Investigate Causes & Develop Methods to Minimize Early-Age Deck Cracking on Michigan Bridge Decks

The research identified the major parameters influencing the concrete transverse deck cracking and made recommendations to modify these parameters in order to minimize deck cracking. The synthesis of the data collected revealed that the tensile stress due to early-age thermal load alone could cause deck cracking. Volume change of concrete due to temperature and shrinkage occurs simultaneously. An increase in drying shrinkage arising from delays in concrete placement and wet curing also affect the deck cracking. Additionally, drying shrinkage, beyond the very early ages, increases the crack widths that have previously formed due to thermal loads. Concrete parameters influencing the thermal load levels are: cement type, content, and fineness, ambient temperature at the time of concrete placement, and the time of inception of curing. An important recommendation of this study is the implementation of measures to control and manage thermal and shrinkage stresses in RC decks. The first conclusion is related to current practice. If the curing related stipulations of the Michigan Department of Transportation - Standard Specifications for Construction is strictly adhered to, the density of transverse deck cracks will be reduced. This research established that approximately a 20 degrees F of thermal load initiates deck cracking. Second, in order to reduce transverse cracking, the primary recommendation is to develop and optimize project specific mix design for the minimization of thermal load. Additional recommendations include the reduction and/or substitution of cement with mineral admixtures and use of current and forecast weather data in optimizing the mix design and placement time in order to minimize the thermal loads.

• Record URL:
  https://mdotjboss.state.mi.us/SpecProv/getDocumentById.htm?docGuid=290ac636-c299-4828-84de-8ac648063d04
• 
• Corporate Authors:

  Wayne State University

  College of Engineering
  Detroit, MI  United States  48202

  Michigan Department of Transportation

  Construction and Technology Division, P.O. Box 30049
  Lansing, MI  United States  48909
• Authors:
  • Aktan, Haluk M
  • Fu, Gongkang
  • Dekelbab, W
  • Attanayaka, Upul
• Publication Date: 2003-12

Language

• English

Media Info

• Media Type: Web
• Edition: Final Report
• Features: Appendices; Figures; Maps; Photos; Tables;
• Pagination: 364p

Subject/Index Terms

• TRT Terms: Bridge decks; Concrete curing; Mix design; Reinforced concrete; Shrinkage; Tensile strength; Transverse cracking
• Uncontrolled Terms: Early age (Concrete)
• Geographic Terms: Michigan
• Subject Areas: Bridges and other structures; Highways; I24: Design of Bridges and Retaining Walls;

Filing Info

• Accession Number: 01115309
• Record Type: Publication
• Report/Paper Numbers: Research Report RC-1437
• Contract Numbers: 2002-0223
• Files: TRIS, STATEDOT
• Created Date: Nov 25 2008 7:32AM