Abstract
Differential displacements are commonly induced between precast reinforced concrete members during construction such as in connections on staged bridge construction projects. The ultimate bond strength between reinforcing bars (rebar) and an embedment material used in the connections may be affected. A pullout test was devised to compare the early age ultimate bond strength developed in specimens with and without differential displacements. A range of different grout and concrete materials (embedment materials) used within typical connections were tested. Maximum relative displacements at right angles to #13M (13 mm diameter) rebar ranged from 2.5 to 0.13 mm (a bar diameter–displacement ratio ranging from 10 to 200). These displacements were imparted from casting until the embedment materials reached final set. Pullout testing on both static and displaced test specimens was subsequently performed at approximately 24 h after casting. When the rebar displaced 1.3 mm or more (a bar diameter–displacement ratio of 20 or less), reduced bond capacity was observed in all embedment materials tested. When the rebar displaced 0.25 mm or less (a bar diameter–displacement ratio of 100 or more), the results indicate insignificant variations in bond strength regardless of embedment material type. These results show that large displacements applied prior to final set of the embedment material can have a detrimental effect on the pure bond strength.
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References
American Association of State Highway and Transportation Officials (2010) AASHTO LRFD Bridge Design Specifications. American Association of State Highway and Transportation Officials, Washington, DC
American Concrete Institute (ACI) (2005) Manual of concrete practice, vol 3. American Concrete Institute (ACI), Detroit
American Concrete Institute (ACI) Committee 408: ACI408R-03 (2003) Bond and development of straight reinforcing bars in tension. American Concrete Institute, Farmington Hills
Arnold DJ (1980) Concrete bridge decks: does structural vibration plus excess water form the fracture plane. Michigan Department of Transportation
ASTM International (1991) Standard test method for comparing concretes on the basis of the bond developed with reinforcing steel. ASTM C 234. ASTM International, West Conshohocken
British Standard 4449 steel bars for the reinforcement of concrete (1978). British Standards Institution, London
Cairns J, Abdullah R (1995) An evaluation of bond pullout tests and their relevance to structural performance. Struct Eng 73(11):179–185
Cohen J (1988) Statistical power analysis for the behavioral sciences. Lawrence Erlbaum Associates, Hillsdale
Csagoly PF, Campbell TI, Agarwal AC (1972) Bridge vibration study downsview. Ontario Ministry of Transportation and Communications
Devore JL (1995) Probability and statistics for engineering and the sciences. Wadsworth Publishing Co., Belmont
Faul F, Erdfelder E, Buchner A, Lang AG (2009) Statistical power analyses using G*Power 3.1: tests for correlation and regression analyses. Behav Res Methods 41:1149–1160
Feldman LR, Bartlett FM (2005) Bond strength variability in pullout specimens with plain reinforcement. ACI Struct J 102(6):860–867
Furr HL, Fouad HF (1981) Bridge slab concrete placed adjacent to moving live loads. Texas Transportation Institute
Graybeal B (2012) Influence of differential deflection on staged construction deck-level connections—TechBrief. Publication No.: FHWA-HRT-12-055. U.S. Department of Transportation, Federal Highway Administration, McLean
Hao Q, Wang Y, He Z, Ou J (2009) Bond strength of glass fiber reinforced polymer ribbed rebars in normal strength concrete. Constr Build Mater 23(2):865–871
Harsh S, Darwin D (1983) Effects of innovative construction procedures on concrete bridge decks, final report Part II, effects of traffic induced vibrations on bridge deck repairs. University of Kansas Center for Research
Harsh S, Darwin D (1984) Effects of traffic induced vibrations on bridge deck repairs. University of Kansas Center for Research
Issa MA (1999) Investigation of cracking in concrete bridge decks at early age. J Bridge Eng 4(2):116–124
Kwan AK, Ng PL (2006) Reducing damage to concrete stitches in bridge decks. Bridge Eng 159(2):53–62
Larnach WJ (1952) Change in bond strength caused by re-vibration of concrete and the vibration of reinforcement. Mag Concr Res 4:17–21
Manning DG (1981) Effects of traffic-induced vibrations on bridge-deck repairs. NCHRP Synthesis 86
McMahon JE, Womack JC (1965) Bridge widening problems. California Division of Highways
Montero AC (1980) Effect of maintaining traffic during widening of bridge decks (a case study). Ohio State University, Columbus
Prenger HB (1992) Bridge deck cracking. Maryland Department of Transportation
RILEM/CEB/FIP (1978) Bond test for reinforcing steel 2: pullout test. Recommendation RC6. RILEM/CEB/FIP, Bagneux
Swenty MK, Graybeal BA (2012) Influence of differential deflection on staged construction deck-level connections. Report No.: FHWA-HRT-12-057. Office of Infrastructure Research and Development, Federal Highway Administration, McLean
Whiffen AC, Leonard DR (1971) A survey of traffic induced vibrations. Transport and Road Research Laboratory, Wokingham, Berks
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The publication of this paper does not necessarily indicate approval or endorsement of the findings, opinions, conclusions, or recommendations either inferred or specifically expressed herein by FHWA or the US Government. The research discussed herein was completed at the Turner-Fairbank Highway Research Center. Portions of the work were completed by PSI, Inc., under contract DTFH61-10-D-00017. Matthew Swenty, formerly employed by PSI, Inc., and currently employed by the Virginia Military Institute, was the Co-principal Investigator on this project with Benjamin Graybeal who leads the FHWA Structural Concrete Research Program.
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Swenty, M.K., Graybeal, B.A. Effects of early age differential displacements on concrete–bar bond in the connections of staged constructions. Mater Struct 48, 3129–3140 (2015). https://doi.org/10.1617/s11527-014-0386-4
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DOI: https://doi.org/10.1617/s11527-014-0386-4