Infrastructure Chemical Grouting
The first Chemical Grout applied to leaking infrastructures occurred in 1955. Since then, it has been used to stop leaks in manholes, tunnels, sewers, lift stations, wet wells, and many other applications all over the world. Recent studies have shown that some of the first repairs completed are still intact and still providing leak protection after 50+ years of service.
NASSCO studies have shown that trenchless Chemical Grouting is still the best, most cost-effective, long-term defense against groundwater infiltration into structurally sound sewer systems. Infiltration occurs when defects in below-grade structures like sanitary sewer lines, manholes, pump stations, catch basins or storm drains allows groundwater to enter the system. This infiltration multiplies treatment costs and increases the flows in sanitary sewer systems and cause sewer system overflows (SSO’s). Groundwater also carries silt, sand and other debris into the system, increasing the wear-and-tear on equipment and accelerating the need for cleaning and de-silting. Voids are often created around these structures and can lead to settlement, unstable foundations and roadbed failures.
Leaks in manholes are typically repaired by applying quick-set cement over the active leak while a lining system is installed. This repair is easily damaged due to failure of such patches, allowing groundwater to remain in the primary structure and cause weak bonds or future failure of the lining system.
Our process of sealing begins with injecting a 2-part polyurethane under high pressure to the outside of the structure to penetrate the voids and leaks from the outside, in! This allows for little or no chance of failure as this product will last indefinitely unless exposed to direct sunlight (for years). And best of all, the back-pressure of the leak acts to pull the chemical grout into the structure. This product flows as a liquid to find all leaks and cracks and permanently seals these as it expands 20+ times its volume as a liquid. This not only stops the leaking and seals the structure; it compacts the weak soils and fills voids found outside the structure to help support surface soils and road beds, and it will not over-burden the surrounding soils.