Abstract
Rock bursts occur frequently in coal mines, and the mechanical properties of saturated coal specimens under coupled static‐dynamic loading need to be studied in detail. Comparative tests of coal specimens having different water content under static and static‐dynamic loading are conducted using the split Hopkinson pressure bar (SHPB) and RMT‐150C test systems. The results demonstrate that the natural specimen strength is greater than that of seven‐day (7D) saturated specimens under both uniaxial compression and triaxial static compression loading; however, the dynamic strength of 7D saturated specimens is lower than that of natural specimens under one‐dimensional static‐dynamic loading. The particle size of the 7D saturated specimens is relatively small under uniaxial static compression and one‐dimensional static‐dynamic loading, and the specimen particle sizes before and after static triaxial loading tests and three‐dimensional static‐dynamic loading tests do not exhibit an obvious difference.
Highlights
Geotechnical engineering practices, such as mining, slope stability, and water conservation, are significantly affected by water
Huang et al [12] studied the mechanical properties of saturated sandstone tensile strength under dynamic loading in split Hopkinson pressure bar (SHPB) system, and the results indicated that the tensile strength softening factor decreases with the loading rate
As coal contains multivoids and multicracks, under triaxial static loading, the coal strength and deformation behavior are affected by saturation conditions to differing extents, and water has an obvious softening effect on cracked coal specimens
Summary
Geotechnical engineering practices, such as mining, slope stability, and water conservation, are significantly affected by water. Few studies exist on the strength and failure characteristics of water-saturated coal specimens under impact, and the results of such an investigation are helpful in preventing rock burst. Numerous research studies have been conducted on the mechanical properties of rock under dynamic loading at different strain rates [11]. Huang et al [12] studied the mechanical properties of saturated sandstone tensile strength under dynamic loading in SHPB system, and the results indicated that the tensile strength softening factor decreases with the loading rate. Static and dynamic loading strength tests of sandstone under different water bearing conditions were carried out in SHPB system by Zhou et al [14, 15], revealing that the static and dynamic sandstone strengths decreased by 29.88% and 40.55%, respectively, following saturation. The results provide theoretical and engineering guidance for rock burst prevention in coal mines
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have