A new dynamic fracturing method: deflagration fracturing technology with carbon dioxide

Control of damaged zone caused by impact load is the challenging issue in blasting engineering. In this paper, a new rock breaking method using carbon dioxide ice powder is developed, which is characterized by weak disturbance. Then experiments on the CO2 pneumatic fracturing of concrete specimens were conducted. Generally, the CO2-driven fracturing process generates medium strain rate ((epsilon) over dot = 10(0) to 10(1) 1/s), the large concrete specimen was fractured into 3-5 blocks, and no crushing damage occurred. The transient failure modes in the shock wave event were discussed, and the fragment size-strain rate relationship was established based on the cusp mutation theory. The theoretical calculation results are consistent with the experimental results. The research achievement may provide a new and safe rock-fracturing method for geological engineering.