GB 13014-2013Quenching and self-tempering ribbed bars for the reinforcement of concrete (English PDF)

6.1 Nominal diameter range and recommended diameter

Reinforced nominal diameter in the range of 8mm ~ 50mm, RRB400, RRB500 recommended reinforced nominal diameter of 8mm, 10mm, 12mm, 16mm, 20mm, 25mm, 32mm, 40mm, 50mm, RRB400W reinforced preferred diameter of 8mm, 10mm, 12mm, 16mm, 20mm, 25mm, 32mm, 40mm.

6.2 Nominal cross-sectional area of the theoretical weight

Reinforced nominal cross-sectional area and the theoretical weight set forth in Table 2.

Table 2

Nominal diameter/mm nominal cross-sectional area/mm2 theoretical weight/(kg/m) twenty two 50.27 78.54 113.1 153.9 201.1 254.5 314.2 380.1 490.9 615.8 804.2 0.395 0.617 0.888 1.21 1.58 2.00 2.47 2.98 3.85 4.83 6.31 7.99 9.87 15.42

NOTE. theoretical weight calculated density of 7.85g/cm3.

Surface shape and dimensions 6.3 ribbed steel tolerance 6.3.1 ribbed steel horizontal rib design principles should meet the following requirements.

a) the angle beta axis transverse ribs and steel of not less than 45 °, when the angle is not more than 70 °, reinforced transverse ribs on opposite sides of a direction should in contrast.

b) transverse ribs nominal spacing not greater than 0.7 times the nominal rebar diameter.

c) the cross ribs and reinforced side surface angle alpha of not less than 45 °.

d) steel cross ribs on opposite sides of the gap between the ends (including longitudinal ribs width) shall not exceed the sum of the nominal 20% reinforced perimeter.

e) When the bar nominal diameter of not more than 12mm, the relative rib area of not less than 0.055; nominal diameter of 14mm and 16mm , The relative rib area of not less than 0.060; nominal diameter greater than 16mm, the relative rib area of not less than 0.065. relatively Calculation rib area refer to GB 1499.2-2007 Appendix C.

6.3.2 ribbed steel usually with longitudinal ribs, or without longitudinal ribs.

6.3.3 with longitudinal ribs crescent ribbed steel bars, its shape shown in Figure 1, the dimensions and tolerances shall comply with the provisions in Table 3. Weight deviation breaks Together Table 4, the inner diameter deviation not reinforced delivery conditions.

6.3.4 without longitudinal ribs crescent ribbed steel bars, its diameter size can be specified in Table 3 to make appropriate adjustments, but the weight tolerance should still be in accordance with Table 4 stipulations.

Explanation.

d1 --- reinforced inner diameter;

alpha --- oblique transverse ribs;

h --- transverse rib height;

beta --- cross ribs and the axis angle;

h1 --- longitudinal rib height;

theta --- oblique longitudinal ribs;

a --- longitudinal rib top width;

l --- lateral rib spacing;

b --- horizontal rib top width.

Figure 1 crescent steel (with longitudinal ribs) and cross-sectional shape of the surface

Table 3 millimeters

Nominal

diameter

The inner diameter d1 transverse rib height h Nominal size Nominal size Tolerance Tolerance Longitudinal rib height h1 (no greater than) Transverse ribs Top width b Longitudinal ribs A top width Spacing l Nominal size Tolerance the end of the maximum transverse ribs Gap (nominal perimeter 10% of the chord) 8 7.7 10 9.6 11.5 12 13.4 14 15.4 16 18 17.3 19.3 20 22 21.3 24.2 25 28 27.2 31.0 32 35.0 36 38.7 40 48.5 50 ± 0.4 ± 0.5 ± 0.6 ± 0.7 ± 0.8 0.8 1.0 1.2 1.4 1.5 1.6 1.7 1.9 2.1 2.2 2.4 2.6 2.9 3.2 0.4-0.3 ± 0.4 0.4-0.5 ± 0.5 ± 0.6 0.8-0.7 1.0-0.8 ± 1.1 ± 1.2 1.1 0.5 1.5 5.5 1.3 0.6 1.5 7.0 1.6 0.7 1.5 8.0 1.8 0.8 1.8 9.0 1.9 0.9 1.8 10.0 2.0 1.0 2.0 10.0 2.1 1.2 2.0 10.0 2.4 1.3 2.5 10.5 2.6 1.5 2.5 12.5 2.7 1.7 3.0 12.5 3.0 1.9 3.0 14.0 3.2 2.1 3.5 15.0 3.5 2.2 3.5 15.0 3.8 2.5 4.0 16.0 ± 0.5 ± 0.8 ± 1.0 2.5 3.1 3.7 4.3 5.0 5.6 6.2 6.8 7.7 8.6 9.9 11.1 12.4 15.5

Note 1. longitudinal rib angle theta of 0 ° ~ 30 °.

