Resistance Factors for Drilled Shafts in Weak Rocks Based on O-Cell Test Data

Load and resistance factor design (LRFD) has been mandatory for all FHWA-funded bridges since October 2007. The resistance factors included in the current AASHTO specifications for foundation design are not all calibrated by using field data. A calibration of resistance factors for side resistance of drilled shafts in weak rock is based on the statistical data collected from 19 O-cell tests in the midwestern United States. The field test data were used to determine the measured resistance, and the in situ rock properties and the dimensions of drilled shafts were used to calculate the predicted resistance by using the FHWA method. The Monte Carlo method was selected to perform the calibration. On the basis of the normally distributed loads and log normal distributed resistance from the test data, side resistance factors were determined at a target reliability index of 3.0. The calibrated resistance factors were compared with those in the current "AASHTO LRFD Bridge Design Specifications."

• Record URL:
  • https://doi.org/10.3141/2045-07
• 
• Record URL:
  • https://scholar.google.com/scholar_lookup?title=Resistance+Factors+for+Drilled+Shafts+in+Weak+Rocks+Based+on+O-Cell+Test+Data&author=X.+Yang&author=J.+Han&author=R.+Parsons&author=R.+Henthorne&publication_year=2008
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/9780309113182
• Authors:
  • Yang, Xiaoming
  • Han, Jie
  • Parsons, Robert L
  • Henthorne, Robert W
• Publication Date: 2008

Language

• English

Media Info

• Media Type: Print
• Features: Figures; References; Tables;
• Pagination: pp 62-67
• Monograph Title: Soil Mechanics 2008
• Serial:
  • Transportation Research Record: Journal of the Transportation Research Board
  • Issue Number: 2045
  • Publisher: Transportation Research Board
  • ISSN: 0361-1981

Subject/Index Terms

• TRT Terms: Bridge foundations; Calibration; Load and resistance factor design; Monte Carlo method; Resistance (Mechanics); Rock mechanics; Specifications; Weak rock
• Identifier Terms: AASHTO LRFD Bridge Design Specifications
• Uncontrolled Terms: Drilled shafts; Osterberg cells; Resistance factors
• Geographic Terms: Midwestern States
• Subject Areas: Bridges and other structures; Design; Geotechnology; Highways; I24: Design of Bridges and Retaining Walls; I43: Rock Mechanics;

Filing Info

• Accession Number: 01089244
• Record Type: Publication
• ISBN: 9780309113182
• Files: PRP, TRIS, TRB, ATRI
• Created Date: Feb 27 2008 8:58AM