GB/T 20065-2025 (GB/T 20065-2016) PDF English
US$140.00 · In stock · Download in 9 secondsGB/T 20065-2016: Screw-thread steel bars for the prestressing of concrete Delivery: 9 seconds. True-PDF full-copy in English & invoice will be downloaded + auto-delivered via email. See step-by-step procedureStatus: Valid GB/T 20065: Evolution and historical versions
| Standard ID | Contents [version] | USD | STEP2 | [PDF] delivery | Name of Chinese Standard | Status |
| GB/T 20065-2025 | English | RFQ |
ASK
|
3 days
|
Screw-thread steel bars for the prestressing of concrete
| Valid |
| GB/T 20065-2016 | English | 140 |
Add to Cart
|
0-9 seconds. Auto-delivery
|
Screw-thread steel bars for the prestressing of concrete
| Valid |
| GB/T 20065-2006 | English | 70 |
Add to Cart
|
0-9 seconds. Auto-delivery
|
Screw-thread steel bars for the prestressing of concrete
| Obsolete |
Excerpted PDFs (Download full copy in 9 seconds upon purchase)PDF Preview: GB/T 20065-2016
GB/T 20065-2016: Screw-thread steel bars for the prestressing of concrete---This is an excerpt. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.), auto-downloaded/delivered in 9 seconds, can be purchased online: https://www.ChineseStandard.net/PDF.aspx/GBT20065-2016
GB
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 77.140.60
H 44
Replacing GB/T 20065-2006
Screw-thread Steel Bars
for the Prestressing of Concrete
(ISO 6934-5.1991, Steel for the Prestressing of Concrete – Part 5.
Hot-rolled Steel Bars with or without Subsequent Processing,
NEQ)
Issued on. DECEMBER 13, 2016
Implemented on. SEPTEMBER 1, 2017
Issued by. General Administration of Quality Supervision, Inspection and
Quarantine of the People's Republic of China;
Standardization Administration of the People's Republic of
China.
Table of Contents
Foreword... 3
1 Application Scope... 5
2 Normative References... 5
3 Terms and Definitions... 7
4 Strength Grade Codes... 7
5 Order Content... 8
6 Dimensions, Shapes, Weights and Permissible Deviations... 8
7 Technical Requirements... 11
8 Test Methods... 12
9 Inspection Rules... 14
10 Packaging, Designation and Quality Certification... 15
Annex A (Normative) Method for the Determination of Total Elongation of
Steel Bars... 16
Foreword
This Standard was drafted in accordance with the rules given in GB/T 1.1-2009.
This Standard replaces GB/T 20065-2006, Screw-thread Steel Bars for the
Prestressing of Concrete. Compared with GB/T 20065-2006, the main technical
changes of this Standard are as follows.
-- it adds nominal diameters;
-- it adds the requirements for chemical elements;
-- it adds strength grades;
-- it unifies the methods for relaxation test; and
-- it gives detailed description for fatigue test.
This Standard was redrafted by reference to ISO 6934-5.1991, Steel for the
Prestressing of Concrete – Part 5.Hot-rolled Steel Bars with or without Subsequent
Processing. It is non-equivalent to ISO 6934-5.1991.
The main differences between this Standard and ISO 6934-5.1991 are as follows.
-- the surface of steel bar in this Standard is threaded and the surface in the
international standard can be plain or ribbed;
-- the classifications of strength grades are different and steel bar of yield strength
grade 785 and grade 1150 are added in this Standard; and
-- the ranges of nominal diameters are different. it is 15 mm to 75 mm in This
Standard and 15 mm to 40 mm in the international standard.
This Standard was proposed by China Machinery Industry Federation.
This Standard shall be under the jurisdiction of the National Standardization Technical
Committee on Steels (SAC/TC 183).
The drafting organizations of this Standard. Central Research Institute of Building and
Construction Co., Ltd., Tianjin Tiantie Zhaer Steel Production Co., Ltd., Shandong
Shiheng Special Steel Group Co., Ltd., Fujian Sangang (Group) Co., Ltd., Wuhu
Xinxing Ductile Iron Pipes Co., Ltd., Shougang Group and China Metallurgical
Information and Standardization Institute.
The main drafters of this Standard. Zhu Jianguo, Shi Guoming, Chen Xin, Li Bingyi,
Wang Changsheng, Liu Jianfeng, Guo Haichang, Di Quankang, Wang Yujie, Zhao
Yingjie, Han Ziguang, Wang Chengjian, Xiao Lijun, Liu Baoshi, Song Hongwei and
Wang Jiyuan.
The editions of the standard replaced by this Standard is as follows.
-- GB/T20065-2006
Screw-thread Steel Bars
for the Prestressing of Concrete
1 Application Scope
This Standard specifies the terms and definitions, strength grade codes, dimensions,
shapes, weights and permissible deviations, technical requirements, test methods,
inspection rules, packaging, designation and quality certification of screw-thread steel
bars for the prestressing of concrete (also called finish-rolled screw-thread steel bars,
hereinafter referred to as steel bars).
This Standard applies to screw-thread steel bars for the prestressing of concrete which
is produced by hot rolling, remained heat treatment or heat treatment after rolling.
