Concrete Bridge Assessment Program (COBRAS) is a yield-line analysis software program for assessing the ultimate load capacity of concrete structures, and in particular, concrete bridge decks.

A number of UK bridge authorities, consultants and overseas organisations are currently using the program to evaluate the load carrying capacity of concrete bridges that have failed assessment using conventional elastic analysis methods. The program has been developed in the Department of Engineering at the University of Cambridge by Dr Campbell Middleton and colleagues. The team have received support from various bodies including the Highways Agency, Transport Research Laboratory (TRL) and the Engineering and Physical Sciences Research Council (EPSRC).

A paper by Dr Campbell Middleton presented at the Surveyor Bridge Conference in London, March 1998 gives more information on the program and its use for concrete bridge assessment.

Further information can be found at the COBRAS website.

Licences to the software for both academic and commercial users are available for purchase by contacting us at the link below.