INVESTIGATION OF MINI-BENCH BLASTING APPLICABILITY AND GROUND VIBRATION EFFECTS AT THE EXCAVATION FOR FOUNDATION IN SETTLEMENT

Abstract

Today the need for housing, transportation, and infrastructure has become more pressing due to rapid urbanization and population increase. In subway, infrastructure, and housing constructions, blasting excavations are required because of the hardness of rocks on the ground surface and underground. The aim of this paper is to demonstrate the feasibility of the method of mini bench blasting during foundation excavations on hard rock units in settlement areas. In order not to damage buildings surround the foundation excavation area of Government Project. It is argued that mini bench blasting shots can be applied in foundation excavations in settlement areas without any risks. Within the scope of this study in order to predict peak particle velocity level for this site, ground vibration components were measured for mini bench blasting. In blasting operations; ANFO (blasting agent), gelatin dynamite (priming) and delay non-electric detonators (firing) were used as explosives. Parameters of scaled distance (charge quantity per delay and the distance between the source and the station) were recorded carefully and the ground vibration components were measured for all blast events. Then, the data pairs of scaled distance and particle velocity were analyzed statistically. At the end of statistical evaluation of the data pairs, an empirical relation which gives average line at 50% confidence level and upper bound 95% prediction line with a reasonable correlation coefficient was established between peak particle velocity and scaled distance.