01340576

Component

The authors’ survey of state bridge engineers indicates that 17 of 50 states use the American Association of State and Highway and Transportation Officials (AASHTO) empirical method to design concrete bridge decks. To better understand advantages and disadvantage of the empirical method, the authors investigated the ability of the empirical deck design method to control deck cracking and compare it to AASHTO’s traditional deck design method. The authors reviewed the literature regarding the effect of bridge deck design methodology on deck cracking and found that some researchers suggest that the empirical bridge deck design method should be modified to limit cracking. Some indicate that the empirical method should require an increased reinforcement ratio to adequately control cracking. Others believe that the deck-to-girder stiffness has a greater effect on deck cracking and should be increased in the empirical method. The authors also surveyed bridge deck design methods and typical deck designs for all of the states in the U.S. Bridge deck properties such as deck thickness, rebar size and rebar spacing from other states were compared. Reinforcement bar size and spacing and deck thickness for typical designs vary considerably from state to state. The consensus among states indicates that reducing the spacing and increasing the size of rebar would mitigates deck cracking problems, although the degree to which deck crack spacing and width would be mitigated would require further research.

01329018

11-2979

English

15p

2011

Transportation Research Board 90th Annual Meeting

DVD

Figures (6) ; References (24) ; Tables (2)

Bridge decks; Bridge design; Concrete bridges; Cracking; Empirical methods; Girders; Reinforcing bars; Stiffness; Thickness

American Association of State Highway and Transportation Officials

Bridges and other structures; Highways; I24: Design of Bridges and Retaining Walls

Transportation Research Board Annual Meeting 2011 Paper #11-2979

TRIS, TRB

Feb 17 2011 6:21PM