Micro-drilling resistance measurement: A New technique to estimate the porosity Of a building stone

Abstract

This study aimed to find the relationship between the drilling resistance (DR) of a stone and its porosity. 40 sandstone and limestone samples (20 each lithotype ) were taken into consideration in this study. The samples were mineralogically and petrographically investigated using X-ray diffraction (XRD) and polarized light microscopy. The sandstone samples were identified as quartz arenite that is composed of Quartz, Kaolinite and Calcite, while the limestone samples were identified as micritic limestone that is composed of Calcite. The average DR of the samples was measured using a Drilling Resistance Measurement System (DRMS), and the porosities were determined using a RILEM standard test method. A mathematical relationship between the DR and porosity was derived for both stone types. It was found to be a linear inverse relationship in both cases. The derived relationships were used to calculate the porosities of additional sandstone and limestone samples based on their measured average DR. The values of calculated porosities showed acceptable accuracy when compared with measured values. Therefore, this technique is recommended to estimate the porosity of stones with similar mineralogical compositions.