User:Rainaji
From Wikipedia, the free encyclopedia
FLYROCK: An unwanted or undesired exceptionally excessive throw of rock fragments from blasting that may cause damage to structures, animals and humans nearby a blast site. The reasons may be due to improper blast design or underlying geological features that were not taken into account while blasting.
There are several controllable blast design parameters that may be responsible for flyrock occurrence. These include Burden, Stemming, Charge Length, Charge Concentration, Hole diameter or Charge diameter. In uncontrollable parameters, the major factor is the joint spacing alongwith features that may restrict or favour flyrock generation - including weak beds in competent rock, voids or gaps in the formation etc.
The Flyrock phenomenon is a Random one and needs to be evaluated by statistical probability. A Risk based Flyrock criterion has been devised by Raina et al., 2006 which uses a "Factor of Safety" for flyrock and Threat Ratio - Defined by the distance of Object of Concern to the Permissible distance of Flyrock.