Note 2. Dimensions a, b of the reference data.

6.4 Length and tolerance

6.4.1 Length

6.4.1.1 steel is usually delivered by length, specific length of delivery should be specified in the contract.

6.4.1.2 Reinforced can coil delivery, each dish should be a reinforced, allowing each batch of 5% Number of Discs (can have two time less than two) consists of two Strip steel components. Its plate weight and diameter is determined by the supply and demand sides negotiated.

6.4.2 Length tolerance

Reinforced by the length of time of delivery allows deviation 0 ~ 50mm.

6.5 Bending and ends

Straight bars bending degree should not affect normal use, the total curvature of not more than 0.4% total length of steel.

Reinforced cut ends should be honest, should not affect the use of local deformation.

6.6 Weight and tolerances

6.6.1 reinforcement according to the actual weight or theoretical weight delivery.

6.6.2 Reinforced actual weight and theoretical weight tolerances shall comply with the requirements of Table 4.

Table 4

Nominal diameter/mm theoretical weight and the actual weight deviation /% 8 ~ 12 ± 6 14 ~ 20 ± 5 22 ~ 50 ± 4

7.1 Grades and chemical composition

7.1.1 Steel grades, chemical composition and carbon equivalents (melting analysis) should meet the requirements of Table 5. If necessary, the steel may be added V, Nb, Ti and other elements.

table 5

Trademark

Chemical composition (mass fraction) /% (not more than) C Si Mn PS Ceq RRB400 RRB500 0.30 1.00 1.60 0.045 0.045 -RRB400W 0.25 0.80 1.60 0.045 0.045 0.50 7.1.2 carbon equivalent CEV (percentage) value according to equation (1).

CEV = C Mn/6 (Cr V Mo)/5 (Cu Ni)/15 (1) 7.1.3 residual content of chromium steel, nickel, copper should each not more than 0.30%, a total amount of not more than 0.60%. By the need to agree, copper-containing residue the amount may not be greater than 0.35%.

7.1.4 steel nitrogen content should not exceed 0.012%. As the supplier can guarantee may be analyzed. If a sufficient number of steel nitrogen binding elements, Nitrogen content restrictions may be relaxed.

Finished chemical composition 7.1.5 reinforcement tolerances shall comply with the provisions of GB/T 222's. Carbon equivalent CEV to allow deviation 0.02%.

7.2 Delivery Status

Reinforced with heat treatment delivery.

7.3 Mechanical Properties

7.3.1 mechanical testing conditions for the delivery status or artificial aging state. In case of dispute, the test conditions were by artificial aging.

Mechanical performance characteristics 7.3.2 reinforcement value should be in accordance with Table 6.

Table 6

Trademark

ReL/MPa Rm/MPa A /% Agt /% not less than RRB400 400 540 14 RRB500 500 630 13 5.0 RRB400W 430 570 16 7.5

NOTE. After the aging test results.

7.3.3 diameter 28mm ~ 40mm various grades of steel Elongation A can be reduced by 1%. Diameter greater than 40mm of various grades of steel the percentage elongation rate can be reduced by 2%.

7.3.4 For no apparent yield strength steel, the yield strength characteristic values ReL should be non-proportional extension strength Rp0.2.

7.3.5 According to the agreement between the elongation of the type can be selected from the A or Agt. Such as the type of elongation without the agreement determination, the elongation Using A. Using Agt arbitration test.

7.4 Process Performance

7.4.1 Bending performance

Table 7 provides the core diameter bend after bend 180 °, reinforced by the curved parts of the surface can not crack.

