Anchorage is a permanent anchorage device used in prestressed concrete. 

Anchorage is a permanent anchorage device used in prestressed concrete. It is an anchorage tool used in post-tensioning structure or member to maintain the tension of prestressed reinforcement and transfer it to the concrete interior. It is also called pre-stressed anchorage.

A permanent anchorage device for concrete.Anchors can be divided into two categories: (a) Tensioned end anchors: anchors that are installed at the end of prestressed reinforcement and can be tensioned, are also called prestressed anchors. The so-called anchors are anchors in post-tensioned structures or members that maintain the tension of the prestressed reinforcement and transfer it to the concrete; (b) Fixed end anchorage: anchorage installed at the end of prestressed reinforcement, usually embedded in concrete and not tensioned.The standard of anchorage for prestressed reinforcement is: the National standard of the People's Republic of China (GB/T 14370-2007)

Common specification  

At present, the anchorage specifications commonly used in China are: (a) M15-N anchorage. M stands for anchorage (the first letter of Chinese pinyin for anchorage); 15 represents the steel strand with a specification of 15.24mm (China's generally used steel strand strength of 1860MPa class 15.24mm); -N is the number of strands to be threaded. (b) M13-N anchorage. M stands for anchorage (the first letter of Chinese pinyin for anchorage); 13 Represents the 12.78mm steel strand (the 12.78mm steel strand strength of 1860MPa that is commonly used in foreign countries); -N is the number of strands to be threaded.

Prestressed anchor products include: group anchor, P anchor, connector, ring anchor, Frasier anchor and other specifications. And each specification is divided into 15 series and 13 series. Anchors of 15 series are widely used nowadays.Common system classification

(1) Round cylinder anchorage. The specifications and models are: YM15-N or YM13-N(Y, the first letter of pinyin for round anchor, which means round anchor); The anchoring tool has good anchoring performance and self-anchoring performance. In general, through-center jacks are used.

(2) Rectangular flat anchorage. The specifications and models are: BM15-N or BM13-N (B, the first letter of pinyin for flat anchor, which means flat anchor); The flat anchor is mainly used for transverse prestressed bridge deck, hollow slab and low-height box girder to make the stress distribution more even and reasonable and further reduce the thickness of the structure.

(3) Holding and wrapping anchorage. (Fixed end anchor) Specification and model: AM15P-N or AM13P-N; It is applicable to the case where the design stress of the end cloth is large or the end space is limited. It uses an extruder to compress the squeeze sleeve on the steel strand. It is embedded in the concrete and arranged as required.

 Application