Bridges

Cover of Experimental investigation of the effective width of composite bridges with dry joints
Experimental investigation of the effective width of composite bridges with dry joints
  • Publication no: ABC-IAR003-11
  • Published: 31 October 2011

This paper deals with an experimental investigation of a new type of composite bridge using fully prefabricated concrete elements, which shortens the construction time and hence reduces production and economic costs.

Up to now, composite bridges have reached a high level of prefabrication. Nevertheless, typical advantages of prefabrication, like fast erection times and high manufacturing quality, are partially compensated during the on-site assembling process when the elements are connected among themselves with an infill concrete.

The aim of this study is to investigate the effect of ‘dry joints’, i.e. joints leaving a gap between the precast elements which is not filled with concrete, on the load bearing behavior of such composite bridges. To address this problem, six large scale tests on composite girders using prefabricated elements and dry joints were carried out. The concrete strains were measured along numerous cross sections to define the load bearing part of the concrete elements in terms of effective widths. It could be shown that the use of dry joints reduces the effective width and impairs the deformation behavior, whereas no major influence on the results could be observed by varying the size of the gap between the elements. The ultimate bearing capacity was affected only slightly as well. Accordingly, composite bridges with dry joints open up the possibility to reduce construction time significantly and are an attractive alternative to current types of bridge design in cases where closing times of traffic routes are to be minimized.