ABSTRACT
The paper theoretically investigates the induced buckling mechanism of pillar rockbursts in hard rock mines from an innovative point of view, by considering rockbursts as a dynamic instability problem of underground structures. New findings include: (1) a new explanation for the “sudden and violent” aspect of rockbursts, characterized by exponential growth of the amplitudes of transverse displacement responses, even in the presence of rock damping; (2) identification of the critical role in inducing rockbursts of dynamic loadings that bear frequencies approximately double the natural pillar frequency; (3) the greater influence on rockburst occurrence of the amplitude of the dynamic component relative to the static component of loadings; and (4) quantification of the relative effects of stress waveform of dynamic loadings on pillar rockbursts, which are in decreasing order: rectangular, sinusoidal, and exponential waveforms. Application examples are provided and limitations of the approach are discussed. In contrast to conventional methods that use rock specimens to study rockbursts, this investigation emphasizes the structural effects on rockbursts, which has strong potential applications in practical hard rock mining engineering.
