GB/T 31545-2025 Portland cement for nuclear power engineering English, Anglais, Englisch, Inglés, えいご
This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered.
ICS 13.220
CCS H 57
National Standard of the People's Republic of China
GB/T 31545-2025
Replaces GB/T 31545-2015
Portland cement for nuclear power engineering
核电工程用硅酸盐水泥
Issue date: 2025-10-31 Implementation date: 2026-05-01
Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
the Standardization Administration of the People's Republic of China
Contents
Foreword
1 Scope
2 Normative References
3 Terms, Definitions and Abbreviations
4 Composition and Materials
5 Designation and Strength Grades
6 Technical Requirements
References
1 Scope
This document specifies the composition and materials, designation and strength grades, technical requirements, test methods, inspection rules, delivery and acceptance, packaging, marking, transportation, and storage for Portland cement for nuclear power engineering (hereinafter referred to as "nuclear power cement").
This document applies to nuclear power cement.
2 Normative References
The contents of the following documents, through normative citations in this document, constitute essential provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including all amendments) applies.
GB/T 176 Methods for chemical analysis of cement
GB/T 750 Autoclave test method for soundness of cement
GB/T 1346 Test methods for water requirement of normal consistency, setting time and soundness of cement
GB/T 5483 Natural gypsum
GB 6566 Limit of radioactive nuclides in building materials
GB/T 8074 Test method for fineness of cement by air permeability (Blaine method)
GB/T 9774 Cement bags
GB/T 12573 Sampling method for cement
GB/T 12959 Test method for heat of hydration of cement
GB/T 17671 Methods of testing cement — Determination of compressive strength (ISO method)
GB/T 21372 Portland cement clinker
GB/T 26748 Cement grinding aid
GB 31893 Limit and test method for water-soluble chromium (VI) in cement
JC/T 603 Test method for drying shrinkage of cement mortar
3 Terms and Definitions
The following terms and definitions apply to this document.
3.1 Portland Cement for Nuclear Power Engineering
A hydraulic cementitious material for nuclear power engineering, produced by grinding Portland cement clinker of appropriate composition with gypsum, characterized by medium heat of hydration and low drying shrinkage.
4 Composition and Materials
4.1 Clinker
The content of tricalcium silicate (C3S) shall not exceed 57.0% by mass, the content of tricalcium aluminate (C3A) shall not exceed 7.0% by mass, and the content of free lime (f-CaO) shall not exceed 1.0% by mass.
4.2 Natural Gypsum
Shall comply with the provisions of GB/T 5483.
4.3 Cement Grinding Aid
Cement grinding aid may be added during the grinding of nuclear power cement, and its addition shall not exceed 0.5% of the mass of nuclear power cement. The cement grinding aid shall comply with the provisions of GB/T 26748.
5 Designation and Strength Grades
Nuclear power cement is designated as P.N with a strength grade of 42.5.
6 Technical Requirements
6.1 Chemical Composition Requirements
6.1.1 Magnesium Oxide (MgO)
The content of magnesium oxide shall not exceed 5.0% by mass. If the autoclave soundness test of nuclear power cement is passed, the content of magnesium oxide in the cement may be increased to not more than 6.0% by mass.
6.1.2 Insoluble Residue (IR)
The content of insoluble residue shall not exceed 0.75% by mass.
6.1.3 Sulfur Trioxide (SO3)
The content of sulfur trioxide shall not exceed 3.0% by mass.
6.1.4 Loss on Ignition (LOI)
The loss on ignition shall not exceed 3.0% by mass.
6.1.5 Chloride Ion (Cl-)
The content of chloride ion shall not exceed 0.06% by mass.
6.2 Water-Soluble Chromium (VI) in Cement
The water-soluble chromium (VI) in nuclear power cement shall comply with the provisions of GB 31893.
6.3 Alkali Content
The alkali content in nuclear power cement shall not exceed 0.60% by mass. The alkali content in nuclear power cement shall be expressed as the calculated value of ω(Na2O) + 0.658ω(K2O).
6.4 Physical Properties
6.4.1 Specific Surface Area
The specific surface area shall be not less than 280 m²/kg and not more than 400 m²/kg.
6.4.2 Setting Time
The initial setting time shall be not less than 45 minutes, and the final setting time shall be not more than 390 minutes.
6.4.3 Boiling Soundness
The boiling soundness shall be qualified.
6.4.4 Drying Shrinkage
The 28-day drying shrinkage shall be not more than 0.10%.
6.4.5 Strength
The strength of nuclear power cement at all ages shall comply with the requirements of Table 1.
