The Relationship between Torque, Tension, and Nut Rotation of Large Diameter Anchor Bolts

The purpose of this investigation was to determine the relationship between torque, tension and nut rotation of the large-diameter anchor bolts used on cantilever sign supports. This research was in response to concerns about loose nuts found o these anchor bolts during field inspection of in-service sign supports, along with concerns regarding an unspecified tightening procedure. Results of this investigation were used to determine the appropriate anchor-bolt tightening procedure and to determine whether or not turning the nut past the snug position imparts the desired amount of tension in the anchor bolt. This investigation also determined the appropriate torque for checking anchor-bolt installations in the field, the effects of bolt relaxation, and any problems of thread stripping from tightening.

• Record URL:
  https://mdotjboss.state.mi.us/SpecProv/getDocumentById.htm?docGuid=0e39c06b-2b9f-451a-9b14-bb73ed0dc1a4
• 
• Corporate Authors:

  Michigan Department of Transportation

  Construction and Technology Division, P.O. Box 30049
  Lansing, MI  United States  48909

  Michigan Transportation Commission

  P.O. Box 30050
  Lansing, MI  United States  48909
• Authors:
  • Till, Roger D
  • Lefke, Nadege A
• Publication Date: 1994-10

Language

• English

Media Info

• Media Type: Web
• Features: Figures; Tables;
• Pagination: 17p

Subject/Index Terms

• TRT Terms: Anchor bolts; Anchorages; Cantilevers; Nuts (Fasteners); Sign supports; Tension; Torque
• Geographic Terms: Michigan
• Subject Areas: Highways; Maintenance and Preservation; I60: Maintenance;

Filing Info

• Accession Number: 01115773
• Record Type: Publication
• Report/Paper Numbers: Research Report R-1330
• Contract Numbers: Research Project 91 TI-1556
• Files: TRIS, STATEDOT
• Created Date: Nov 29 2008 8:07AM