Laboratory Investigation of Support Mechanism for Thin Spray-on Liners

ABSTRACT: Rock support is the basis of any underground mine and many open cut operations. Ground support methods have evolved over the years with the current trend to use bolts, mesh and shotcrete. Thin spray-on liners may be the next step replacing mesh and shotcrete, however being a relatively new product is not well understood and no standard testing procedures exist to determine the strength of the individual products. Many methods of testing have been proposed by different researchers and many different tests have been conducted covering the majority of these methods. Yet little follow up research has been done on these tests and little is known of the repeatability and the results of these tests and whether the tests can be used as standard testing procedures or whether they are unfeasible. A series of tests were undertaken to determine what would be the appropriate testing procedures. The test conducted were a bending test, double sided shear strength and coated core samples. Sandstone samples were used as it is a very uniform rock giving more consistent results. All the tests produced promising results into whether they should be standard testing procedures or not.