Determination of anisotropy to enhance the durability of natural stone

Abstract

Anisotropy is a petrophysical property of natural stone and other construction materials thatdetermines their quality and resistance to decay due to a variety of agents, such as water. A studywas conducted on nine types of stone widely used in Spain’s built heritage, using six previouslydefined anisotropy indices. These indices can be used to determine the degree of anisotropy,which helps explain the differential decay observed in stone materials quarried in the same bedand used to build the same structure. The conclusion reached is that anisotropy should bedetermined in the natural stone used both to restore the architectural heritage and in newconstruction, since the appropriate choice of material quality ensures greater resistance to decayand, therefore, increased durability. Materials with the lowest possible anisotropy should beselected, as this property governs their hydraulic behaviour: the lower the anisotropy in amaterial, the better its behaviour in relation to water and the longer its durability.