Experimental study on prediction model for maximum rebound ratio

The proposed prediction model for estimating the maximum rebound ratio was applied to a field explosion test, Mandai test in Singapore. The estimated possible maximum peak particle velocities(PPVs) were compared with the field records. Three of the four available field-recorded PPVs lie exactly below the estimated possible maximum values as expected, while the fourth available field-recorded PPV lies close to and a bit higher than the estimated maximum possible PPV. The comparison results show that the predicted PPVs from the proposed prediction model for the maximum rebound ratio match the field-recorded PPVs better than those from two empirical formulae. The very good agreement between the estimated and field-recorded values validates the proposed prediction model for estimating PPV in a rock mass with a set of joints due to application of a two dimensional compressional wave at the boundary of a tunnel or a borehole.     

Numerical study on maximum rebound ratio in blasting wave propagation along radian direction normal to joints

1 INTRODUCTION For one dimensional wave, such as seismic wave, passing across single joint or multiple parallel joints, combining the theory of displacement discontinuities and the method of characteristics, solutions in terms of magnitudes of the reflection ratio and the transmission ratio have been obtained by several researchers[1?6] for P-wave and S-wave respectively. However, for a practical dynamic problem in a rock mass involving blasting wave propagation from a tunnel or borehole,…