Design of Factor of Safety based Criterion for Control of Flyrock/Throw and Optimum Fragmentation

摘要

Rock fragments that are propelled to unwanted distances due to improper design or unforeseen rock mass conditions are known as flyrock. Flyrock is the most hazardous phenomenon in blasting as these pose threat to personnel and property both outside and inside a mine. Prediction of flyrock has been a difficult proposition owing to its random and probabilistic nature. An attempt was made to define the conditions and design of a criterion that could not only define the throw hut the safety conditions of flyrock or throw, also. This paper defines a factor of safety for evaluating the safety conditions in respect of throw and flyrock. Simple to determine design and rock factors have been proposed to ease the calculations and a criterion for defining safe throw in relation to fragmentation.