Information and knowledge behind data from underground rock grouting

Abstract

Data related to the pre-grouting work of a large underground project are systematically analyzed to reveal the mechanism behind, to shed some light on the execution of practical grouting, and to enrich the theory of engineering geology. Grouting is generally taken as an effective way for controlling non-ignorable water seepage during underground rock excavation. Though various models have been developed to guide grouting design or to specify criteria for grouting stop, it does not change the fact that grouting is still highly experience-based. Therefore, explanation of the current situation due to grouting complexity is given through step-by-step data analysis, where the impact on grouting parameters from the geological and hydrogeological conditions is investigated, and the grouting features of two tunnels located at the same depth below the sea surface are compared and discussed. Then, the data from individual grout hole are used to construct the regional geological conditions via inverse analysis. It is found that grouting of fractured rock masses is accompanied with great uncertainty, and field grouting data can contribute significantly to a better understanding of the regional geological conditions around an underground tunnel or rock cavern.

Keywords

• Field grouting data
• Water seepage
• Rock grouting
• Inverse modelling
• Data analytics
• Geological conditions