GeoBuild provides ground improvement services in order to control settlement and improve the reliability of the subgrade materials. Our design-build team is consistently researching methods and design concepts to more effectively serve our clients and we view ground improvement as a large part of our offerings moving forward.
The history of coal mining in western Pennsylvania and eastern Ohio has left a legacy of abandoned coal mines. Room and pillar mining methods leave voids after most of the coal is removed. These voids can eventually lead to subsidence at the surface.
For linear features, such as roadways, a two-phase grouting program is often employed to mitigate the presence of mine voids. This approach consists of initial low-mobility grouting of the void, followed by another phase of grouting using a high-mobility mix. The result is the substantial backfilling of the voids, thereby protecting from further degradation. GeoBuild has completed numerous deep mine grouting projects across the coal regions of Ohio and Pennsylvania.
Chemical grouting consists of the introduction of chemical compounds, often under pressure, into a substrate to improve its engineering behavior or physical properties. Examples where we have used these tools include polyurethane grouting of shallow voids behind shotcrete, tunnel rehabilitation, and resin grout injection in dam concrete to improve watertightness of concrete joints.
Sinkholes can develop when subsurface erosion/dissolution of limestone/ dolomite occurs. These features are frequently encountered in civil works where these conditions are present. Remediation techniques, such as compaction grouting and other grouting methods, are generally implemented to fill voids and improve bearing capacity or spanning techniques that bypass sinkhole features. We have used specialized drilling techniques to overcome sinkholes when encountered in our projects.