High Strength Reinforcing System (HSR)
High Strength Reinforcing System (HSR) utilizes fully threaded bars of 670 / 800 N/mm² (Grade 97) due to high yield, ultimate and bond strength as compared to normal reinforcement bar grades of 60 and 75.
Threaded Bars 670/800 are available in diameters of 18 to75 mm and can be used in buildings as HSR covering the following applications.
- Ductility class B according to EN 1992-1-1 (EC 2)
- Columns and walls stressed to compression
- Structural members with high reinforcement ratio (e.g. frame corners)
- Compressive reinforcement for all structural members
- Dual reinforcement (used as typical reinforcement for normal load cases, used as high strength reinforcement for accidental load cases)
- Longitudinal reinforcement
Design
While the rules for design of columns are governed by the corresponding national standard, the design specifications for HSR 670/800 are given in the European Technical Assessment held by our system partner. With reference to Eurocode 2 there are some deviations for high performance compression members.
- Increase of the permitted concentric concrete strain to fully utilize the yield strain of the reinforcement by considering effects due to creep and shrinkage
- Increase of maximum reinforcement ratio up to 20%
- Reduction of the minimum diameter for stirrups from 1/4 to 1/6 of the diameter of the main reinforcement for large diameters
- Minimum distance between couplers ≥ 30 mm
Accessories
We provide a wide range of accessories such as nuts, couplers, end anchorages and special parts. Lap splices can be avoided by using couplers. Development length can be reduced by using end anchorages.
Advantages
- About 25% less reinforcement (25% saving of reinforcement weight) for the same bearing capacity compared to normal reinforcement
- Lower costs for material and labour
- Simple configuration of reinforcement
- High strength concrete with typical reinforcement can be substituted by normal strength concrete and HSR