Article
Investigate Causes and Develop Methods to Minimize Early-Age Deck Cracking on Michigan Bridge Decks
Michigan Department of Transportation
(2003)
Abstract
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. 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.
Keywords
- bridge deck,
- early-age concrete,
- reinforced concrete,
- shrinkage effect,
- thermal effect,
- transverse cracking
Disciplines
Publication Date
December, 2003
Citation Information
Haluk M Aktan, Gongkang Fu, Waseem Dekelbab and Upul Attanayake. "Investigate Causes and Develop Methods to Minimize Early-Age Deck Cracking on Michigan Bridge Decks" Michigan Department of Transportation (2003) Available at: http://works.bepress.com/upul-attanayake/66/