STRENGTH AND CRACKING CHARACTERISTICS OF BEAMS WITH #14 AND #18 BARS SPLICED WITH MECHANICAL SPLICES

TESTS OF SIX BEAMS REINFORCED WITH LARGE DIAMETER DEFORMED BARS ARE DESCRIBED. THE BARS IN FOUR OF THE BEAMS WERE SPLICED WITH MECHANICAL SPLICES. THE TEST RESULTS HAVE DEMONSTRATED THAT THE BEHAVIOR OF BEAMS WITH BARS SPLICED BY MECHANICAL SPLICES CAN BE UNDERSTOOD IN TERMS OF ORDINARY THEORIES DEVELOPED FOR REINFORCED CONCRETE. HOWEVER, IT IS EMPHASIZED THAT, TO GET A REALISTIC UNDERSTANDING OF PHENOMENA IN THE MEMBER, THE RELATIVE MOVEMENT OF THE BAR WITH RESPECT TO THE SPLICE SLEEVE SHOULD BE TREATED AS A CONCENTRATED DEFORMATION AND NOT AS A STRAIN. THE RESPONSE OF THE BEAMS WITH TWO-THIRDS OF THE REINFORCEMENT SPLICED AT ONE SECTION AND ONE-THIRD AT ANOTHER SECTION WAS VIRTUALLY IDENTICAL TO THAT OF THE BEAM WITHOUT ANY SPLICES. ANY DIFFERENCES IN STRENGTH, STRAIN DISTRIBUTION, AND CRACKING WERE NEGLIGIBLE. SPLICING ALL BARS AT THE SAME SECTION DID PRODUCE MEASURABLE DIFFERENCES IN DEFLECTIONS AND CRACKING BUT NOT IN STRENGTH. THE RESPONSE OF SUCH A BEAM CAN BE ESTIMATED; RULES ARE GIVEN FOR THE PROCEDURE. THE MEASURED CRACK WIDTHS INDICATED THAT THE EXPRESSION DEVELOPED BY GERGELY AND LUTZ WAS APPLICABLE TO BEAMS REINFORCED WITH NO. 14 AND NO. 18 BARS FOR NONREPEATED SHORT-TIME LOADS. THE REFERENCE CRACK WIDTH, DEFINED AS THE MEAN CRACK WIDTH PLUS TWO STANDARD DEVIATIONS, CAN BE REPRESENTED CONSERVATIVELY BY A SIMPLE EXPRESSION, I.E. THE REFERENCE CRACK WIDTH IS EQUAL TO ONE-FIFTH THE PRODUCT OF THE REINFORCEMENT STRESS AND REINFORCEMENT SIDE COVER.

• Supplemental Notes:
  • Vol 66, No 12, PP 949-957, 5 FIG, 2 TAB, 5 REF, 1 APP
• Authors:
  • Sozen, M A
  • Gamble, W L
• Publication Date: 1969-12

Media Info

• Serial:
  • Am Concrete Inst Journal & Proceedings

Subject/Index Terms

• TRT Terms: Bars (Building materials); Beams; Deflection; Deformation; Fracture mechanics; Material reinforcement; Reinforced concrete; Splicing; Strain (Mechanics); Strength of materials
• Old TRIS Terms: Strains
• Subject Areas: Bridges and other structures; Highways;

Filing Info

• Accession Number: 00209174
• Record Type: Publication
• Files: TRIS
• Created Date: Mar 30 1970 12:00AM