Development of a methodology for the optimized planning of retrofitting and/or replacement of important bridges

Many of the federal highways built before 1985 have a load-bearing capacity that is not sufficient to withstand the present or predicted freight traffic loads.

The project focused on the planning of necessary retrofitting and/or replacement measures for the bridges concerned. It built on the results of a completed previous project. In the project, a prototypical procedure for the calculation of optimized retrofitting programs has been developed, which minimize the macroeconomic impact of unavailability or limited usability of the bridges in a subnetwork.

The methodology was applied to selected Rhine crossings in North Rhine-Westphalia between Bonn and Duisburg.

In the project, the method was further developed with the aim of extending it to larger sub-networks. Furthermore, a software prototype for the calculation of optimized retrofitting programs was developed.

Method for the preselection of buildings

The procedure for the pre-selection of structures under constructional and macroeconomic aspects is intended to help building authorities to identify particularly critical structures at an early stage in order to include them in a procedure for planning measures at subnetwork level.

Methodology for the analysis of retrofitting options

With the new methodology the structural effects and the impacts on traffic and economy of different upgrading options can be assessed.

Methodology for setting up upgrading programmes for subnetworks

The upgrading programme is intended to generate the highest possible macroeconomic benefit for the selected subnetwork and to keep the user costs as low as possible.