STRESSES IN CONCRETE PAVEMENT SLABS

THE IOWA ENGINEERING EXPERIMENT STATION HAS CONDUCTED A RESEARCH PROJECT FOR SEVERAL YEARS ON STRESSES IN CONCRETE PAVEMENT SLABS. THIS SECOND PROGRESS REPORT GAVE THE RESULTS OF SOME EXTENSIVE STRAIN MEASUREMENTS FROM WHICH THE MAGNITUDE AND DIRECTION OF THE PRINCIPAL STRESSES WERE DETERMINED AT A LARGE NUMBER OF POINTS IN THE VICINITY OF LOADS APPLIED AT A CORNER OF TWO FULL SCALE MODEL SLABS. THE SUBGRADE REACTION PRESSURES AND DEFLECTIONS OF ONE OF THE SLABS HAVE BEEN MEASURED AT A NUMBER OF POINTS OVER THE CORNER REGION AND THE RATIO BETWEEN PRESSURE AND DEFLECTION AT EACH OF THE POINTS DETERMINED. THESE STUDIES SHOW THAT, FOR THIS SLAB, THE RATIO WAS CONSTANT AT EACH POINT WITHIN THE RANGE OF LOADS APPLIED, BUT WAS NOT THE SAME CONSTANT AT ALL POINTS SINCE IT VARIED WITH THE DISTANCE OF A POINT FROM THE CORNER. THE VALUES OF THE RATIO VARIED FROM ABOUT 300 LB. PER SQ. IN. PER IN. AT THE CORNER TO ABOUT 75 LB. PER SQ. IN. PER IN. AT DISTANCES OF 4.5 FT. FROM THE CORNER. THE USE OF A UNIFORM VALUE OF THE RATIO APPEARS TO BE A JUSTIFIABLE ASSUMPTION FOR ANALYTICAL SOLUTIONS, HOWEVER, SINCE AVERAGE NORMAL STRESSES CALCULATED BY FORMULAS USING A UNIFORM VALUE OF OF 200 CHECKED CLOSELY WITH AVERAGE NORMAL STRESSES CALCULATED FROM MEASURED STRAINS, AND ALSO THOSE CALCULATED FROM MEASURED PRESSURES. /AUTHOR/

• Record URL:
  https://onlinepubs.trb.org/Onlinepubs/hrbproceedings/17/17Pt1-013.pdf
• Supplemental Notes:
  • Vol 17, ParT I, PP 215-234, FIG, 2 TAB, 3 PHOT, 9 REF. 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.
• Authors:
  • Spangler, M G
  • Lightburn, F E
  • BERNHARD, R K
  • Bradbury, R D
• Publication Date: 1938

Media Info

• Media Type: Digital/other
• Monograph Title: Proceedings of the Seventeenth Annual Meeting of the Highway Research Board Held at Washington, D.C. November 30, December 1, 2, 3, 1937. Part I
• Serial:
  • Highway Research Board Proceedings
  • Volume: 17
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Coefficient of subgrade reaction; Concrete pavements; Deflection; Loads; Pressure; Ratios; Slabs; Strain measurement; Stresses
• Subject Areas: Highways; Pavements;

Filing Info

• Accession Number: 00207175
• Record Type: Publication
• Files: TRIS, TRB
• Created Date: Aug 15 1971 12:00AM