Control Effect of Negative Poisson's Ratio (NPR) Cable on Impact-Induced Rockburst with Different Strain Rates: An Experimental Investigation.

Impact-induced rockburst hazards pose a severe threat to the construction safety of deep-buried, high-stress tunnels. Negative Poisson's ratio (NPR) cable has the characteristics of strong energy absorption and impact resistance. In order to explore the control effect of NPR cable on impact-induced rockburst, this paper designed and developed a model NPR cable based on the similarity principle. With the help of the self-developed new true triaxial rockburst experimental apparatus, indoor simulation experiments of rockburst under dynamic disturbance at varying strain rates were conducted. The rockburst characteristics under the conditions of NPR cable support were compared to those without support. On rockburst, the influence mechanism of strain rate and NPR support was discussed. The results indicate that the rock strength and rockburst intensity increase as the strain rate of dynamic disturbance increases. The support of NPR cables enhances energy dissipation and rock fragmentation, as well as increases the strength of the rock. Importantly, with NPR support, the energy release rate during rock failure slows, which significantly minimizes the rockburst intensity (kinetic energy release). The research results provide reference and guidance for the engineering practice of rockburst control. Highlights: A cable model with negative Poisson's ratio (NPR) structure effect was developed and its mechanical properties were verified. The experiments of rockburst caused by dynamic disturbance with different strain rates were carried out, and the situation with or without NPR support was compared. With the increase of strain rate of dynamic disturbance, rock strength and rockburst intensity increase. NPR cable improves rock-bearing capacity and effectively reduces rockburst intensity by enhancing fracture and reducing energy release. [ABSTRACT FROM AUTHOR]