Analysis and Research of Code Revision for Design of Nuclear Safety Related Concrete Structures of Pressurized Water Reactor Nuclear Power Plants in China

NB/T 20012-2010 design requirements for concrete structures related to nuclear safety of PWR nuclear power plants is a standard issued by the National Energy Administration in 2010. It is the top-level standard and important standard for concrete structure design. Due to technological progress and changes in relevant reference standards, some of its contents can not meet the requirements at this stage, On the basis of referring to the latest relevant standards and specifications at home and abroad, the engineering experience in the structural design of nuclear safety related plants of nuclear power plants built and under construction in China was summarized, and the chief editor revised it. This paper mainly analyzes the revised contents, mainly including revising the minimum strength grade of concrete was changed to C30, HRB500, HPB300 steel bars were added, and HPB235, HRB335 steel bars were canceled; improving the safety of the axial compression members that configure the ordinary stirrups, modifying the formula for calculating the bearing capacity of the transverse shear (that is, out-of-plane shear), modifying the formula for calculating the punching bearing capacity (considering the effects of membrane force) ; defining the load effect combination used in the calculation of crack width, and the maximum crack width is calculated according to the relevant specifications of GB 50010; stipulating that short-term stiffness is taken in deflection calculation under normal operation and severe environment, normal operation and extreme environment and abnormal operation conditions; adding contents of structural analysis, basic provisions of mechanism components and beyond the scope of design basis;The Appendix B (informative) “Performance Index of Reinforcement and Concrete at High Temperature” was added;.