The strength behavior of rocks is a question of complex determination. The Hoek–Brown failure criterion for rock masses is the currently accepted solution to this problem and has been applied to a large number of projects worldwide. However, the estimation of Hoek–Brown parameters is directly dependent on complex and time-consuming tests (e.g., triaxial tests), demanding excessive investments, and complicated analysis. This paper proposes a method to calculate the Hoek–Brown parameters and derive the nonlinear failure envelope of distinct types of artificially cemented materials (where the integrity of the samples is ensured), comparing these results with real laboratory data. The method utilizes basic tests, such as unconfined compression tests and Brazilian tests, to estimate the maximum shear strength of materials in triaxial tests with effective confining pressures up to 400 kPa. The proposed methodology presents an accurate and conservative fit for the experimental strength results, indicating the applicability of the approach to a wide range of artificially cemented materials without the need to perform triaxial tests or any other elaborate and time-consuming procedures.