Abstract:
After completion of slurry control grouting in karst terrain at TVA’ s Boone Dam an
additional two-line high mobility grout curtain targeting the rock at and below the base of
the planned cutoff wall was performed for the purpose of confirming cutoff wall design
assumptions and to provide primary treatment of the rock free of significant karst features
or erodible material below the cutoff wall. The Additional Drilling and Grouting Program
(ADGP) was performed using instrumented packers for all injections during pressure
testing and grouting. This paper summarizes observations of the benefits and challenges
encountered while using instrumented packers from the perspective of an asset owner,
engineer, and contractor with respect to: maintaining safe injection pressures, interpretation
of grouting results, calibration and deployment in construction, and recommendations for
additional research and development to further advance the state of the practice.