Engineering

Gas explosion

Aerospace engineering

Geotechnical engineering

Metallurgy

Materials science

Dynamic load testing

Dynamic loading

Gas pressure

Petroleum engineering

Coal mining

Bar (unit)

Dynamic testing

Projectile

Geology

Coal

Oceanography

Dissipation

Waste management

Thermodynamics

Split-Hopkinson pressure bar

Physics

Dynamic pressure

Static pressure

Dynamic range compression

Composite material

Structural engineering

Compression (physics)

Forensic engineering

Light-gas gun

Coal gas

Strain rate

Compressive strength

Rock Mechanics and Rock Engineering

In deep mine, coal is usually subjected to coupled high gas pressure and static compressive stress. The coal may be also subjected to dynamic loading due to the sudden fracture of hard roof during mining. In our previous study, the behaviour of gas-containing coals with initial gas pressure was investigated subjected to uniaxial static compression. In this study, the dynamic compressive behaviour of gas-containing coals with gas pressure and static axial preloading is investigated using a modified Split Hopkinson Pressure Bar (SHPB) system. The dynamic behaviours of gas-containing coals under SHPB tests are studied by varying initial gas pressure and axial static preloading. The testing results include strain measurements and energy dissipation. In addition, the wave impedance method is used to quantify damage of gas-containing coals under coupled gas-static-dynamic load. It is found that the dynamic compressive strength of gas-containing coal under coupled load decreases with the increasing initial gas pressure. The gas-containing coal with higher gas pressure and axial static preloading is more vulnerable to dynamic loading. The findings can be applied to mining design or support design in deep mining of high-gas-containing coal seam.

Dynamic Compressive Test of Gas-Containing Coal Using a Modified Split Hopkinson Pressure Bar System