A New Method to Assess Coal Burst Risks Using Dynamic and Static Loading Analysis

• Published in: Rock mechanics and rock engineering Vol. 53; no. 3; pp. 1113 - 1128
• Main Authors: Wang, Changbin, Cao, Anye, Zhang, Chengguo, Canbulat, Ismet
• Format: Journal Article
• Language: English
• Published: Vienna Springer Vienna 01.03.2020; Springer Nature B.V
• Subjects: Attenuation; Civil Engineering; Coal; Coal mines; Dynamic loads; Earth and Environmental Science; Earth Sciences; Earthquakes; Energy; Energy resources; Energy sources; Geophysics/Geodesy; Longwall mining; Mechanical loading; Mining; Orbital velocity; Original Paper; Risk; Risk assessment; Seismic activity; Seismic energy; Seismicity; Seismograms; Tomography; Velocity; Coal burst; Passive velocity tomography; Energy attenuation; Dynamic and static loads; Seismic monitoring
• ISSN: 0723-2632; 1434-453X
• DOI: 10.1007/s00603-019-01968-5

Mining-induced seismicity is one of the dynamic energy sources that can trigger coal burst. This paper presents a new methodology to assess coal burst risks under different loading conditions by examining seismic energy attenuation and fracture size. Two new indices are proposed: (1) Dynamic Load Index (DLI) quantifies the magnitude of dynamic loading induced by seismic events, based on the relationships between the seismic energy, peak particle velocity and dynamic stress; (2) dynamic–static loading assessment index, I PD , links the DLI with passive velocity tomography (PVT) to assess the coal burst risks in a longwall panel under dynamic and static loading. A total of 3080 seismic records were examined to validate I PD in a typical burst-prone longwall panel in China. Based on the rate of occurrence of high-magnitude seismic events, I PD thresholds were determined to identify low-, medium- and high-risk coal burst zones. Using this new zoning approach, coal burst risks were assessed in the same longwall panel while mining through a fault structure. The proposed risk classes correlated well with the recorded high-magnitude seismic events with energies over 10 kJ. The analysis indicated that 69% of the high-magnitude events occurred in the high-risk zones, where I PD was between 0.35 and 1; and 31% of the events occurred in the medium-risk zones, where I PD was between 0.2 and 0.35.