论文部分内容阅读
延时爆破中延期时间的准确识别对于优化爆破设计和降低爆破振动效应具有重要作用。以超大断面调压竖井导井爆破为例,对比分析了基于Hilbert-Huang变换(HHT)的EMD识别法和瞬时能量识别法在精确短延时爆破中的延期时间识别能力,发现EMD识别法的识别率在80%以上,而瞬时能量法识别率低于25%。通过单孔爆破振动信号瞬时能量分析表明,瞬时能量识别法适用于延期时间大于瞬时能量峰值半周期的微差爆破。将EMD识别法应用于紫金山露天矿微差爆破延期时间识别,为降低爆破振动和爆破大块率,以识别结果为依据对爆破参数进行了优化。现场实测数据表明:通过优化起爆雷管和延期时间,相同单孔药量下爆破振动降低30%以上;结合压渣爆破和前排抵抗线优化,爆破块度成功降低到3%以下。研究结果证明了基于HHT的延期时间识别法能有效实现爆破设计的优化,该识别方法对于其他类似爆破工程的设计优化具有一定的参考价值。
Accurate identification of delay time in delayed blasting plays an important role in optimizing blasting design and reducing blasting vibration effects. Taking the example of mine shaft guide blasting with super-large cross-section pressure regulating shaft, the recognition ability of EMD based on Hilbert-Huang transform (HHT) and instantaneous energy recognition method in delay time of accurate short-time blasting are compared. The recognition rate is above 80%, while the instantaneous energy method recognition rate is below 25%. The instantaneous energy analysis of vibration signals of single-hole blasting shows that the instantaneous energy recognition method is suitable for the differential blasting whose delay time is longer than the half-period of instantaneous energy peak. The EMD method is applied to identify the delay time of micro-blasting in the open pit mine of Zijin Mountain. In order to reduce the blasting vibration and the mass rate of blasting, the blasting parameters are optimized based on the identification results. The field measured data show that blasting vibration can be reduced by more than 30% under the same single-hole dosage by optimizing the initiation detonator and the delaying time. Combining the slag blasting and the front line of resistance optimization, the blasting degree is successfully reduced to below 3%. The results show that the HHT-based delaying time identification method can effectively achieve the optimization of blasting design. The identification method is of certain reference value for the design optimization of other similar blasting projects.