Document: NRC Regulatory Guide
Document ID: fcaa3426-5268-4adb-a83c-69e7f50d6d6b
Document Type: regulatory_guide
Title: Anchoring Components and Structural Supports in Concrete (Rev. 1)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1725/ML17258A579.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.199
CFR Part: 
CFR Title: 

Content:
t. c. Drill hole angularity in concrete is within established limits. d. Bolt hole has been cleared of drill dust. e. Anchor has been correctly preloaded. 2. Inspection Licensees and applicants should use their construction inspectors with the training and qualifications specified by the licensed design professional and anchor manufacturer. All anchors should be inspected to verify that they are of the specified size and type. Anchor systems that are external (that part or portion of the anchor that is not embedded in the concrete-visible part) to the concrete surface should be inspected to assure adequate performance during the life of the structure. In addition to the provisions in Section D.9.2 of Appendix D to ACI 349-13, the following 6-step inspection program should be used to verify the proper installation of post-installed anchors: 2.1 Are the nut and anchor bolt tight? This step will detect certain types of installation defects: oversized holes, total lack of preload, loose nuts, damaged subsurface concrete, DG-1284, Page 7 and missing plug (for shell type). To implement this step, it is necessary to place a calibrated device on the bolt head or nut and to apply a torque. A well-installed bolt should not rotate under the torque applied equal to about 20 percent of the normal installation torque. 2.2 Are there washers between the equipment base and the anchor bolt nut or bolt head? All bolts should have washers. Oversize washers should be used for thin equipment bases. Lock washers should be used where even low-level vibration exists. 2.3 Is the bolt spacing in accordance with the anchorage design? 2.4 Is the distance between the bolt and any free concrete surface in accordance with the anchorage design (edge condition)? 2.5 Is the concrete sound and uncracked? This inspection element will detect gross defects in the concrete that could affect the holding power of expansion anchor bolts. Hairline shrinkage cracks in the vicinity of an expansion bolt are not