Impact-induced failure and mechanical response of rapidly solidified sealing materials for blast holes

This study addresses the challenge of inadequate hole sealing in the drill-and-blast method, which often results in suboptimal blasting performance, by investigating the development and mechanical behavior of sealing materials through theoretical analysis and laboratory testing. First, the formation mechanism of caliche is analyzed, leading to the creation of a stable, fast-setting single-slurry sealing material suitable for pumping applications. Second, a dynamic friction strength model is developed to characterize the sealing performance of the material, based on principles of material and friction mechanics. Furthermore, key factors influencing sealing strength are systematically identified. Finally, the mechanical response of the materials is evaluated under various conditions using static compression tests and Split Hopkinson Pressure Bar (SHPB) impact tests, offering a systematic framework for evaluating the material’s behavior under both quasi-static and high strain-rate conditions. The results indicate that sealing length has a more pronounced effect on sealing properties than the material’s age. Furthermore, as impact air pressure increases, the sealing material undergoes a failure transition from brittle fracture to plastic deformation, demonstrating enhanced damage resistance under high strain rate conditions. This study also reveals previously unquantified effects of sealing length and impact loading on failure behavior, providing new insights into the material’s dynamic failure resistance and sealing efficiency optimization. These findings not only enhance the sealing quality of blast holes but also provide valuable insights into mechanized sealing technology, offering significant implications for engineering applications.