OFFICIAL Figure 4; Results obtained under intact rock conditions for packaged explosive diameters of 1 1/2" and 1 1/4", with a 1.8 m spacing and a 0.5 x 0.5 m grid. Illustration 7; Presplit filter results for 1.8 m spacing. CONCLUSIONS Based on the results of this study, the following conclusions are reached: • Modeling Framework: The analysis was conducted using numerical modeling, considering a rock mass with a GSI of 60% (Hoek, 2002). This necessitated the incorporation of structural planes consistent with this specific geomechanical condition. • Study Objective: This study represents a theoretical evaluation of various presplit design scenarios, analyzing the effects of varying both the borehole diameter and the packaged explosive diameter. • Optimal Configuration: When comparing the spacing scenarios, the highest presplit attenuation efficiency was achieved with a 1.2 m spacing and a 1 1/2-inch explosive diameter, reaching 48% according to the classification in Table 3. However, this design exhibited a larger fracture radius, indicating a greater impact on the rock mass compared to the 1 1/4-inch diameter, which recorded an efficiency of 39%. • Performance Limits: The lowest performance was observed at a 1.8 m spacing with a 1 1/4-inch explosive, where the presplit filter effect was only 18%. This was
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