Tear tests of glass fibre reinforced polymer skin spray-on liner

Current research into strata support automation in coal mine roadways requires development of a strong, tough and effective skin support that can be applied remotely. To investigate suitability of a glass fibre reinforced polymeric thin Spray-On Liner (TSL) numerous small and large scale samples were tested. These tests include; the tear load due to the lateral movement of TSL to fail in tear through the bolts installed in underground roadway roof, and the ‘truser tear’ due to the differential movement of the supported strata. The laboratory experiments suggested that a polymer based TSL can withstand substantial tear loads and despite the tear failure, the remaining TSL sheet can maintain strata support effectively. The tear strength tests were conducted using a standard 22 mm diameter steel bolt tearing the 5 mm thick polymer sheets reinforced with two or three glass fibre layers. The trouser tear tests were conducted with two and three layers of glass fibre reinforcement. The bolt tear tests indicated load bearing capacities in the range of 7.4 to 13.8 kN depending on the amount of reinforcement, while the trousers tear strength ranged from approximately 0.4 to 1.1 kN.