2 Normative References
The following referenced documents are indispensable for the application of this
document. For dated references, only the edition dated applies to this document. For
undated references, the latest edition of the referenced documents (including all
amendments) applies to this Standard.
GB/T 222, Permissible Tolerances for Chemical Composition of Steel Products
GB/T 223.5, Steel and Iron - Determination of Acid-soluble Silicon and Total Silicon
Content – Reduced Molybdosilicate Spectrophotometric Method
GB/T 223.11, Iron, Steel and Alloy – Determination of Chromium Content – Visual
Titration or Potentiometric Titration Method
GB/T 223.12, Methods for Chemical Analysis of Iron, Steel and Alloy – The Sodium
Carbonate Separation-diphenyl Carbazide Photometric Method for the
Determination of Chromium Content
GB/T 223.14, Methods for Chemical Analysis of Iron, Steel and Alloy – The N-
Benzoy-N-Phenylhydroxylamine Extraction Photometric Method for the
Determination of Vanadium Content
GB/T 223.16, Methods for Chemical Analysis of Iron, Steel and Alloy – The
Chromotropic Acid Photometric Method for the Determination of Titanium Content
3 Terms and Definitions
For the purpose of this document, the following terms and definitions shall apply.
3.1
screw-thread steel bars
screw-thread steel bars are hot-rolled straight steel bars with discontinuous outer
thread, which can be connected or anchored with coupler and anchorage with internal
thread of a matching shape on any cross section
3.2
nominal circle area
sectional area of steel bars not including screw-thread
4 Strength Grade Codes
The grades of screw-thread steel bars for prestressed concrete are classified by yield
strength and their designation is “PSB” plus the minimum value of yield strength. P, S
and B are the English initials of Prestressing, Screw and Bars. For example.
5 Order Content
Purchase order in accordance with this Standard shall include the following content at
least.
6 Dimensions, Shapes, Weights and Permissible Deviations
6.1 Scope of nominal diameters and recommended diameters
The range of nominal diameters of steel bars is 15 mm to 75 mm; the nominal
diameters of steel bars recommended in this Standard are 25 mm and 32 mm. Steel
bars of other specifications can be supplied in accordance with the requirements of
users.
6.3 The steel bars are threaded without longitudinal rib and the threads on both sides
of steel bars are on the same helix. The profile is as shown in Figure 1.
6.4 Dimensions and permissible deviations of steel bars are specified in Table 2.
6.5 Length and permissible deviation
6.6 Curvature and end
6.6.1 The curvature of steel bars shall not influence normal use; the curvature of steel
bars per meter shall not be greater than 4 mm; and the total curvature shall not be
greater than 4% of the total length of steel bars.
6.7 Weight and permissible deviation
6.7.1 Steel bars are delivered in actual weight or theoretical weight.
7 Technical Requirements
7.1 Chemical composition
7.2 Smelting method
Steels are smelted in an oxygen converter or electric furnace.
7.3 Conditions of delivery
Steel bars are delivered as straight bars in the condition of hot rolling, remained heat
treatment or heat treatment after rolling.
7.4 Mechanical properties
7.5 Non-metallic inclusions
If the purchaser requires, non-metallic inclusion test can be conducted for steel bars
PSB1080 and above as agreed by the supplier and the purchaser. The conformity
levels of all inclusions shall not be higher than 2.0, respectively.
7.6 Surface quality
8 Test Methods
8.1 Test items
The test items, sampling quantity, sampling methods and test methods for each batch
of steel bars are specified in Table 4.
8.2 Tensile strength
8.2.1 Tensile strength shall be carried out on a test piece of steel bar of full section.
It is not allowed to use test pieces whose section is reduced by machining.
8.3 Relaxation test
8.3.1 Stress relaxation property test of steel bars shall be carried out in accordance
with GB/T 21839.
8.4 Fatigue test
8.4.1 The test pieces for fatigue test shall be cut off directly from finished steel bars;
the length of test pieces shall ensure that the distance between two fixtures is not less
than 500 mm.
8.4.2 Steel bars shall withstand, without failure, 2 × 106 cycles of 0.7 Fm to (0.7Fm –
Fr) pulsating load. See the following equation.
8.5 Dimension measurement
In addition to dimension measurement for steel bars, a coupler of matching shape shall
be used to check screwing-in.
9 Inspection Rules
9.1 Inspection and acceptance
The inspection and acceptance of steel bars shall be carried out by the supplier; the
purchaser shall be entitled to carry out inspection.
9.2 Batching rules
Steel bars shall be inspected and accepted by batch; each batch is constituted by steel
bars of the same furnace number, the same specification and the same delivery
conditions; each batch is 60 t.
9.3 Sampling quantity
The sampling quantities for all inspection items of steel bars are specified in Table 4.
9.4 Reinspection and determination
The reinspection and determination of steel bars are specified in GB/T 17505.
9.5 Rounding-off for numerical values
The rounding-off for numerical values and determination of test results are specified in
YB/T 081.
10 Packaging, Designation and Quality Certification
10.1 Designation of steel bars shall conform to the following requirements.
......
Source: Above contents are excerpted from the full-copy PDF -- translated/reviewed by: www.ChineseStandard.net / Wayne Zheng et al.
|