Development Status of Thin, Spray-on Liners for Mining and Civil Engineering Applications

Research has been conducted for the Workplace Safety and Insurance Board of Ontario (WSIB) to characterize thin, spray-on lining materials (TSLs), as well as combinations of TSLs and conventional spray supports, and to assess their capacity for inhibiting damage created by mining-induced rockbursts. This study has been performed to assess the capabilities of such support systems for preventing rock and support material damage that often results due to rockbursting. A variety of TSLs and other spray support media were subjected to the effects of simulated rockbursting, through use of explosive detonation trials, to evaluate their damage mitigation capacity. Results have validated that TSLs and variant layer combinations may be as effective as or better than conventional support materials for mitigating rockburst or like damage in highly stressed mine environments. In civil engineering construction, and typically in underground tunneling operations where concrete linings are applied, liner deterioration is a continuing and pervasive problem that often requires expensive and time-consuming rehabilitation effort. The ability of TSLs to provide effective concrete structural reinforcement while providing sustainable resistance against underground or restricted environmental hazards, as with fires or dynamic failure events, may permit wider use of TSLs than is currently foreseen by the mining industry. Significant benefits for use of TSL materials in concrete liner rehabilitation and for concrete material protection have been assessed.