关键词: 地下洞室, 深孔台阶爆破, 孔内分段, 线性叠加, 爆破振动, 延时间隔

Abstract: To address the issues of large single-hole charge quantity and difficult vibration control in deep-hole bench blasting of underground caverns， a method combining the in-hole segmented loading structure with the Anderson wave superposition principle is adopted. On the basis of reducing the single-segment charge quantity and increasing the utilization rate of blast holes， the optimal in-hole interval loading millisecond delay initiation and the inter-hole delay initiation time difference are obtained， which maximally reduces the vibration generated by deep-hole bench blasting in underground caverns. Through insitu single-hole in-hole segmented loading structure blasting tests， the single-segment blasting vibration waveforms of the upper and lower loading sections of a single hole are obtained. The single-segment waveform functions of the upper and lower sections are determined by fitting the measured single-segment waveforms using MATLAB. Different single-segment waveforms with different charge quantities are reconstructed， and the complete single-hole blasting vibration waveforms are obtained by superimposing the two waveforms at different in-hole delay intervals. The in-hole delay interval corresponding to the waveform with the minimum peak value is the optimal in-hole delay interval. Then， the single-segment waveforms of all blast holes in the blasting area are linearly superimposed at different inter-hole delay intervals to obtain the quantitative relationship among the delay interval， charge quantity， and the peak value of the multi-hole superimposed waveform. The optimal solutions for the in-hole delay interval and the inter-hole delay interval are solved. Through verification tests and field tests， when the blast center distance is 331 m， the optimal charge quantities of the upper and lower sections of the in-hole segmented loading structure for deep-hole bench blasting in underground chambers are calculated to be 11.7 and 12.6 kg respectively， and the optimal delay intervals of the electronic detonators for in-hole and inter-hole are 6 and 50 ms， respectively. The blasting vibration peak values could be controlled to the minimum， with the predicted values being 0.11 and 0.25 cm/s respectively， which differs by 4% from the measured values， verifying the feasibility and accuracy of the proposed method.

Key words: underground cavern, deep-hole bench blasting, in-hole segmentation, linear superposition, blasting vibration, delay interval