The pore structure in lime plaster as a key to understanding moisture transportation properties and frost damages

Paper in proceeding, 2004

The pore structure is of great importance for a materials ability to hold and transport gas and moisture. In lime plaster, it affects hardening, carbonation as well as durability against frost damage. In the present paper, eleven mixtures of lime mortar were studied with respect to frost damages. The binders used were lime slaked in four different ways, hydraulic lime and cement. Several analyses were made to characterize the transport properties and the pore structure of the materials; density, porosity, sorption curves, capillary water suction and thin sections. This study shows that there is a correlation between pore structure and important material properties. By studying these parameters, it is possible to get a good picture of the materials ability to resist frost damages. The study also gives an indication of what materials in the mortar such as binders, aggregates and water, give a good pore structure.