WIT Press


Interpretation Of Microseismic Effects From Response To Large Coal Mine Blasts

Price

Free (open access)

Paper DOI

10.2495/ERES110261

Volume

120

Pages

12

Page Range

309 - 320

Published

2011

Size

1,115 kb

Author(s)

C. H. Dowding & J. E. Meissner

Abstract

Response of a residential structure to ground motions generated by large, surface coal mine blasts can provide information regarding the cracking severity of microseismic events. Microseismic events produced by small earthquakes, minecollapse and reservoir induced seismicity, etc. can lead to concern on the part of those who feel the ground motion. These concerns can be addressed by reference to low frequency blast generated ground motions that have not caused cracking. This paper presents measured response of a structure to motions producing peak particle velocities of 10 to 19 mm/s and ground displacements of 0.3 mm at 5 to 15 Hz, which can be employed to interpret microseismic phenomena of any sort. Measured responses include velocity responses of the superstructure and midwall as well as vibratory response of existing cracks in walls. Response spectra of these blast generated motions are compared to those generated by moment magnitude five midcontinent earthquakes to determine the relative impact. The structure was inspected for crack extension after each blast and none were found Keywords: response spectrum, cracking, earthquakes, blasting, mining, micrometer, crack, response, humidity, temperature, climate, microseismic. 1 Response to large surface coal mine blast induced ground motions This article presents structural and crack response of a test house to unusually high amplitude, low frequency ground motions from surface coal mining. These measurements provide a comparison between excitation and structure response velocities and dynamic and long term micrometer crack response. Comparison of these mine-blast induced excitation ground motions with those produced by a

Keywords

response spectrum, cracking, earthquakes, blasting, mining, micrometer, crack, response, humidity, temperature, climate, microseismic