Table 1 Strength Requirements for Nuclear Power Cement at Various Ages
Standard
GB/T 31545-2025 Portland cement for nuclear power engineering (English Version)
GB/T 31545-2025 Portland cement for nuclear power engineering English, Anglais, Englisch, Inglés, えいご
This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered.
ICS 13.220
CCS H 57
National Standard of the People's Republic of China
GB/T 31545-2025
Replaces GB/T 31545-2015
Portland cement for nuclear power engineering
核电工程用硅酸盐水泥
Issue date: 2025-10-31 Implementation date: 2026-05-01
Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
the Standardization Administration of the People's Republic of China
Contents
Foreword
1 Scope
2 Normative References
3 Terms, Definitions and Abbreviations
4 Composition and Materials
5 Designation and Strength Grades
6 Technical Requirements
References
1 Scope
This document specifies the composition and materials, designation and strength grades, technical requirements, test methods, inspection rules, delivery and acceptance, packaging, marking, transportation, and storage for Portland cement for nuclear power engineering (hereinafter referred to as "nuclear power cement").
This document applies to nuclear power cement.
2 Normative References
The contents of the following documents, through normative citations in this document, constitute essential provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including all amendments) applies.
GB/T 176 Methods for chemical analysis of cement
GB/T 750 Autoclave test method for soundness of cement
GB/T 1346 Test methods for water requirement of normal consistency, setting time and soundness of cement
GB/T 5483 Natural gypsum
GB 6566 Limit of radioactive nuclides in building materials
GB/T 8074 Test method for fineness of cement by air permeability (Blaine method)
GB/T 9774 Cement bags
GB/T 12573 Sampling method for cement
GB/T 12959 Test method for heat of hydration of cement
GB/T 17671 Methods of testing cement — Determination of compressive strength (ISO method)
GB/T 21372 Portland cement clinker
GB/T 26748 Cement grinding aid
GB 31893 Limit and test method for water-soluble chromium (VI) in cement
JC/T 603 Test method for drying shrinkage of cement mortar
3 Terms and Definitions
The following terms and definitions apply to this document.
3.1 Portland Cement for Nuclear Power Engineering
A hydraulic cementitious material for nuclear power engineering, produced by grinding Portland cement clinker of appropriate composition with gypsum, characterized by medium heat of hydration and low drying shrinkage.
4 Composition and Materials
4.1 Clinker
The content of tricalcium silicate (C3S) shall not exceed 57.0% by mass, the content of tricalcium aluminate (C3A) shall not exceed 7.0% by mass, and the content of free lime (f-CaO) shall not exceed 1.0% by mass.
4.2 Natural Gypsum
Shall comply with the provisions of GB/T 5483.
4.3 Cement Grinding Aid
Cement grinding aid may be added during the grinding of nuclear power cement, and its addition shall not exceed 0.5% of the mass of nuclear power cement. The cement grinding aid shall comply with the provisions of GB/T 26748.
5 Designation and Strength Grades
Nuclear power cement is designated as P.N with a strength grade of 42.5.
6 Technical Requirements
6.1 Chemical Composition Requirements
6.1.1 Magnesium Oxide (MgO)
The content of magnesium oxide shall not exceed 5.0% by mass. If the autoclave soundness test of nuclear power cement is passed, the content of magnesium oxide in the cement may be increased to not more than 6.0% by mass.
6.1.2 Insoluble Residue (IR)
The content of insoluble residue shall not exceed 0.75% by mass.
6.1.3 Sulfur Trioxide (SO3)
The content of sulfur trioxide shall not exceed 3.0% by mass.
6.1.4 Loss on Ignition (LOI)
The loss on ignition shall not exceed 3.0% by mass.
6.1.5 Chloride Ion (Cl-)
The content of chloride ion shall not exceed 0.06% by mass.
6.2 Water-Soluble Chromium (VI) in Cement
The water-soluble chromium (VI) in nuclear power cement shall comply with the provisions of GB 31893.
6.3 Alkali Content
The alkali content in nuclear power cement shall not exceed 0.60% by mass. The alkali content in nuclear power cement shall be expressed as the calculated value of ω(Na2O) + 0.658ω(K2O).
6.4 Physical Properties
6.4.1 Specific Surface Area
The specific surface area shall be not less than 280 m²/kg and not more than 400 m²/kg.
6.4.2 Setting Time
The initial setting time shall be not less than 45 minutes, and the final setting time shall be not more than 390 minutes.
6.4.3 Boiling Soundness
The boiling soundness shall be qualified.
6.4.4 Drying Shrinkage
The 28-day drying shrinkage shall be not more than 0.10%.
6.4.5 Strength
The strength of nuclear power cement at all ages shall comply with the requirements of Table 1.
Table 1 Strength Requirements for Nuclear Power Cement at Various Ages
