Assessment and Re-Analysis of Existing RC / PC Bridges in Germany. General Aspects and Exemplary Presentation of an Incrementally Launched 2 x 3 Lane Autobahn bridge Across the Danube

Abstract

In May 2011 the new guideline “Nachrechnungsrichtlinie” (NaRil; standard for bridge re-analysis and assessment) was recommended for application by the Federal Ministry of Transport, Building and Urban Development [1]. Since then several pilot projects have been launched in Bavaria aiming on the re-analysis of different types of major road bridges based on the assessment guideline. One of these bridges is the BAB A9 Danube PC box-gir-der bridge next to Ingolstadt. Upon completion of the re-analyses according to the so-called levels 1 and 2 of the guideline there were still severe calculatory deficits particularly regarding the connection zones of the compression flanges and webs close to the supports. By using a 3D FE model and physically non-linear analysis methods combined with in-situ investigations (i.e. level 4 of the guideline) it was finally possible to fulfill all design criteria and hence to avoid both traffic restrictions as well as strengthening measures. The present paper describes the general assessment approach and highlights important findings and results of the non-linear analyses. Finally, the Danube Bridge results are discussed with the background of a current research project focusing on a systematic evaluation of available re-analyses of RC/PC bridges performed on the basis of the new assessment guideline.