Multiple part tapered collar for a tendon anchorage system

Claim 1

Multiple part tapered collar for use as a component of a wedge anchorage system for a tendon in a structural concrete unit, comprising a plurality of axially extending parts combining to form an axially extending annular collar said parts of said collar having an inner surface and an outer surface with the inner surrace arranged to bear against the tendon in the form of a wire, rod or the like and with the outer surface arranged to bear against the surface of a frusto-conically shaped bore in an anchoring member, wherein the improvement comprises that each of said parts have a first end and a second end with the outer surface thereof tapering inwardly from the first end to the second end, said parts combining to form longitudinal grooves extending in the axial direction of said collar for the axial length thereof between the first ends and second ends of said parts for forming a passage for the injection of neat cement or similar material around the tendon, said longitudinal grooves being formed in the outer surfaces of said parts of said collar and having a uniform depth for at least a major portion of the axial length thereof, each said part has a pair of axially extending edges in the assembled collar with a recess along the radially outer end of each said edge with the recess extending radially inwardly along the edge to a position intermediate the inner and outer ends of the edges, the recesses in adjoining edges of said parts forming said grooves.