GB/T 47513-2026 Design analysis of cavity radiation streaming shielding for pressurized water reactor nuclear power plants 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
CCS
National Standard of the People's Republic of China
GB/T 47513-2026
Design analysis of cavity radiation streaming shielding for pressurized water reactor nuclear power plants
压水堆核电厂反应堆堆腔辐射漏束屏蔽设计分析
Issue date: 2026-04-30 Implementation date: 2026-11-01
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 and Definitions
4 General Requirements
5 Calculation Method Requirements .
6 Input Data Requirements
7 Calculation Verification and Uncertainty Analysis
Annex A (Informative) Example of Shielding Design Analysis for Radiation Streaming from the Reactor Cavity of a Pressurized Water Reactor Nuclear Power Plant
Annex B (Informative) Monte Carlo Source Multiplication Method
Annex C (Informative) Discrete Ordinates Monte Carlo Segmented Linear Calculation Method
Annex D (Informative) Monte Carlo Transport Calculation Method Using Variance Parameters Generated by a Discrete Ordinates Code
Annex E (Informative) Calculation Verification Method
Annex F (Informative) Uncertainty Analysis Method for Radiation Streaming Calculation from the Reactor Cavity
Bibliography
Shielding design analysis for radiation streaming from the reactor cavity of pressurized water reactor nuclear power plants
1 Scope
This document specifies the requirements for the shielding design analysis method, calculation scope, design input and result analysis for radiation streaming from the reactor cavity of pressurized water reactor nuclear power plants.
This document applies to the shielding design calculation and analysis for radiation streaming from the reactor cavity of pressurized water reactor nuclear power plants under full power operation and shutdown conditions. Other reactor types may refer to this document.
2 Normative References
This document has no normative references.
3 Terms and definitions
The following terms and definitions apply to this document.
3.1 reactor cavity
A cavity, typically consisting of thick walled reinforced concrete radiation shielding structures, that encloses the reactor pressure vessel.
3.2 reactor cavity radiation streaming
Particle streams (neutrons and photons) that penetrate from the reactor core into the reactor cavity and, not being fully shielded, leak through cavity passages, penetrations, labyrinths and other paths to other rooms and areas of the reactor building.
4 General requirements
4.1
The shielding design analysis for reactor cavity radiation streaming shall consider the potential radiation impact of all reactor cavity radiation streaming paths affecting the target assessment area. Target assessment areas include the reactor cavity, areas where important equipment is located, and other specific areas of concern. Annex A, taking a typical third generation passive pressurized water reactor nuclear power plant as an example, introduces the main streaming paths for reactor cavity radiation streaming and the general considerations for shielding design.
4.2 Based on the calculation requirements for the target assessment area, the required physical quantities during reactor power operation and after shutdown shall be given, such as neutron fluence rate, neutron dose rate and photon dose rate.
4.3 The shielding design analysis for reactor cavity radiation streaming shall use a currently mature and engineering validated shielding calculation method. It shall be demonstrated that the calculation method is applicable to transport calculations involving large, complex geometries and coupled sub zones. Monte Carlo transport calculation methods or discrete ordinates Monte Carlo coupled transport calculation methods should be used. If a Monte Carlo transport calculation method is used for the analysis, a validated variance reduction method should be employed.
4.4 Cross section data shall be obtained from a validated database applicable to pressurized water reactors.
4.5 Radiation sources and structures involved in the design analysis, such as the core, equipment, systems and buildings, should be accurately modelled. If simplifications or approximations are made, their rationality and conservatism shall be ensured.
4.6 An uncertainty analysis of the calculation results shall be performed.
5 Calculation method requirements
5.1 When using Monte Carlo transport calculation methods for shielding design analysis of radiation streaming from the reactor cavity, techniques such as source biasing, geometry splitting/roulette, energy cut off, Monte Carlo surface source continuation, forward Monte Carlo generated weight windows, and adjoint Monte Carlo generated weight windows may be used. When using these calculation methods, the following requirements shall be met:
a)The source biasing method shall be validated by comparison with an unbiased calculation.
b) When using geometry splitting/roulette, the importance ratio between adjacent cells should not exceed a factor of 4, and the cell radius should not be less than 2 mean free paths. The method shall be validated by comparison with an unbiased calculation of a typical problem.
