FEM Comparison of crack response to blasting ground vibrations and environmental changes

摘要

One of the negative effects of blasting at open pit mines is induced seismic wave or ground vibrations. These vibrations can in somecases have high magnitude and cause damage to the nearby structures. Those cases rise question of causal connection between blastingoperations and damage to structure, and hence blasters liability for damage.One of the approaches for solving this question is crack response monitoring which states that the causality exists if the cracks inthe structure respond to ground vibrations and if this response is higher than the response to other, non-blasting related factors.This article is the criticism of interpretation of crack monitoring results since even in those cases when blasting influence isconsiderably smaller than other influences it can not, and should not be neglected because is the fact that it exists.A FEM analysis is used to compare crack responses to blasting ground vibrations and environmental influences considering the stressstate (expressed by stress intensity factor) around the crack tip and to determine equivalent crack responses in the form of crack opening.