This standard specifies terms, definitions and symbols, product classification, code and mark, general requirements, requirements, test methods, inspection rules, marking, packaging, transportation and storage of anchorage, grip and coupler for prestressing tendons.
This standard is applicable to anchorage, grip and coupler in bonded, unbonded or retard-bonded prestressing structure of internally and externally prestressing tendons and those used during special construction, anchorage and coupler for cable.
2 Normative References
The following documents are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 197 General Purpose Metric Screw Threads-Tolerances
GB/T 230.1 Metallic Materials - Rockwell Rigidity Test - Part 1: Test Method (Scales A, B, C, D, E, F, G, H, K, N, T)
GB/T 231.1 Metallic Materials - Brinell Rigidity Test - Part 1: Test Method
GB/T 1348 Spheroidal Graphite Iron Castings
GB/T 1804 General tolerances - Tolerances for Linear and Angular Dimensions without Individual Tolerance Indications
GB/T 5223 Steel Wires for the Prestressing of Concrete
GB/T 5223.3 Steel Bars Prestressed Concrete
GB/T 5224 Steel Strand for Prestressed Concrete
GB/T 9439 Grey Iron Castings
GB/T 9969 General Principles for Preparation of Instructions for Use of Industrial Products
GB/T 12361 General Specification of Steel Die Forgings
GB/T 15822.1 Non-destructive Testing - Magnetic Particle Testing C Part 1: General Principles
GB/T 16825.1 Verification of Static Uniaxial Testing Machines - Part 1: Tension/Compression Testing Machines - Verification and Calibration of the Force-Measuring System
GB/T 16923 Normalizing and Annealing of Steel Parts
GB/T 16924 Quenching and Tempering of Steel Parts
GB/T 20065 Screw-thread Steel Bars for the Prestressing of Concrete
GB/T 21839 Steel for Prestressed Concrete - Test Methods
GB/T 26743 Fiber Reinforced Composite Bars for Civil Engineering
JB/T 5000.8 Heavy Mechanical General Techniques and Standards-Part 8: Forging
JB/T 5000.9 Heavy Mechanical General Techniques and Standards-Part 9: Cutting
JB/T 5000.10 Heavy Mechanical General Techniques and Standards - Part 10: Assembly
JB/T 5000.13 Heavy Mechanical General Techniques and Standards - Part 13: Packing
JB/T 5000.15 Heavy Mechanical General Techniques and Standards - Part 15: Non-destructive Inspection of Forged Steel
JG/T 330 Cables for Construction Engineering
JG/T 351 Fiber-reinforced Composite Bars
3 Terms, Definitions and Symbols
For the purpose of this standard, the following terms, definitions and symbols apply.
3.1 Terms and definitions
3.1.1
anchorage
a permanent anchorage device used for keeping tension of prestressing tendons and transmitting it to the structure
3.1.2
grip
a temporary anchorage device (also known as tool anchor) for generating or keeping prestress of prestressing tendons
3.1.3
coupler
a device for connecting prestressing tendons
3.1.4
prestressing tendon
tensile element such as single or bunchy prestressing steel or fiber-reinforced composite bars for generating prestress
3.1.5
prestressing steel
a general term of steel wire, steel bar, steel strand, steel wire rope, spiral reinforcement and steel tie rod for prestressed structure
3.1.6
fiber-reinforced composite bars
rod-shaped fiber reinforced polymer product made of continuous fiber bundle by pultrusion process
3.1.7
prestressing tendon-anchorage assembly
tension unit assembled from prestressing tendon and anchorage installed at its ends
3.1.8
prestressing tendon-grip assembly
tension unit assembled from prestressing tendon and grip installed at its ends
3.1.9
prestressing tendon-coupler assembly
tension unit assembled from prestressing tendon and coupler installed at its ends
3.1.10
cable
members in tension in engineering structure composed of parts such as cable body and anchorage
3.1.11
tension length
clear distance between anchorage and grip at both ends of prestressing tendon or between anchorage and coupler
3.1.12
anchorage zone
local zone where the prestress is transmitted to concrete structure by anchorage and bearing plate
3.1.13
bearing plate
anchorage component bearing prestress and transmitting it to structure in post-stretching prestressed concrete
3.1.14
spiral reinforcement
anchorage component in prestressed concrete structure used in conjunction with bearing plate in the anchorage zone in order to improve concrete crack resistance and ultimate bearing capacity of the anchorage zone
3.1.15
draw-in
rebound phenomenon of prestressing tendon generated by relative displacement and local plastic deformation between anchorage parts or between anchorage and prestressing tendon in the process of anchorage
3.1.16
prestress loss due to friction at anchorage device
prestress loss due to friction at the corner of bearing plate on the anchorage and stretching end
3.2 Symbols
For the purpose of this document, the following symbols apply.
Apk——the nominal cross-sectional area of prestressing tendon, mm2;
Fpm——the measured average ultimate tension resistance of single piece of prestressing tendon, kN;
Fptk——the nominal ultimate tension resistance of prestressing tendon, kN;
FTu——the measured ultimate tension resistance of prestressing tendon - anchorage, grip or coupler assembly, kN;
Fu——the measured failure load of force transmission property test in anchorage zone, kN;
fck,o——the characteristic compression strength which concrete members shall reach when it is allowed to apply all the prestress, MPa;
fcm,e——the measured average compression strength of concrete cubic specimen cured under the same condition during force transmission property test in anchorage zone, MPa;
fcm,o——the average compression strength which concrete cubic specimen cured under the same condition shall reach when it is allowed to apply all the prestress, MPa;
fptk——the nominal tensile strength of prestressing tendon, MPa;
n——the number of prestressing tendon in prestressing tendon - anchorage or coupler assembly;
εTu——the total strain of prestressing tendon tension length when prestressing tendon - anchorage or coupler assembly reaches the measured ultimate tension resistance FTu, %;
ηa——the anchorage efficiency factor measured in static load anchoring property test of prestressing tendon-anchorage assembly, %;
ηg——the grip efficiency factor measured in static load anchoring property test of prestressing tendon-grip assembly, %.
4 Product Classification, Code and Mark
4.1 Product classification
According to anchorage mode of prestressing tendon, anchorage, grip and coupler may be classified into wedge-type, bearing-type, bond-type and combined type.
4.2 Code
Codes of anchorage, grip and coupler are shown in Table 1.