c) When using an energy cut off, the deviation introduced by the cut off shall be determined by comparison with a calculation without cut off, and the results of the energy cut off calculation shall be adjusted to eliminate the deviation.
d) Monte Carlo surface source continuation: when using the surface source continuation function for segmented calculation by setting intermediate continuation surfaces, volume overlap regions in each calculation step shall be considered and checked for appropriateness. The number of continuation surfaces should be minimised and truncation of the source distribution should be avoided. Furthermore, the choice of boundary conditions for the segmented calculation shall be fully considered and checked for appropriateness. Annex B provides a detailed description of this method.
e) When using the weight window method for Monte Carlo variance reduction, it shall be validated by comparison with a calculation without variance reduction techniques.
f) The influence of the size of the tally region on the calculated fluence rate results shall be analysed. If the size of the tally region introduces a significant bias into the calculation, the tally region should be reduced and the number of sampled particles increased for a recalculation. When using a point detector, if an average fluence rate region (the region corresponding to the point detector‘s finite size) is defined for variance reduction, the calculated fluence rate should ideally be independent of the choice of the average fluence rate region. If the size of the average fluence rate region introduces a bias into the fluence rate calculation, a smaller average fluence rate region should be used and the number of sampled particles increased for a recalculation. The average fluence rate region surrounding the point detector should not contain any material boundaries.
g) Convergence shall be ensured, and the statistical error of the final calculation result should preferably not exceed 10 %.
5.2 When using the discrete ordinates Monte Carlo coupled transport calculation method for shielding design analysis of radiation streaming from the reactor cavity of a pressurised water reactor nuclear power plant, the output results of the two dimensional discrete ordinates code, the three dimensional discrete ordinates code, and the three dimensional discrete ordinates code can be used as references for the calculation.
Standard
GB/T 47513-2026 Design analysis of cavity radiation streaming shielding for pressurized water reactor nuclear power plants (English Version)
Standard No.
GB/T 47513-2026
Status
valid
Language
English
File Format
PDF
Word Count
14500 words
Price(USD)
435.0
Implemented on
2026-4-30
Delivery
via email in 1~5 business day
Detail of GB/T 47513-2026
Standard No.
GB/T 47513-2026
English Name
Design analysis of cavity radiation streaming shielding for pressurized water reactor nuclear power plants
GB/T 47513-2026 Design analysis of cavity radiation streaming shielding for pressurized water reactor nuclear power plants 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
CCS
National Standard of the People's Republic of China
GB/T 47513-2026
Design analysis of cavity radiation streaming shielding for pressurized water reactor nuclear power plants
压水堆核电厂反应堆堆腔辐射漏束屏蔽设计分析
Issue date: 2026-04-30 Implementation date: 2026-11-01
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 and Definitions
4 General Requirements
5 Calculation Method Requirements .
6 Input Data Requirements
7 Calculation Verification and Uncertainty Analysis
Annex A (Informative) Example of Shielding Design Analysis for Radiation Streaming from the Reactor Cavity of a Pressurized Water Reactor Nuclear Power Plant
Annex B (Informative) Monte Carlo Source Multiplication Method
Annex C (Informative) Discrete Ordinates Monte Carlo Segmented Linear Calculation Method
Annex D (Informative) Monte Carlo Transport Calculation Method Using Variance Parameters Generated by a Discrete Ordinates Code
Annex E (Informative) Calculation Verification Method
Annex F (Informative) Uncertainty Analysis Method for Radiation Streaming Calculation from the Reactor Cavity
Bibliography
Shielding design analysis for radiation streaming from the reactor cavity of pressurized water reactor nuclear power plants
1 Scope
This document specifies the requirements for the shielding design analysis method, calculation scope, design input and result analysis for radiation streaming from the reactor cavity of pressurized water reactor nuclear power plants.
This document applies to the shielding design calculation and analysis for radiation streaming from the reactor cavity of pressurized water reactor nuclear power plants under full power operation and shutdown conditions. Other reactor types may refer to this document.
2 Normative References
This document has no normative references.
3 Terms and definitions
The following terms and definitions apply to this document.
