<p>Open-pit mining has the advantage of high efficiency and large scale, but its production capacity is often restricted by fluctuations in uniaxial compressive strength (UCS). Traditional UCS assessment methods, such as laboratory tests and on-site tests, are time-consuming and labor-intensive, making it difficult to meet the real-time needs of engineering projects. To address this issue, this paper proposes a real-time rock UCS assessment method based on the operating parameters of rotary drilling rigs. Specifically, the method first simulates the rock-breaking process of rotary drilling rigs using the discrete element method (DEM), capturing the interaction between parameters like drilling pressure and torque and UCS response. Then, based on mechanical mechanisms, it puts forward the rock strength index (RSI), establishes a quantitative relationship between the key parameters of the drilling rig and UCS, and overcomes the limitations of traditional empirical regression methods. During on-site verification, it was found that RSI and UCS show a strong linear correlation, and the real-time inversion error of UCS is less than 10%. Based on this result, this study further developed rock mass strength zoning technology and generated spatial distribution maps, which provide direct guidance for optimizing blasting design and adjusting ore blending plans in mining areas. This method reduces the UCS assessment time from the traditional several days to the minute level, effectively improving the stability of ore powder production capacity. It also provides a practical technical solution for real-time monitoring of rock mass strength and production capacity optimization in open-pit mining.</p>