Dynamic Response for Deep Buried Water Diversion Tunnel Under the Action of Near-Field Disturbance

The dynamic stress concentration ascribed to the scattering of stress waves encountering underground structures is an important factor affecting the damage of deep rock mass. A theoretical model was established in order to investigate the distribution of dynamic stress around a water diversion tunnel subjected to cylindrical P-wave resulting from near-field disturbance such as neighboring tunnel excavation and explosion in this study. Moreover, based on the steady-state solution of the wave function expansion method, the transient response around a circular lined tunnel with fully filled fluid subjected to half a sin wave with different incident times was derived. The calculation results indicate that waveform parameters, distance from disturbance source, lining thickness, and elastic modulus of lining materials have different degree effects on the distribution of dynamic stress concentration factor (DSCF) in rock and lining. Due to the presence of fluid, the distribution of DSCF would result in fluctuation phenomena when the wave number is large.