Blasting operations are crucial for fracturing and breaking rocks in construction and aggregate processing. The bench height to burden ratio, also known as the stiffness ratio, plays a pivotal role in rock fragmentation. This study employs numerical simulations to investigate how this ratio influences fragmentation outcomes. Using a hybrid finite-discrete element method (FEM-DEM), the simulation integrates a Bonded Particle Model (BPM) for the rock media and a Particle Blast Method (PBM) to model blast loading during bench blasting. The simulations provide data regarding the mean particle size (d50), which is then analyzed in relation to the bench height to burden ratio to investigate their correlation. The findings indicate a noticeable pattern that with an increase in the bench height to burden ratio, there is a decrease in the mean particle size, which suggests more efficient rock fragmentation. This implies that higher ratios contribute to greater bench flexibility, thereby enhancing the effectiveness of fragmentation.