Modified wheel loads and design of anchorages for bridge deck joints

Anchorages of bridge expansion joints are subjected to severe and repeated dynamic loads from traffic and breakage of fasteners has been experienced on RTA bridges. Several design aspects of bridge deck joints are being reviewed by RTA and the design method currently adopted is summarised in this paper. The wheel patch in AS 5100.2 Bridge design Design loads is shown to be unsuitable for the design of deck joints and a patch with prescribed tyre inflation pressures and variable contact length for AS 5100.2 limit states is proposed. Formulas for calculating the stiffness of the bolt and bolted material are derived. Stresses in the bolt can therefore be calculated more accurately by considering interaction of the bolt with the bolted material. Safety of the joint due to sliding and overturning is checked. The torque and rotation required to impart the required preload can be calculated. As preload cannot be accurately predicted with common methods of bolt tensioning, it is proposed to design the bolt for a range of preloads. The appropriate preload is chosen for checking safety under different limit states. (a) For the covering entry of this conference, please see IRRD abstract no. E218160.

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  • English

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Filing Info

  • Accession Number: 01143970
  • Record Type: Publication
  • Source Agency: TRL
  • Files: ITRD, ATRI
  • Created Date: Nov 16 2009 12:17PM