Grout Injected Piers
What are Grout Injected Piers and how are they installed?
Grout Injected Piers are a hybrid sinkhole repair method which combines the support strength of Steel Piers and the sinkhole filling capabilities of Compaction Grouting. In essence, the sinkhole activity is remediated by the action of the grout targeting and sealing the top of the limestone layer while the installed steel piers provide direct structural stabilization. Grout injection piers can be installed at an outstanding value when compared to doing both compaction grouting and underpinning combined.
The process begins much the same as regular steel piers with the exception of the first few pipe sections of the steel pier are not solid, they are perforated with 1″ holes. The repair begins by reviewing the Geotechnical Engineer’s repair design and installation points are located around the property. These installation points are hand excavated and the footer of your structure chipped back flush to the foundation wall. Champion’s ULTrA bracket is set in place and squared to the bottom of the foundation. Champion’s dual hydraulic drive assembly is connected to the ULTrA bracket and lead pipe section and subsequent pipe sections are hydraulically driven deeper and deeper to the limestone layers. Driving is terminated when the pier stops it’s advance downward and the structure starts to lift upward. Champion’s lifting assembly is then connected to the top of the steel pier and the structure lifted back into its original state.
The inside of the grout injected pier is flushed with water to clear out any soil which might have entered the pier. Grout is then pumped through the pier down to the limestone layer to seal the top of the rock to stop the raveling and solidify the base of the pier in concrete. The dirt is removed from the tarps and placed back in the excavation hole and compacted. At this time new sod is laid over the installation points and fresh landscaping restores the yard.
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