Utilizing the Aggregate Impact Value (AIV) for the Indirect Determination of Uniaxial Compressive and Tensile Strengths in Weak and Altered Dacites

Abstract

Aggregates play a crucial role in geotechnical engineering, serving applications such as railway and road construction, hydraulic structures, and as the base material for concrete. While various tests are commonly employed to characterize aggregates, the Aggregate Impact Value (AIV) can also provide indirect information on fundamental rock properties. In this study, AIV was used to estimate Uniaxial Compressive Strength (UCS) and Brazilian Tensile Strength (BTS) for very weak, fractured, and altered rocks where preparing standard specimens is challenging or impossible. Statistical analyses were performed separately for two categories to support preliminary engineering assessments: weak rocks (dacite, limestone, lapilli tuff and claystone) (UCS < 50 MPa) and altered dacitic rocks. The results revealed a strong and statistically significant inverse correlation between AIV and both UCS and BTS across all categories. The coefficients of determination (R²) for the best-fitting regression models ranged from 0.87 to 0.94, indicating high predictive performance. Predicted UCS and BTS values based on AIV exhibited strong agreement with measured values, with correlation coefficients (r) between 0.90 and 0.96. These findings confirm the reliability of AIV as a predictive tool for mechanical properties in challenging rock environments. Overall, the proposed AIV-based regression equations provide a practical and efficient approach for preliminary assessment of UCS and BTS, offering valuable insight for geotechnical design when conventional sample preparation is difficult or infeasible.