Influence of Water Saturation on Mechanical Properties of Porous Building Stones

Abstract

Currently, rock materials are principally used in the construction of emblematic buildings, ornamental elements, retaining systems or as replacement material of architectural monuments. Nevertheless, despite most these constructions are commonly in moist environments or in direct contact with water, standard tests determine rock mechanical properties under dry conditions, after removing water content in an oven. Furthermore, it is well known that moisture is a key ingredient in the strength of some rocks. These points mean that there is a need to study in more detail the effect of water content on mechanical properties of building stones. The objective of this research was to quantify the effect of water saturation on strength and deformability of porous building stones from the province of Alicante. To this aim, cylindrical specimens of three Bateig varieties were prepared and the bulk and real densities, open and total porosities, water absorption and P and S wave velocity were determined according to UNE Spanish standards. Subsequently, for each variety of building stone, half of the samples were dried in an oven at 105 ºC to obtain dry samples and the other half were soaked in water inside a vacuum chamber to fully saturate them. Finally, all samples were tested in laboratory in order to determine the mechanical properties under dry and saturated conditions. The results showed a very significant reduction of unconfined compressive strength, Young modulus and point load strength index, so it is necessary to consider the saturation effect when these stones are exposed to water during its lifetime.