Mineralogical, physico-mechanical, and durability characteristics of limestone: Quality assessment and empirical prediction of compressive and tensile strengths

The limestone is widely used as a building stone in engineering structures and historical monuments. Accurate assessment of the engineering behavior of limestone is challenging due to its inherent characteristics' variability. The present study addresses this challenge by providing an integrated experimental characterization of the various characteristics of limestone, including the mineralogical composition, porosity (n), uniaxial compressive strength (UCS), Brazilian tensile strength (BTS), point load index (PLI), P-wave velocity (Vp), and slake durability index (SDI). To this end, the limestone samples were collected from the various areas of Khorramabad city. The mineralogical composition, n, UCS, BTS, PLI, Vp, and SDI of the samples were determined. A new quantitative-qualitative ranking framework using these characteristics was proposed to classify the engineering quality of the limestones, which enables practical decision-making in construction and geotechnical design. Moreover, predictive equations of UCS and BTS using n, PLI, Vp, and SDI were established. According to the quantitative-qualitative ranking, the samples have different suitability for use as a construction material. The findings of the regression analyses showed that the UCS and BTS of the studied samples can be predicted using n and Vp with good accuracy, whereas there are weak correlations between UCS and BTS with the PLI and SDI. Although results indicated that the predictive equations of the UCS are generalizable to limestones from other regions of the world, the predictive equations of the BTS yielded significant prediction errors (PE > 28 %) and are therefore restricted to preliminary assessments of the samples in the present study.