GB/T 36707-2018 (English Version)

Standard No.: GB/T 36707-2018
Language: Chinese, Available in English version
Release Date: 2018
Published By: General Administration of Quality Supervision, Inspection and Quarantine of the People‘s Republic of China
Latest: GB/T 36707-2018

Scope: This standard specifies the classification, grade, ordering content, size, shape, weight and allowable deviation, technical requirements, test methods, inspection rules, packaging, marking and quality certificate of hot-rolled carbon steel-stainless steel composite steel bars for reinforced concrete. This standard applies to stainless steel composite steel bars (hereinafter referred to as "rebars") produced by hot rolling with stainless steel as the cladding and carbon steel (or low alloy steel) as the base material.

Introduction

GB/T 36707—2018 Standard Overview

The National Standard of the People's Republic of China GB/T 36707—2018 "Hot-rolled carbon steel-stainless steel composite steel bars for reinforced concrete" specifies the classification, grade, order content, size, shape, weight and allowable deviation, technical requirements, test methods, inspection rules, packaging, marking and quality certificate of hot-rolled carbon steel-stainless steel composite steel bars for reinforced concrete. This standard applies to stainless steel composite steel bars produced by hot rolling with stainless steel as the cladding and carbon steel (or low alloy steel) as the base material.

Background and significance of standard formulation

With the increasing demand for corrosion resistance and high-strength materials in the construction industry, traditional carbon steel bars have been unable to meet the engineering requirements in complex environments. The introduction of GB/T 36707—2018 fills the domestic standardization gap in the field of stainless steel composite steel bars and provides a better technical solution for construction projects.

Comparison of standard frameworks

Standard dimensions	GB/T 36707—2018	International integration	Technical advantages
Classification and grades	Divided into 300, 400, 500 grades, two types of round and ribbed; the grade composition is clear.	Conforms to the international general standard system and is consistent with the relevant standards of the European Union and ASTM.	Provides a variety of choices to meet different engineering needs.
Technical requirements	Clear indicators such as chemical composition, mechanical properties, coating thickness and bonding.	Some indicators (such as corrosion resistance) are higher than the international average.	Highlight corrosion resistance and high strength characteristics, adapt to harsh environments.
Test methods	Specify specific methods such as chemical composition analysis, stretching, bending, and coating thickness measurement.	In line with ISO standards, some methods are more detailed.	Ensure the accuracy and repeatability of test results.

Explanation of professional terms and practical applications

Compound Contact Interface: refers to the metallurgical bonding surface between the composite steel bar substrate and the coating, which is a key factor in determining material performance. In actual construction, the integrity of this interface must be ensured to prevent corrosion and stress concentration.

Mechanical performance indicators: Such as yield strength and tensile strength, which directly affect the safety of the structure. For example, HRB500SC steel bars have higher yield strength (≥500 MPa) and tensile strength (≥630 MPa), which are suitable for high-load buildings.

Implementation suggestions

Design selection:Choose a suitable grade of composite steel bars according to the engineering environment. For example, S31608 cladding with better corrosion resistance should be preferred in coastal or saline-alkali environments.
Construction precautions:Ensure that the cladding is not damaged during the processing of the steel bars to avoid affecting the corrosion resistance. It is recommended to use mechanical connection methods and use connection materials that match the strength grade of the steel bars.
Quality control:Strictly carry out on-site inspections in accordance with the standards, focusing on the thickness, bonding and mechanical performance indicators of the cladding. It is recommended to introduce non-destructive testing technology (such as ultrasonic thickness measurement) to improve the efficiency of inspection.

GB/T 36707-2018 Referenced Document

GB/T 11170 Stainless steel .Determination of multi-element contents.Spark discharge atomic emission spectrometric method (Routine method)
GB/T 1499.1 Steel for the reinforcement of concrete—Part 1:Hot rolled plain bars
GB/T 1499.2 Steel for the reinforcement of concrete—Part 2:Hot rolled ribbed bars
GB/T 17359 Microbeam analysis of elements with atomic number not less than 11 and energy spectrometry for quantitative analysis*， 2023-12-28 Update
GB/T 20123 Steel and iron - Determination of total carbon and sulfur content Infrared absorption method after combustion in an induction furnace (routine method)
GB/T 20124 Steel and iron - Determination of nitrogen content - Thermal conductimetric method after fusion in a current of inert gas (Routine method)
GB/T 20125 Low-alloy steel.Determination of multi-element contents.Inductively coupled plasma atomic emission spectrometric method
GB/T 20878 Stainless steels——Designation and chemical composition*， 2024-07-24 Update
GB/T 2101 General requirment of acceptance, packaging, marking and certification for section steel
GB/T 222 Permissible tolerances for chemical composition of steel products
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 223.19 Methods for chemical analysis of iron,steel and alloy--The neocuproine-chloroform extraction photometric method for the determination of copper content
GB/T 223.23 Iron,,steel and alloy.Determination of nickel content.The dimethylglyoxime spectrophotometric method
GB/T 223.26 Iron,steel and alloy.Determination of molybdenum content.The thiocyanate spectrophotometric method
GB/T 223.28 Methods for chemical analysis of iron,steel and alloy--The α-benzoinoxime gravimetric method for the determination of molybdenum content
GB/T 223.36 Methods for chemical analysis of iron, steel and alloy. The neutral titration method for the determinaion of nitrogen content after distillation separation
GB/T 223.37 Iron, steel and alloy—Determination of nitrogen content—Indophenol blue spectrophotometric method after distillation separation*， 2020-06-02 Update
GB/T 223.40 Iron, steel and alloy Determination of niobium content by the sulphochlorophenol S spectrophotometric method
GB/T 223.5 Steel and iron.Determination of acid-soluble silicon and total silicon content.Reduced molybdosilicate spectrophotometric method
GB/T 223.58 Methods for chemical analysis of iron,steel and alloy--The sodium arsenite-sodium nitrite titrimetric method for the determination of manganese content
GB/T 223.60 Steel and alloys - Determination of silicon content - Gravimetric method*， 2024-04-25 Update
GB/T 223.63 Iron, steel and alloy—Determination of manganese content—Sodium (potassium) periodate spectrophotometric method*， 2022-07-11 Update
GB/T 223.67 Iron,steel and alloy.Determination of sulfur content.Methylene blue spectrophotometric method
GB/T 223.68 Methods for chemical analysis of iron, steel and alloy. The potassium iodate titration method after combustion in the pipe furnace for the determination of sulfur content
GB/T 223.69 Iron,steel and alloy.Determination of carbon contents.Gas-volumetric method after combustion in the pipe furnace
GB/T 28900 Test methods of steel for reinforcement of concrete*， 2022-10-12 Update
GB/T 4334 Corrosion of metals and alloys－Test methods for intergranular corrosion of austenitic and ferritic-austenitic (duplex) stainless steels*， 2020-04-28 Update
GB/T 4336 Determination of multi-element content in carbon steel and medium and low alloy steel Spark discharge atomic emission spectrometry (conventional method) Amendment No. 1
GB/T 6462 Metallic and oxide coatings-Measurement of coating thinckness-Microscopical method
YB/T 081 Rule for rounding off of numberical values and judgement of testing values for technical standards of metallurgy

GB/T 36707-2018 history

2018 GB/T 36707-2018 Hot rolled carbon steel and stainless steel clad bars for the reinforcement of concrete