3.1 reactor cavity
A cavity, typically consisting of thick walled reinforced concrete radiation shielding structures, that encloses the reactor pressure vessel.
3.2 reactor cavity radiation streaming
Particle streams (neutrons and photons) that penetrate from the reactor core into the reactor cavity and, not being fully shielded, leak through cavity passages, penetrations, labyrinths and other paths to other rooms and areas of the reactor building.
4 General requirements
4.1
The shielding design analysis for reactor cavity radiation streaming shall consider the potential radiation impact of all reactor cavity radiation streaming paths affecting the target assessment area. Target assessment areas include the reactor cavity, areas where important equipment is located, and other specific areas of concern. Annex A, taking a typical third generation passive pressurized water reactor nuclear power plant as an example, introduces the main streaming paths for reactor cavity radiation streaming and the general considerations for shielding design.
4.2 Based on the calculation requirements for the target assessment area, the required physical quantities during reactor power operation and after shutdown shall be given, such as neutron fluence rate, neutron dose rate and photon dose rate.
4.3 The shielding design analysis for reactor cavity radiation streaming shall use a currently mature and engineering validated shielding calculation method. It shall be demonstrated that the calculation method is applicable to transport calculations involving large, complex geometries and coupled sub zones. Monte Carlo transport calculation methods or discrete ordinates Monte Carlo coupled transport calculation methods should be used. If a Monte Carlo transport calculation method is used for the analysis, a validated variance reduction method should be employed.
4.4 Cross section data shall be obtained from a validated database applicable to pressurized water reactors.
4.5 Radiation sources and structures involved in the design analysis, such as the core, equipment, systems and buildings, should be accurately modelled. If simplifications or approximations are made, their rationality and conservatism shall be ensured.
4.6 An uncertainty analysis of the calculation results shall be performed.
5 Calculation method requirements
5.1 When using Monte Carlo transport calculation methods for shielding design analysis of radiation streaming from the reactor cavity, techniques such as source biasing, geometry splitting/roulette, energy cut off, Monte Carlo surface source continuation, forward Monte Carlo generated weight windows, and adjoint Monte Carlo generated weight windows may be used. When using these calculation methods, the following requirements shall be met:
a)The source biasing method shall be validated by comparison with an unbiased calculation.
b) When using geometry splitting/roulette, the importance ratio between adjacent cells should not exceed a factor of 4, and the cell radius should not be less than 2 mean free paths. The method shall be validated by comparison with an unbiased calculation of a typical problem.
c) When using an energy cut off, the deviation introduced by the cut off shall be determined by comparison with a calculation without cut off, and the results of the energy cut off calculation shall be adjusted to eliminate the deviation.
d) Monte Carlo surface source continuation: when using the surface source continuation function for segmented calculation by setting intermediate continuation surfaces, volume overlap regions in each calculation step shall be considered and checked for appropriateness. The number of continuation surfaces should be minimised and truncation of the source distribution should be avoided. Furthermore, the choice of boundary conditions for the segmented calculation shall be fully considered and checked for appropriateness. Annex B provides a detailed description of this method.
e) When using the weight window method for Monte Carlo variance reduction, it shall be validated by comparison with a calculation without variance reduction techniques.
f) The influence of the size of the tally region on the calculated fluence rate results shall be analysed. If the size of the tally region introduces a significant bias into the calculation, the tally region should be reduced and the number of sampled particles increased for a recalculation. When using a point detector, if an average fluence rate region (the region corresponding to the point detector‘s finite size) is defined for variance reduction, the calculated fluence rate should ideally be independent of the choice of the average fluence rate region. If the size of the average fluence rate region introduces a bias into the fluence rate calculation, a smaller average fluence rate region should be used and the number of sampled particles increased for a recalculation. The average fluence rate region surrounding the point detector should not contain any material boundaries.
g) Convergence shall be ensured, and the statistical error of the final calculation result should preferably not exceed 10 %.
5.2 When using the discrete ordinates Monte Carlo coupled transport calculation method for shielding design analysis of radiation streaming from the reactor cavity of a pressurised water reactor nuclear power plant, the output results of the two dimensional discrete ordinates code, the three dimensional discrete ordinates code, and the three dimensional discrete ordinates code can be used as references for the calculation.
