A novel method for automated trace discontinuity mapping at the Kemano hydroelectric tunnels in Western Canada

Abstract

Mapping of geological structures, as well the subsequent generation of as-built drawings of mine and infrastructure tunnels, is a crucial step in the evaluation of excavation performance during and after construction. Mapping is typically a tedious paper-based process, which is occasionally done with the support of rugged tablets. In either case, geotechnical data is collected manually and then transcribed to a compatible format based on the software that is being used for post-processing or visualization. These traditional data collection practices offer limited quality control, decreased accuracy, and minimal standardization across geotechnical personnel. This paper presents an extension of a geotechnical mapping application, 3-Dimensial Axis Mapping (3DAM), for trace mapping using the RockMass Mapper to the drill and blast and TBM tunnels at the Kemano hydroelectric facility near Kitimat, Canada.The aim of this study is to use the Mapper to capture trace discontinuities in TBM and blasted tunnels, and to integrate the data into industry-standard CAD software that is already used by construction teams to generate drawings. This new application of the 3DAM method will assist in obtaining more accurate geotechnical data in a digital form, allowing for quicker data analysis and more reliable excavation design in the long term.