Anchoring method making it possible to break free from the material in which an expansion bolt is to be anchored, device, expansion bolt and drill bit for its implementation

摘要

The invention relates to a method, a device, an expansion bolt and a drill bit. This method includes the formation of a cylindrical preliminary hole 1 and of a conical drilling 4 of small conicity which is less than the conicity of the full expansion of an expansion bolt 3 and of sufficient length L to allow the full expansion of the expansion bolt 3 at the far end of the conical drilling 4. Thus, according to the invention, it is possible to form conical drillings at a great depth and the expansion bolt is anchored in the material by prestressing the latter. <IMAGE>