Akademik Veri Yönetim Sistemi
Iranian Journal of Science and Technology - Transactions of Civil Engineering, cilt.49, sa.1, ss.487-501, 2025 (SCI-Expanded)
The strength conversion factor (k) and the strength ratio (R) are defined as the ratios between the uniaxial compressive strength (UCS) / the point load index (PLI) and UCS / tensile strength (BTS), respectively. k and R have been used to estimate the UCS of rocks for almost 50 years. However, research on basaltic rocks’ k and R coefficients is still limited. Additionally, few studies have investigated the k and R coefficients for concrete, which is more homogenous than rock samples. Therefore, this study aims to determine k and R coefficients for basaltic rocks and concrete samples produced from the same rocks’ aggregates for different curing times. In this study, basaltic rocks’ average k and R values were 17.1, and 10.4, respectively. Furthermore, statistical analyses showed that k coefficients may vary in the range of 17–20 according to the 84 samples of basalts (vesicular, amygdaloidal, massive, olivine augite basalt, etc.) collected from the literature. However, according to the literature, k values for basaltic rocks were distributed in a narrower range than those found in other rocks. The average k and R values for all concrete curing times were obtained as 8.2 and 5, respectively. These coefficients are approximately twice as high in rock samples as concrete ones. The equations proposed are very significant, especially at the preliminary design stage of geotechnical works, since the uniaxial compressive strength of rocks (UCS-R) and uniaxial compressive strength of concrete (UCS-C) can be roughly forecasted with caution for basaltic rocks having similar properties.