Bituminous grouting is also known as asphalt grouting. This grouting technique involves the injection of an asphalt material (similar to roofing tar). The method is almost exclusively used for stopping large inflows (generally greater than 1,000 gpm), although may be used in applications where its elasticity in the cured state is desirable. Bituminous grouting is generally used where void size or water flow is too great to allow other grouting methods to work due to grout washout. The advantage of bituminous grout is that as the hot bitumen is pumped into the ground, eventually, a leading edge of cured, elastic bitumen forms. Additionally grout fills the cured leading edge and expands the grout mass, similar to inflating a balloon. The leading edge forms a protective layer, keeping additional grout from being washed out. Eventually, the mass will grow large enough to either fill the void space available at the injection point, creating a seal within the void.
Bituminous grouting applications are most often associated with mining operations such as quarries or with dams which are experiencing large volumes of seepage. Goettle has the capability to design and place bituminous grouts based on the project requirements.