REACTIONS OF A TWO-SPAN, SKEWED, RIGID-FRAME BRIDGE, WITH DISCUSSION

THIS INVESTIGATION SEEKS TO ADD CREDENCE TO RATHBUN'S THEORY AND TO POINT OUT SUCH LIMITATIONS AS MAY EXIST, BY MEANS OF EXPERIMENTAL CORRELATION OF REACTIVE FORCES. THE FOLLOWING FACTS WERE BROUGHT OUT: (1) THE VERTICAL REACTIONS Y AND THE HORIZONTAL THRUSTS X ARE ESSENTIALLY INDEPENDENT OF SKEW ANGLE FOR CENTERLINE LOADING AND VARY WITH SKEW ONLY SLIGHTLY FOR OFF-CENTER LOADING; (2) FOR PRACTICAL DESIGN PURPOSES, X AND Y ARE THE SAME AS FOR A SIMILAR RIGHT FRAME OF THE SAME SQUARE SPAN. THE MODEL STUDY COMPLETELY SUBSTANTIATES THE THEORY FOR THESE REACTIONS; (3) CROSS- SHEAR Z IS EQUAL TO THE TANGENT OF THE SKEW ANGLE MULTIPLIED BY THE CORRESPONDING THRUST X; MODEL RESULTS ARE NOT REPORTED FOR THIS REACTION BECAUSE OF MODEL LIMITATIONS, BUT AMPLE EVIDENCE EXISTS TO SUBSTANTIATE THIS FACT; (4) HORIZONTAL MOMENT IS NEGLIGIBLE AND MAY BE NEGLECTED IN DESIGN; AND (5) TORSIONAL MOMENTS SHOW SERIOUS DISCREPANCY WITH THEORY, WITH THEORETICAL VALUES APPARENTLY ON THE UNSAFE SIDE. IT IS BELIEVED THAT THE SAINT VENANT TORSIONAL FACTOR IS NOT APPLICABLE TO SKEWED PLATES HAVING THE PROPORTIONS OF BRIDGE SLABS, AND FUNDAMENTAL INVESTIGATION OF THIS FACTOR IS CONSIDERED TO BE DESIRABLE. /AUTHOR/

• Record URL:
  http://onlinepubs.trb.org/Onlinepubs/hrbresearchrpts/1952/14B-006.pdf
• Supplemental Notes:
  • Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved.
• Corporate Authors:

  Highway Research Board (HRB)

  Washington, DC   
• Authors:
  • Fisher, Gordon P
  • Boyer, Walter C
• Discussers:
  • Plower, Jason
  • Gee, Herbert
  • Erickson, E L
  • Fisher, G P
  • Boyer, W C
• Conference:
  • Thirty-First Annual Meeting of the Highway Research Board
• Publication Date: 1952

Media Info

• Media Type: Digital/other
• Features: Figures; References; Tables;
• Pagination: 11p
• Monograph Title: Distribution of load stresses in highway bridges
• Serial:
  • Highway Research Board Research Reports
  • Issue Number: 14B
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Bridge design; Bridges; Loads; Mathematical models; Skew bridges; Skewed structures; Structural design
• Uncontrolled Terms: Horizontal loads; Loading; Models; Vertical loads
• Old TRIS Terms: Rigid frame bridges
• Subject Areas: Bridges and other structures; Highways;

Filing Info

• Accession Number: 00209602
• Record Type: Publication
• Files: TRIS, TRB
• Created Date: May 22 1972 12:00AM