Patent ID: 8066452

Claim:
A method for the construction of active anchors in soil, said method comprises the following stages: drilling with a rotating drilling rod fitted at the head with a bit comprising at least one nozzle adapted to inject a high-pressure liquid in front of the bit until the stable soil strata are reached, said drilling rod being comprised of a number of elements and, while rotating, driving the rotation of said bit; injecting a high-pressure grout, when the rotating bit reaches and begins to drill the stable soil strata and while it continues to drill such stable soil strata, so as to form a concrete pile that surrounds the drilling rod in the stable soil strata, wherein said high-pressure grout is injected through one or more lateral nozzles provided on said bit; pulling a protective tube that does not adhere to the drilling rod during said drilling, said protective tube being inserted as far as the area where the rotating bit reaches the stable soil strata and thereby the grout injection begins; anchoring the proximal end of the drilling rod to a plate, when the required depth has been reached; applying a traction to the drilling rod if necessary, when the grout has been consolidated; and finally injecting grout into said protective tube.