Grouting Works
ROCK GROUTING
Rock grouting is generally used to seal rock masses, for the construction of dams and other underground structures like tunnels and caverns, or for the filling of large cavities, such as the karsts. The injection of liquid suspension into rock happens directly from the unsupported borehole by using mechanical or hydraulic packers. Goal of rock grouting is the filling of existing cracks or voids in the rock. For rock grouting usually stable cement suspensions based on normal or ultra-fine cements are used. In recent times, the so-called GIN method has proved to be a very efficient system for rock grouting. Control of the results of the injection is based on core drilling and water pressure tests (Lugeon tests).
COMPENSATION GROUTING
Compensation grouting is a very specific application of the injection field. By means of Compensation grouting it is possible to compensate settlement caused by tunnel excavation. In case of excavation under buildings at shallow overburden, settlement and rotations caused by excavation might be dangerous for the structures when not compensated. Grouting occurs through steel sleeved pipes who are installed
on horizontal holes made starting from shaft. By this way, a net of grouting points is created between the foundations and the tunnel. Grouting of every point can
be precisely controlled in order to compensate settlement with the injection of cement grouts. Building movements are continuously controlled by means of a net of measuring points (electro levels). A specially conceived software permits to link grouted volumes with settlements and heaves within each single zone and allows a precise control of the complex grouting process.