Table 7 millimeters

Grade nominal diameter core diameter d bend RRB400 RRB400W 8 ~ 25 4d 28 ~ 40 5d RRB500 8 ~ 25 6d

7.4.2 Reverse bending performance

7.4.2.1 According to the requirements, it can be reinforced reverse bending performance test.

7.4.2.2 Reverse bending test bending test bending core diameter than the corresponding increase in a bar diameter.

7.4.2.3 Reverse bending test. first forward and then backward bend 90 ° bend 20 °. After the reverse bending test, reinforced by the curved parts of the surface can not crack.

7.5 Fatigue Performance

To request, by agreement between, the fatigue performance test. Technical requirements and test methods for fatigue testing by both parties OK consultations.

7.6 Connectivity

Quality inspection and acceptance of welded steel and mechanical connections shall comply with the relevant standards.

7.7 Surface quality

7.7.1 The reinforcement should be no harmful surface defects.

7.7.2 The weight of the sample is too long by wire brush, size, tensile properties and cross-sectional area not less than the requirements of this standard, descaling, surface Iron or uneven skin is not cause for rejection.

7.7.3 When the sample surface defects with a defect 7.7.2 does not comply with the provisions other than the bending tensile properties or performance requirements, it is considered these defects are harmful.

7.8 Features

Heat treated steel with the characteristics given in Appendix A.

8.1 Test Project

Each batch of steel test items, sampling methods and test methods shall comply with the requirements in Table 8.

8.2 connectivity testing, metallurgical testing only type test, that is when steel production technology, there are significant changes and new products get on.

8.3 Stretching, bending and reverse bending test

8.3.1 stretching, bending, reverse bending test specimens does not allow turning.

8.3.2 calculation strength of steel with the cross-sectional area of the use of public listed in Table 2, said cross-sectional area.

Test total elongation Agt 8.3.3 maximum force, in addition to the requirements in Table 8 using GB/T 228.1 Test Method about outside, may also be used GB/T 28900.

8.3.4 reverse bending test, the sample after bending forward, should be at a temperature less than 100 °C insulation 30min, after natural cooling Then reverse bending. When the supplier can guarantee reinforced by reverse bending properties after artificial aging, the sample also positive after bending at room temperature BARS Then reverse bending.

8.3.5 artificial aging conditions. The sample is heated to 100 °C, heat 60min ~ 75min at 100 °C ± 10 °C, and then in the rest Air cooled to room temperature.

Table 8

Test item number of samples Sampling Methods Test Method chemical composition (Melting analysis)

1 GB/T 20066

GB/T 223

GB/T 4336

2 2 optionally stretching two steel cut GB/T 228.1, this standard 8.3 3 2 optionally two curved steel cut GB/T 232, this standard 8.3 4 1 optionally a reverse bend YB/T 5126, this standard 8.3 5 consultation fatigue test 6 connectivity consultations 7 microstructure consultation Size 8 by branch - this standard 8.4

9.1 Characteristic value test

9.1.1 eigenvalue test applies to the following conditions.

a) supply-side inspection of product quality control;

b) demand-side request, by agreement between the same test;

c) third-party product certification and arbitration inspection.

9.1.2 eigenvalue test shall GB 1499.2-2007 Appendix B regulations.

9.2 Delivery Inspection

9.2.1 Scope

Delivery acceptance test is suitable for testing batches of steel.

9.2.2 Batch rules

9.2.2.1 reinforcement should be granted inspection and acceptance, each batch by the same grade, the same furnace number, same size, same heat treatment system Steel components. Batch weight of not more than 60t. Part of more than 60t, 40t each additional (or less than the remainder of 40t), adding a tensile test Test specimens and a bend test specimens.

9.2.2.2 Allow the same grade, the same smelting methods, different furnace number one method of composition pouring mixed batch, but the carbon content of each furnace number the difference is not more than 0.02%, the difference between the amount of manganese is not more than 0.15%. Mixed batch weight is not more than 60t.

9.2.3 Test items and the number of samples

Steel test items and the number of samples shall comply with the provisions of 9.2.2.1 and Table 8.

9.2.4 Test Results

Test results for each test item should be consistent with the relevant provisions of Chapter 6 and Chapter 7.

9.2.5 Reinspection and determination

Reinforced retest determination shall comply with GB/T 17505 of.