Study on Efficient Well Formation by Digital Electronic Detonator Deep Hole Blasting in Loose and Soft Rock Body

To address the low efficiency, poor safety, and high costs associated with traditional segmental blasting in soft rock conditions, research is conducted on high-efficiency deep-hole blasting techniques using digital electronic detonators. Taking the No. 6 cutting shaft at the Beizhan iron ore mine as the engineering context, an innovative two-stage upward-directed deep-hole rapid shaft sinking blasting plan is designed for the 19.3-meter-deep cutting shaft in soft, fractured rock. Through theoretical calculations, key blasting parameters are determined, including a 50-millisecond inter-hole delay and a 300-millisecond inter-layer delay. A large-diameter empty hole (127 mm) is utilized as a compensation space, with a charge hole diameter of 76 mm. The blast hole layout and initiation sequence are rationally designed. Field test results demonstrate: the top surface remains well-defined after blasting, with good roof integrity and uniform block size. The measured height meets design requirements. Technical-economic analysis reveals: compared to conventional tunneling methods, deep-hole blasting reduces costs by 53%, saves 6 days of construction time, and significantly improves operational efficiency. The two-stage blasting approach effectively minimizes frequent disturbance to the fractured rock mass, preventing rock falls. Combined with precise detonation control using digital electronic detonators, this method substantially enhances operational safety.