An anchoring device including an anchoring element suitable for being anchored an object of construction material with the aid of mechanical vibrations. The anchoring element includes a thermoplastic material and a tool. The thermoplastic material forms at least a part of a radially outer surface of the anchoring element, and the tool has a proximal portion and a broadening portion distally of the proximal portion. The broadening portion has an outer second cross-section, the second cross section being larger than the first cross section but being adapted to the first cross section so that the tool can be moved with respect to the anchoring element while the broadening portion is in the axially-extending opening and locally expands the anchoring element while thermoplastic material of the anchoring element that surrounds the broadening portion is in a solid state.