Performance comparison between thin spray-on liners with different compositions

Abstract

Four thin spray-on liner (TSL) mixtures were produced and tested based on the performance requirements specified by EFNARC (2008). They generally showed good tensile and bond strengths; however, one powder-type TSL mixture was shown to be unsuitable as a permanent support member (a 'Class S' TSL), because its elongation at break was much lower than the EFNARC (2008) specification. Two-component TSLs consisting of a liquid polymer and a powder binding material were more ductile and generally performed better than the one-component powder mixtures. Their high ductility resulted in increased elongation at break, even though their tensile strengths were slightly lower than those of the one-component powder TSLs. One prototype two-component TSL produced here satisfied every criterion specified by EFNARC (2008). Notably, it increased the average compressive strength of mortar specimens by over 20% even when coated to a thickness of only 3 mm.

Synthesis and Properties of a Polymer‐Modified Material for Thin Spray‐On Liners in Mine Roadways

“…e TekFlfex prepared by Falconbridge Co., Ltd. (Toronto, Canada) is a kind of cement-based TSL materials [20,35,40]. Chang et al used an emulsion powder and cement to prepare TSL materials and changed the polymer content in the materials [41]. Due to the high ductility of the polymer, the ductility of the prepared composites was improved and the bending strength of the mortar specimen was enhanced by over 20%, while compressive strength of the prepared TSLs was simultaneously reduced.…”