BENDING-FATIGUE TEST ON COMPOSITE BEAMS MODEL OF LIGHTWEIGHT CONCRETE

RECENTLY, THE SO-CALLED LIGHTWEIGHT CONCRETE USING ARTIFICIAL LIGHTWEIGHT AGGREGATE HAS BEEN APPLIED FOR SLABS OF METAL BRIDGES. THE LIGHTWEIGHT CONCRETE HAS TWO DIFFERENT KINDS OF MIX; ONE USES THE LIGHTWEIGHT AGGREGATE ONLY AS COARSE AGGREGATE AND NATURAL RIVER SAND AS FINE AGGREGATE (LS-MIX), AND THE OTHER USES THE LIGHTWEIGHT AGGREGATE AS BOTH COARSE AND FINE AGGREGATES (LL-MIX). THE LATTER MIX IS DESIRABLY SUITABLE FROM THE STANDPOINTS OF DECREASING DEAD LOAD AND COST. THE USE OF LIGHTWEIGHT CONCRETE FOR SLABS OF COMPOSITE METAL GIRDER BRIDGES IS BEING RESEARCHED ON UP TO DATE, AND RESULTS OF THE STATIC LOAD BENDING TEST ON THE SIMPLE COMPOSITE BEAMS MODEL USING LL-MIX AND OF THE REPEATED LOAD BENDING TEST ON THE COMPOSITE BEAMS MODEL USING LS-MIX HAVE BEEN PUBLISHED. THE AUTHORS DESCRIBE HEREWITH THE RESULT OF BENDING-FATIGUE TEST ON COMPOSITE BEAMS OF THE LIGHTWEIGHT CONCRETE SLAB OF LL-MIX. ACCORDING TO THE RESULTS, A SLIGHT CHANGE ON RIGIDITY OF THE GIRDER CAUSED BY THE REPEATED DYNAMIC LOAD HAS BEEN OBSERVED. THIS CHANGE, HOWEVER, AFFECTS NOT SEVERELY THE COMPOSITE BEAMS STRUCTURE. ACCORDINGLY, IT WOULD NOT BE NECESSARY TO CONSIDER THE FATIGUE STRENGTH FOR DESIGNING COMPOSITE BEAMS OF LIGHTWEIGHT CONCRETE WHEN REPETITION OF LOAD APPLICATION, AS MANY AS ONE MILLION TIMES, IS ASSUMED. /AUTHOR/

• Supplemental Notes:
  • pp 15-22, 9 FIG, 10 TAB, 3 PHOT, 7 REF
• Authors:
  • Yamamura, N
  • Ushio, M
  • Oka, M
  • Naruoka, M
• Publication Date: 1968

Media Info

• Serial:
  • Japan Road Association Annual Report of Roads
  • Publisher: Japan Road Association

Subject/Index Terms

• TRT Terms: Accelerated tests; Artificial aggregates; Beams; Bend tests; Coarse aggregates; Composite materials; Dynamic loads; Fatigue tests; Fine aggregates; Girder bridges; Lightweight aggregates; Lightweight concrete; Mix design; Repeated loads; Slabs; Static loads; Stiffness
• Uncontrolled Terms: Composite beams
• Subject Areas: Bridges and other structures; Highways;

Filing Info

• Accession Number: 00209129
• Record Type: Publication
• Files: TRIS
• Created Date: Mar 16 1970 12:00AM