Capillary absorption into CEBs and 2-layer composite building materials comprising of natural stone and CEBs

Department of Civil and Environmental Engineering, University of Cyprus, Nicosia, Cyprus

^* Corresponding author: panagiotou.rafail@ucy.ac.cy

Abstract

Earth-based building materials have been used since antiquity for the construction of various structures. The main drawback of these materials is their vulnerability to direct contact with liquid water, such as rising damp. To protect earthen structures from rising damp, a stone foundation was used, resulting in composite masonry. In the current study, an experimental investigation of the capillary absorption of non-stabilized CEBs produced with soils sourced from different areas of Cyprus, as well as of 2-layer composite building materials comprising of natural stone and CEBs was carried out. The tests on CEBs indicated that the use of water as the wetting liquid led to the disintegration of the specimens and consequently to non-linear response. Thus, a non-reactive liquid was used instead to measure the capillary absorption coefficient of the materials. The test results showed that the capillary absorption coefficient of CEBs varied between 140-260 gr/m²sec^1/2. In the case of the composites, capillary absorption with water as the wetting liquid showed perfectly linear response, following the t^1/2 law, with no disintegration of the specimens. The results showed that there are two distinct capillary absorption branches with different gradients, in line with the theory of capillary absorption into 2-layer composite materials.