TITLE:
A New Method of Estimating Wave Energy from Ground Vibrations
AUTHORS:
K. Ram Chandar, V. R. Sastry
KEYWORDS:
Energy Distribution, Wave Form, Ground Vibrations, Seismic Energy
JOURNAL NAME:
Geomaterials,
Vol.5 No.2,
March
2,
2015
ABSTRACT: Performance of explosive
energy is rated in a number of ways, obtained either from theoretical
calculations or from experimental tests. However, it is difficult to determine
the amount of the explosive energy transferred to the rock and converted into
efficient work in the application of rock blasting. Although measurement of
some of the effects of explosive energy in rock mass is ground vibration,
noise, etc., which are usually conducted for blast control/analysis purpose,
the results are rarely used on energy content. Energy transferred to the rock
in the form of seismic waves is called seismic energy. In conventional analysis
of blast results, generally, the ground vibrations generated due to blasting
operations are monitored at a known distance from blast site with a
geophone/ground vibration monitor, in three mutually orthogonal directions.
Using such wave forms, an energy component is estimated from all the wave forms
in three directions, using a sophisticated signal processing software, which is
termed as “wave energy”. The wave energy is compared with the estimated seismic
energy. An investigating program was taken up involving 31 blasts conducted at
a hard rock excavation site to assess the influence of depth of excavation and
scaled distance on the seismic energy wasted in the form of ground vibrations.