Base Connections for Signal/Sign Structures

The Atlantic hurricane season of 2004 brought with it a series of four major hurricanes that made landfall across Florida within a six-week period. During that time, a number of cantilever sign structures along the state interstate system failed. As a result, the Florida Department of Transportation (FDOT) began a series of research initiatives to address this issue. The first research project determined the cause of the failures, the proper design procedure, and a retrofit option. A second suggested a load transfer system to eliminate anchor bolts from the foundation design. The current project suggests a way to also eliminate annular plates from the design of the base connection. The alternative chosen for testing after a literature review was the tapered bolted slip base design. This alternative consists of two main components: a slip joint and through-bolts. The slip joint is designed to transfer flexural loads, while the through-bolts are responsible for transferring torsional loads from the upper pole to the lower pole. The selection of this alternative as a replacement for the anchor bolt and annular plate option has the potential to improve the American Association of State Highway and Transportation Officials (AASHTO) fatigue rating from an E or E' up to a B. The results of the test program give a detailed representation of the behavior of the base connection components. The data and observations during and after testing reveal how the load is transferred along the length of the slip joint and across the through-bolts. The tapered bolted slip base connection has been proven adequate for transferring both flexural and torsional loads as applied to a cantilever signal or sign structure. It is recommended that a number of field specimens be constructed and monitored to better determine the necessary design procedures and confirm the behavior of the base connection as predicted by the results of this test program.

• Record URL:
  https://fdotwww.blob.core.windows.net/sitefinity/docs/default-source/research/reports/fdot-bdk75-977-32-rpt.pdf
• 
• Summary URL:
  https://fdotwww.blob.core.windows.net/sitefinity/docs/default-source/research/reports/fdot-bdk75-977-32-sum.pdf
• Corporate Authors:

  University of Florida, Gainesville

  Department of Civil and Coastal Engineering
  Gainesville, FL  United States  32611-6580

  Florida Department of Transportation

  Research Center
  605 Suwannee Street MS-30
  Tallahassee, FL  United States  32399-0450
• Authors:
  • Cook, Ronald A
  • Prevatt, David O
  • Dalton, Sadie A
• Publication Date: 2012-2

Language

• English

Media Info

• Media Type: Digital/other
• Edition: Final Report
• Features: Appendices; Figures; Photos; References; Tables;
• Pagination: 181p

Subject/Index Terms

• TRT Terms: Anchors (Structural connectors); Cantilevers; Design; Fatigue tests; Guidelines; Load transfer; Sign supports; Structural connection
• Uncontrolled Terms: Annular base plates; Signal supports
• Geographic Terms: Florida
• Subject Areas: Bridges and other structures; Design; Highways; Operations and Traffic Management; I20: Design and Planning of Transport Infrastructure;

Filing Info

• Accession Number: 01370076
• Record Type: Publication
• Report/Paper Numbers: BDK75 977-32, Project No. 00087289
• Contract Numbers: BDK75 977-32
• Files: TRIS, STATEDOT
• Created Date: May 16 2012 3:05PM