Finite Element Modeling of Stress Distribution And Stability in Underground Haulage Ways: A Case Study From The El Descanso Mine, Cuba

Abstract

Underground haulage ways are critical horizontal routes for transporting workers, materials, and ore in mines. Excavation and blasting-induced vibrations can weaken the surrounding rock mass and lead to instability. This study evaluates the geomechanical stability of a haulage way at the El Descanso mine (central Cuba) to determine optimal support requirements. Field mapping and laboratory testing (ISRM and ASTM standards) characterized the dominant serpentine and gabbro rock masses. Two-dimensional and three-dimensional finite element models were developed in Phase2V6 (RS2) using the Mohr–Coulomb and generalized Hoek–Brown criteria. In the unsupported model, the maximum principal stress was 0.33 MPa, maximum displacement 0.26 mm, and minimum resistance factor 1.83. Supported models (anchors + shotcrete) showed slightly higher localized stresses (0.99 MPa), but remained well below rock-mass strength. No widespread zones of destruction formed, and displacements were negligible compared to the 10% excavation-radius stability threshold (~110 mm). The results demonstrate that the excavation is inherently stable due to competent nature of the massive ophiolitic rock mass, and that heavy artificial support is geomechanically unnecessary, validating current practice and offering potential cost savings. This site-specific FEM approach fills a data gap for serpentine–gabbro tectonic suture zones and highlights the value of hybrid 2D/3D modeling for support optimization.