At the ACI spring convention in Milwaukee, I gave a presentation on the work we are doing in Delft with regard to load testing.
The abstract of the presentation is the following:
As the bridge stock in The Netherlands and Europe is ageing, various methods to analyze existing bridges are being studied. Load testing of bridges is an option to study the capacity when crucial information about the structure is lacking. This information could be related to the material (for example, the effect of ASR on the capacity) as well as to the structural system (for example, the effect of restraints at the supports or transverse redistribution capacity).
When it is decided to load test a bridge, the question arises which maximum load should be attained during the experiment to approve the capacity of the bridge, and which criteria, based on the measurements during the test, would indicate that the test needs to be aborted before reaching the maximum desired load (the “stop criteria”).
After proof loading and testing to failure of two spans of the Ruytenschildt bridge, beams sawn from another span were tested in a controlled way in the laboratory. The results of these beams have been analyzed with regard to the stop criteria as defined by the currently used codes and guidelines.
As a result of the analysis and experiments, recommendations are given for proof loading of bridges with respect to the stop criteria. These recommendations are important, since they will form the basis of a guideline for proof loading of existing concrete bridges that is under development in The Netherlands.
You can find the slides of the presentation here: