Effect of Admixture Dosage and Specimens Age on Mechanical Fracture Parameters of Lime Mortars Enhanced by Burnt Clays

Abstract

In the restoration of historic buildings with priorities of historic preservation there exists an effort to modify the mortars by admixtures which are in compliance with historical materials and techniques. Therefore the specimens were made from lime mortar modified by brick powder or metakaolin. The reference mixture used only hydrated lime while the other mixtures were enhanced by brick powder or metakaolin in the amounts of 25, 50 and 100 % of the weight of hydrated lime. This paper presents the results of three-point bending fracture tests obtained by using double-K fracture model. The specimen’s age was 90 and 150 days.