• Dynamic compressive strength of self-swelling cartridges (SSCs) increases with density, decreases with insertion gap, and shows a non-monotonic trend with water absorption, with density being the most significant factor.
• SSCs exhibit pronounced strain-rate strengthening: both peak stress and peak strain increase quadratically with strain rate, and fragmentation, absorbed energy, and dynamic increase factor all rise with strain rate.
• Compared to cementitious stemming materials, SSCs prolong the duration of gas explosion action, making them more effective for blasting stemming and rock burst control.
• The study provides quantitative insights for optimizing SSC composition and application in high strain-rate rock blasting scenarios.