Document: NRC Regulatory Guide
Document ID: 3c238fa7-baa2-41c1-ac85-868fcda6b038
Document Type: regulatory_guide
Title: Design Limits, Loading Combinations, Materials, Construction, and Testing of Concrete Containments + HISTORY – HISTORY 07/2020 – DG-1372 , Proposed Revision 4 05/2019 – Periodic Review of Revision 3 – Revise 10/2015 – Periodic Review of Revision 3 – Reviewed with issues identified for future consideration 10/2006 – DG-1159, Proposed Revision 3 Prior to the issuance of DG-1159, RG 1.136 was entitled "Materials, Construction, and Testing of Concrete Containments (Rev. 4)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML2010/ML20105A215.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.136
CFR Part: 
CFR Title: 

Content:
; annulus pressurization; suppression pool pressures including chugging, condensation oscillation, vent clearing, and pool swell; and jet loads and drag loads acting on submerged structures/components and those above the water surface) should be treated as abnormal pressure loads, Pa. Appropriate load combinations and load factors should be applied accordingly. b. All of the various LOCA-induced loads may be combined in accordance with their actual time-dependent mutual occurrence. A-2. SAFETY/RELIEF VALVE DISCHARGE a. Safety/relief valve (SRV) loads (such as single valve, single valve plus adjacent valve, automatic depressurization system valves, and all valves) should be included in all load combinations as defined in the ASME Boiler and Pressure Vessel Code, Section III, Division 2, Subsection CC. However, for the load combination that contains 1.5 Pa, a load factor of 1.25 should be applied to the appropriate SRV loads. Also, for the severe environmental load combination, the load factor should be 1.3, which is consistent with the practice of treating SRV as a live load. b. A single active failure causing one SRV discharge should be considered in combination with the design-basis accident. c. Appropriate multiple SRV discharges should be considered in combination with the small-break accident and intermediate-break accident. d. Thermal loads resulting from SRV discharge should be treated as To for normal operation and Ta for accident conditions. A-3. COMBINATION OF DYNAMIC LOADS Revision 1 of NUREG-0484, “Methodology for Combining Dynamic Responses” (Ref. A1), presents guidance on the acceptable methods for combining LOCA, SRV, and the safe- shutdown earthquake (SSE). This report states that the square root of sum of the squares method is appropriate for the following: a. Combination of SSE and LOCA dynamic responses for all ASME Class 1, 2, or 3 systems, components, or supports. For dynamic responses resulting from the same DG-1372, Appendix A, Page A-2