GB/T 28900-2022Test methods of steel for reinforcement of concrete (English PDF)

Foreword

This document was drafted in accordance with the rules given in GB/T 1.1-2020,

Directives for standardization - Part 1.Rules for the structure and drafting of

standardizing documents.

This document replaces GB/T 28900-2012 Test methods of steel for reinforcement of

concrete. Compared with GB/T 28900-2012, except for structural adjustment and

editorial changes, the main technical changes are as follows.

-- Change the scope of the document (see Chapter 1; Chapter 1 of the 2012 edition);

-- Add symbols and descriptions of L'o, L'u and deltal; remove the symbol and

description of lambda (see Table 1; Table 1 of the 2012 edition);

-- Change some requirements for the tensile test procedure (see 6.3; 5.3 of the 2012

edition);

-- Add the calculation formula for Ar (see 6.3.4);

-- Add some requirements for the bending test (see 7.3);

-- Add the accuracy requirements for the measurement of width of the transverse rib

(see 11.2);

-- Add the measurement method of height of the transverse rib when there are

different angles (beta) between the transverse rib and the axis (see 11.3.1);

-- Add the schematic diagram M'-M' of the cross-section of two adjacent transverse

ribs along the axial direction (see Figure 6);

-- Remove the empirical formula in the simplified formulae [See Formula (8) of the

2012 edition];

-- Add the sampling position of the test piece used for the determination of weight

deviation (see 13.1);

-- Remove part of the test procedures for the determination of weight deviation (see

2012 edition).

This document is modified and adopted from ISO 15630-1.2019 Steel for the

reinforcement and prestressing of concrete - Test methods - Part 1.Reinforcing bars,

rods and wire.

Compared with ISO 15630-1.2019, this document has a lot of adjustments in structure.

See Appendix A for a list of structure number changes between the two documents.

Compared with ISO 15630-1.2019, this document has many technical differences, and

the terms involved are marked with a vertical single line (|) on the outer margin. See

Appendix B for a list of these technical differences and their reasons.

The following editorial changes have been made for this document.

-- Change the standard name to "Test methods of steel for reinforcement of concrete",

in order to coordinate with the existing standards;

-- Remove Appendix A of ISO 15630-1.2019;

-- Remove Bibliography of ISO 15630-1.2019.

Please note that some contents of this document may involve patents. The issuing

organization of this document is not responsible for identifying patents.

This document was proposed by China Iron and Steel Industry Association.

This document shall be under the jurisdiction of National Technical Committee 183 on

Iron and Steel of Standardization Administration of China (SAC/TC 183).

Drafting organizations of this document. Shougang Group Co., Ltd., China

Metallurgical Information and Standardization Institute, China Metallurgical

Construction Research Institute Co., Ltd., Shaanxi Longmen Iron & Steel Co., Ltd.,

Wuhai Baogang Wanteng Iron and Steel Co. Ltd., Shiheng Special Steel Group Co.,

Ltd., Lianyungang Xingxin Iron and Steel Co., Ltd., Ningxia Jianlong Longxiang Iron

and Steel Co., Ltd., National Steel and Products Quality Inspection and Testing Center,

Zhejiang Institute of Standardization, Lingyuan Iron & Steel Co., Ltd.

Chief drafting staffs of this document. Wu Chaohui, Wang Yujie, Qiu Yu, Zhu Jianguo,

Xi Xiaofeng, Liu Baoshi, Pan Xue, Wang Changsheng, Zheng Guizeng, Wang Shifeng,

Lu Feng, Huang Fei, Chen Liangfu, Shi Li, Li Junrong, Wang Shuo, Xiao Lijun, Zhang

Zexing, Jiang Jianping, Tan Changjiang, Gan Zhengbin, Yu Ziying, Zhao Xiqing, Ma

Xin, Yang Sen.

This document was first published in 2012, and this is the first revision.

Test methods of steel for reinforcement of concrete

1 Scope

This document specifies the test methods of tensile test, bending test, rebending test,

axial force fatigue test, chemical analysis, geometric dimension measurement,

determination of specific projected rib area, determination of weight deviation and

cyclic inelastic load test of steel for reinforcement of concrete.

2 Normative references

The following documents are normatively referenced in this document and are

indispensable for its application. For dated references, only the version corresponding

to that date is applicable to this document; for undated references, the latest version

(including all amendments) is applicable to this document.

GB/T 228.1, Metallic materials - Tensile testing - Part 1.Method of test at room

temperature (GB/T 228.1-2021, ISO 6892-1.2019, MOD)

3 Terms and definitions

Terms and definitions determined by GB/T 38937 are applicable to this document.

4 Symbols and descriptions

The following symbols and descriptions (see Table 1) apply to this document.

5 General provisions concerning the test piece

When determining the performance indicators in the tensile test at room temperature,

bending test, rebending test, axial force fatigue test and cyclic inelastic load test, the

straightened test piece can be artificially aged according to the requirements of the

product standard.

6 Tensile test

The testing machine shall be checked and calibrated according to GB/T 16825.1, and

its accuracy shall reach at least grade 1.

7 Bending test

For a bending test at low temperatures, if the test conditions are not specified in the

agreement, a temperature deviation of +/-2 °C shall be used.

The results of the bending test shall be evaluated in accordance with the provisions of

the relevant product standards.

8 Rebending test

The rebending can be performed on the rebending device shown in Figure 3, or on the

bending device shown in Figure 2.

Bending shall be carried out at a temperature of 10 °C ~ 35 °C, and the test piece shall

be bent on the bending indenter.

The results of the rebending test shall be judged in accordance with the provisions of

the relevant product standards.

9 Axial force fatigue test

The test piece shall comply with the provisions of Chapter 5.

The surfaces of parallel lengths between the clamping parts shall not be surface-treated

in any way and shall not contain product identification. The parallel length shall be at

least 140 mm or 14d (whichever is greater).

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