Document: NRC Regulatory Guide
Document ID: 0b9a3243-ab39-402c-9f4b-215c6e4f79ab
Document Type: regulatory_guide
Title: Inservice Inspection of Ungrouted Tendons in Prestressed Concrete Containments (Rev. 3)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML0037/ML003740007.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.35
CFR Part: 
CFR Title: 

Content:
se caps of all vertical tendons should be visually inspected to detect grease leakage or grease cap deformations. Removal of grease caps is not necessary for this inspection. 3The terms "large spall," "severe scaling," "D-cracking," "deterioration" and "disintegration" are as defined in the American Concrete Institute publication, ACI 201.IR-68, "Guide for Making a Condition Survey of Concrete in Serv ice." The publication can be obtained from the American Concrete Institute, Redford Station, Detroit, Michigan 48219. 1.35-3 3.4. Concrete surrounding visually inspected tendon anchorages should also be checked visually for indications of abnormal material behavior. 4. PRESTRESS MONITORING TESTS Tendons selected as described in Regulatory Po sition 2 should be subjected to liftoff or other equiva lent tests to monitor their prestress. Additionally, the tests should include the following: 4.1. One tendon, randomly selected from each group of tendons during each inspection, should be subjected to necessary detensioning in order to iden tify broken or damaged wires or strands. 4.2. The simultaneous measurement of elonga tion and jacking force during retensioning should be made at a minimum of three approximately equally spaced levels of force between zero and the lock-off force. 5. TENDON MATERIAL TESTS AND INSPECTIONS 5.1. A previously stressed tendon wire or strand from one tendon of each group should be removed for testing and examination over its entire length to determine if evidence of corrosion or other deleteri ous effects is present. At each successive inspection, the samples should be selected from different ten dons. The tendon selected may be the same as that selected for detensioning. In addition, all wires or strands identified as broken should be removed for tensile testing and visual examination. 5.2. Tensile tests should be made on at least three samples cut from each removed wire or strand, one at each end and one at mid-length. The samples should be the