdam AN - OPUS4-29940 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -