Читать книгу Monument Future - Siegfried Siegesmund - Страница 74

In order to improve the ecological footprint of the restauration mortars while keeping their efficiency, we have tested several combinations of natural hydraulic lime and air lime with natural aggregates and additives. Repair mortars should be compatible with the support (stones, bricks) and protect original materials from environmental agents; aesthetical and historic aspects must not be neglected. We started by “simple” mixtures of lime and natural siliceous sand or crushed calcareous limestone. Aggregates granulometry was 0/2 mm in all the cases. More “complex” mortars were also prepared by incorporating the additives pinecone resin, semimilled cones of pine, milled glass waste, chamotte (brick production residue).

Different physical properties have been measured in all mortars: porosity, density, capillarity absorption, mechanical strength (flexural and compression), P and S waves velocities from which dynamic Young’s modulus and Poisson’s ratio were inferred. Durability of mortars has been estimated by salt crystallization and frost/thaw cycles.

Keywords: Restoration mortars, sustainable Cultural Heritage conservation, Building materials, Durability