الفهرس 
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Abstract
Field blasting experiments were carried out to investigate some factors affecting rock blasting.
Single hole blasting experiments were conducted in seven types of rocks. These experiments discussed the stemming length that may affect the rock breakage efficiency. Besides the optimum weight of change for one cubic meter in tested rocks were discussed. Also, some objectives corresponding to the output of the blast design such as fly rock and throw were measured. These are correlated with strength properties of tested rocks.
Carter blasting experiments were conducted in six types of rocks. These are to discuss the prediction of the burden distance in bench blasting in tested rocks. Also to predict the optimum depth of the charge for special blasting such as, ditching, trenching, and secondary blasting in the tested rocks.
The study of single hole blasting test, has shown the increase in optimum stemming length with decreasing compressive strength and modulus of rupture of rocks. The optimum stemming length has been found to range from 7 to 16 times the diameter of hole. Increasing compressive strength and modulus of rupture result in increasing specific charge (kg/m3). The expected throw and fly rock distances is more in hard rock than in soft rock. The range of maximum distance of throw has been found to range from 2 to 4 times the burden distance.
The tests of crater blasting has shown that, the crater dimensions (radius, depth, and volume) would increase with decreasing compressive strength and modulus of rupture. Also the optimum depth of the charge would decrease with increasing compressive strength and modulus of rupture. The optimum scaled charge depth has been found to range from 0.48 to 0.76.