Tendon for post-tensioning prestressed concrete and process for making the tendon

摘要

A tendon for use in posttensioning prestressed concrete comprising a multi-wire strand (12) wherein individual peripherally abutting wires (16) define both internal (20) and external (18) interstices between themselves and a central wire (14), the external interstices (18) being substantially fully filled with a dielectric plastics material such as a high molecular polyolefinic material e.g. high density polyethylene. The plastics material forms an encasement (22) completely surrounding the strand and providing it with a smooth outer surface of circular cross-section. A friction-reducing, grease-like material (28) is coated on the encasement and the entire structure is thereafter enclosed in a plastics jacket (32). The above structure is formed by progressively extrusion coating the wire strand with the dielectric plastic, coating the strand with the grease-like material and subsequently applying to the thus coated composite with a plastics material to form the jacket.