Abstract:

Sound velocity variation is the valid parameter as the token of damage variance. In order to discover the blasting damage cumulative effect and the damage evolutive law of rock mass, sound wave measurement for surrounding rock damage under blasting time after time was carried out at some underground engineering; and the data regression was analyzed at the same time. The corresponding relation between rock mass damage and sound velocity variation under several times blasting was analyzed; and the cumulative expanded models of rock mass blasting damage with the baseline of rock mass sound velocity reducing ratio were founded. Research results show that the correlation coefficient of regression analysis is more than 0.981 6, which illuminate the nonlinear cumulative regression forecast models of rock mass blasting damage founded by test results are correct. The final quantity of rock mass damage is the total of initial damage and blasting damage in the cumulative expanded models of rock mass blasting damage, and where the influences of blasting cumulative damage effect and initial damage are synthetically considered. So the models can reflect the damage degree of rock mass veritably, which are reasonable and feasible.

Key words: blasting, sound velocity variation, regression analysis, cumulative damage models