Mechanistic investigation of shotcrete as rock support: Interpretation and numerical modelling of field test results

Shotcrete is used extensively in Canadian mines for a wide variety of applications, including infrastructure construction, backfill barricade creation, and primary and secondary ground support. Currently, the design of shotcrete support systems relies mostly on empirical methodologies coupled with shotcrete experience, if any, from within the specific mine. Unfortunately, this provides little opportunity for factor-of-safety estimation and support optimization. Laboratory tests are used to quantify strength parameters and material properties, but the values are mostly used for mix comparison. The transfer of knowledge from the laboratory to in situ design has been slow.; This research was undertaken to increase the understanding of shotcrete behaviour, and particularly focused on shotcrete failure during a relatively new testing methodology called the large-scale in situ pull test. The research comprised three main units: a field testing program to gather data and study the logistics of the test methodology; generation of two-dimensional numerical models to facilitate the transfer of knowledge from laboratory tests; and generation of a three-dimensional numerical model to be used as a tool to understand how various parameters affect the behaviour of shotcrete and to aid in the interpretation of results from the large-scale in situ pull test. (Abstract shortened by UMI.)...