Sireg Obturator Bags MPSP, made in polypropylene geotextile, are used to seal the space between the Durvinil® TAM pipe and the borehole, when required in order to execute grouting treatments in fractured or permeable soils, when the cement/bentonite sheath can’t be executed.
The product is characterized by the heavy duty seams which confer extreme resistance during the filling.
The obturator bags to perform correctly the MPSP (Multiple Packer Sleeved Pipe) technique. They are also used in the situations in which the stability of the walls of the hole is compromised.
Obturator Bag TNT450-Sireg geotextile barrel bag is also used where the cement and bentonite sheath cannot be made correctly or when the injection column crosses soils with heterogeneous properties.
The cement inflation of the product is easy and it seals immediately, for this reason it is used in perforations from the bottom upwards (for example in the tunnel vault).
The procedure for using geotextile shutter bags with valved pipes involves the following steps:
- Hole drilling with the most suitable drilling techniques;
- Insertion of the TAM pipe with mounted bags. Some injection valve are placed between 2 consecutive obturator bags.
- Placing of a double packer near the valve/manchette dedicated to inflate the bag;
- Filling of the bags with the portland cement mix. The bag, swelling with cement, it seals the annular space between the tube and the walls of the hole;
- Now it is possible to inject through the remaining free valves between two bags.
The TAM pipe used with the Obturator bags are reinforced type.
The shaped geotextile obturator bags are supplied with steel clamps if necessary.
The special tubular obturator bags are also used for the correct cementation of steel micropiles and tie rods to contain the cement near the bulb.
In this situation, the bags works as a “sock” around the micropile, preventing the dispersion of cement in the ground.
Combined with particular accessories, they allow injection under pressure, further increasing the adhesion of the anchorage of the tie rod.
The obturator bags coupled with the RFS drainage pipes allow to capture the water only in defined sections along the draining axes.
In this case, the product is sold with a dedicated injection nozzle.