An interpretation of the new guidelines multilevel approach for a railway bridge

In the last years for European governments, like in Italy, has become important to increase the attention on the maintenance plan activities and its assessment, analyzing their infrastructures as highway bridges or viaducts and focusing in particular on their structural elements as prestressed precast beams, piles, supports and slabs; This concern due to the fact that the percentage of failures and partial collapses are strictly connected with the age of the infrastructure, timing exposure and deterioration status. With this end, the Italian government has decided to apply a new procedure analysis, based on a multilevel approach composed by five different levels, directly connected between them in order to obtain an attention class index, starting to the project parameters knowledge until the monitoring phase characterized by using accelerometers or similar instruments, cabled directly on the bridges for real time recording. Moreover, in particular for the development of the level nr.2 that must describe the infrastructure status presently, an abacus with a large number of principal defects was developed for the common materials constituents like masonry, concrete, steel and wood to estimate the deterioration levels of each infrastructure elements. The objective of that work is the application of Italian guidelines on a railway bridge, in order to increase the knowledge on this kind of bridges and analyze if and how the multilevel approach allows to understand critical aspects of railway typologies structures or if particular suggestions are necessary.