TENSILE CAPACITY OF ANCHORS WITH PARTIAL OR OVERLAPPING FAILURE SURFACES: EVALUATION OF EXISTING FORMULAS ON AN LRFD BASIS

This study concerns the prediction of tensile capacity, as governed by concrete cone failure, of single anchors located close to a free edge and multiple anchor groups located far from a free edge and installed in uncracked, unreinforced concrete. A total of 160 data points is available for single anchors close to a free edge, while 185 data points are available for multiple anchors. A total of 31 data points consisting of data on high-strength anchors (previously compiled) is accessible from tests on single anchors failing by fracture of the anchor steel. Using common definitions and nomenclature for all variables and material properties, each data set is placed in a database using SI units and concrete cube strengths. The concrete failure data are then compared with capacities predicted by the three existing methods: the 45 deg cone method; a variable angle cone (VAC) method; and the concrete capacity (CC) method. Obsered data are compared against these existing methods in terms of average square error and load and resistance factor design (LRFD). Finally, using the principles of LRFD, and following the design procedure of American Concrete Institute (ACI) 349-90, the probability of steel failure or concrete cone failure under known loads and concrete cone failure under unlimited loads is computed. Based on those comparisons, each procedure is evaluated in terms of accuracy and suitability for use in design. For single anchors located near a free edge and for multiple closely spaced anchors, the CC method fits most of the data better than either the ACI 349-90 method or the VAC method, and gives lower and more consistent probabilities of failure. This is very apparent at very shallow and very deep embedments.

• Record URL:
  http://www.concrete.org/Publications/InternationalConcreteAbstractsPortal.aspx.aspx?m=details&i=9664
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/oclc/13846957
• Corporate Authors:

  American Concrete Institute

  P.O. Box 19150, Redford Station, 22400 Seven Mile Road
  Detroit, MI  United States  48219
• Authors:
  • Farrow, C B
  • Klingner, R E
• Publication Date: 1995-11

Language

• English

Media Info

• Features: Figures; References; Tables;
• Pagination: p. 698-710
• Serial:
  • ACI Structural Journal
  • Volume: 92
  • Issue Number: 6
  • Publisher: American Concrete Institute (ACI)
  • ISSN: 0889-3241
  • Serial URL: http://www.concrete.org/PUBS/JOURNALS/SJHOME.ASP

Subject/Index Terms

• TRT Terms: Bolts; Design; Evaluation; Failure; Load and resistance factor design; Loads; Resistance (Mechanics); Safety; Structural design; Surfaces; Tensile strength
• Uncontrolled Terms: Anchors; Capacity
• Old TRIS Terms: Failure surfaces
• Subject Areas: Bridges and other structures; Design; Highways; Safety and Human Factors; I24: Design of Bridges and Retaining Walls;

Filing Info

• Accession Number: 00715280
• Record Type: Publication
• Files: TRIS
• Created Date: Dec 28 1996 12:00AM