Contact Grouting Services
Contact grouting involves the filling of void space between a cast-in-place (CIP) structure and the in-situ geo-material. Generally, the intent of contact grouting is to increase the structural integrity of the CIP structure. Contact grouting is typically done in association with CIP liners for tunnels, shafts, mine plugs, etc. Contact grouting may be necessary for numerous reasons, but the primary function is to ensure intimate contact between the CIP structure and the in-situ material.
Examples of where contact grouting may be used include the following:
- Within pressure tunnels to prevent expansion of the tunnel liner under pressure
- Around mine plugs to ensure contact of the entire plug with the surrounding rock
- To ensure a minimum thickness of liner is achieved in any cast in place liner system
- Within sewer tunnels to prevent sulfate attack of concrete liners from behind the liner
- Within non-pressure tunnels where exfiltration of tunnel contents are a concern
The term contact grouting does not define the type of grout used. Many contact grouting programs are accomplished using ordinary Portland cement grouts; however, based on the void characteristics and the intent of the grouting program, microfine cements or chemical grouts may be utilized.