ارائه مدل تجربی پیش‌بینی متوسط ابعاد خردشدگی حاصل از انفجار در توده‌سنگ کنگلومرای سد گتوند علیا

The main aim of blasting operations in mining and civil engineering projects is size reduction of the rock-mass. Particle size reduction (P.S.R) affects the efficiency of the loading, haulage and milling equipments. Therefore, prediction of mean fragment size in designing optimum blasting patterns is crucial. In this research, a model is presented for predicting mean fragment size caused by blasting, using a combination of Grady & Kipp model (considering the number of radial cracks in the vicinity of the blast-hole) and concept of the mean fragment size. The proposed model shows that mean fragment size is a function of rock-mass characteristics, fracture toughness (KIC), explosive characteristics such as velocity of detonation, specific density and geometrical blasting parameters like burden, spacing, blast-hole diameter, etc. Considering validation of this model at the rock-fill mines of Gotvand Olya Dam, in real-scale, application of this model is recommended in open-pit mines blasting.