Research On The Safety Technologies Of Deep-hole Bench Surface Blasting

As the increasing number of the open-pit blasting mining, the blasting safety has attracted more attention. The present technologies can’t satisfy the requirement of the safe blasting on a large scale. It is necessary to seek an optimal design to improve the current situation. As the rock blasting theories and computer simulation technologies developing, the research method has become increasingly diversified. In this paper, the mechanism of deep-hole bench surface blasting was analyzed on the basis of rock blasting theories. An optimized design of hole network parameters in the existing blasting parameters of metal mine was carried out and a suitable parameters was obtained by LS-DYNA. We also analyzed the different effects of blasting methods on the blasting of metal mine. The issue of damping ditch was raised and studied to reduce the blasting vibration. The proposed schemes were simulated, analyzed and verified. The experimental results are shown as follows:The theory of deep-hole bench blasting and the process were studied, and the theoretical foundation of the parameters selection was also analyzed. The theories above could support the designs below.An actual test, with the blasting parameters from a certain mine, was carried out, and the corresponding practical situation was simulated. The authenticity and reliability of simulated results were confirmed by comparing the actual results with the simulated results.Considering about the problem of toe rock and boulders in blasting tests, parameters with larger spacing and smaller row spacing than existing pattern parameters have been designed to improve the blasting effect, and then the relevant numerical modeling has been done. The result shows that the new hole pattern parameters can decrease the toe rock and boulders effectively.In order to figure out the uneven blasting caused by different components of various kinds of rock, some new detonate styles has been tested in combination with the effect analysis of the frequently-used detonate style at hole-bottom. Three detonating modes including detonated at hole-bottom, hole-center and the two areas synchronously were simulated and evaluated. As results, the selection basis of different initiation ways according to various rocks has been obtained.The designs of damping ditch were proposed to solve blasting vibration, which were thought as the most serious one in blast damages. Based on the test data mentioned above, different effects of different parameters on vibration reduction in protected areas were studied, which include the depth of damping ditch and the distances from blasting center. Thus, a better solution project has been obtained.The optimization of the blasting parameters and the protection of blasting vibration damage can make the exploitation of mines safely and reliable, which can ensure economic benefit maximization. The conclusions above can be used as the guidance for the exploitation of similar mines.