Alternative Approaches to Vibration Measurement Due to the Blasting Operation: A Pilot Study

Abstract

As the infrastructure grows, space on the surface in the urban area is diminishing, and the view of the builders is increasingly moving underground. Implementation of underground structures, however, presents a number of problems during construction. One of the primary side effects of tunnel excavation is vibration. These vibrations need to be monitored for potential damage to structures on the surface, and this monitoring is an integral part of any such structure. This paper brings an original pilot comparative study of standard seismic instrumentation with experimentally developed fiber-optic interferometric and acoustic systems for the purpose of monitoring vibration caused by the blasting operation. The results presented show that systems operating on physical principles (other than those previously used) have the potential to be an alternative that will replace the existing costly seismic equipment. The paper presents waveform images and frequency spectra from experimental measurements of the dynamic response of the rock environment, due to blasting operation performed shallowly during the tunnel excavation of a sewer collector. In the time and frequency domain, there is, by comparison, significant agreement both in the character of the waveform images (recording length, blasting operation timing) and in the spectra (bandwidth, dominant maxima).

Alternative Approaches to Measurement of Ground Vibrations Due to the Vibratory Roller: A Pilot Study

“…Image (a) corresponds to the time record made by the seismic station and Image (b) by the interferometric sensor. The manifestation of vibration compaction on time recordings had the typical character of this type of dynamic load [44] and was equally long for both devices. Furthermore, the recorded maxima amplitudes were noticeable always at the same time on the x-axis.…”

Comparative In Situ Study of Dynamic Load Generated by Gravel Piles Measured by a Fiber-Optic Interferometer

“…Two BRS32 seismic stations, see Figure 1 , were used as the reference instrument at two sites: these had also been used by the authors in previous studies aimed at comparing results obtained from alternative approaches to vibration measurement [ 1 , 6 , 8 ]. The special mobile compact datalogger had originally been developed for the Institute of Rock Structure and Mechanics of the CAS of the Czech Academy of Sciences, v.v.i.…”

“…The authors are building on the results of previous work. Papers [ 6 , 7 ] focus on monitoring vibrations caused by blasting or other sources of dynamic loading. This uses fiber-optic sensors in combination with conventional vibration measurement equipment.…”

Waveform Complexity and Positioning Analysis of Acoustic Emission Events during the Compression Failure Process of a Rock Burst Prone Sample

“…In previous studies, some experiments often overlooked the viewing of the original waveform and the optimization selection of algorithms and directly used the built-in software of the AE monitoring instrument for positioning, which lacked process analysis and affected the credibility of the positioning results [40]. The exploration and accurate processing of the original waveform is an important foundation for subsequent recognition and localization [41,42]. The quality of the original waveform directly determines the accuracy of event recognition and the method of picking up take-off points for event localization [43].…”