SAMCO Final Report 2006 F09 Report on Bridge Management
THE EUROPEAN BRIDGES
The bridges are key elements in the infrastructure, since they represent 30 % of the infrastructure investments and are the critical parts of the infrastructure in terms of safety and functionality for the whole infrastructure.
The ageing and deterioration of the bridges and the increased traffic intensities and loads, makes the bridges the bottlenecks of the transport infrastructure. The incon- veniences (congestions) created by the necessary activities for upgrading and repair- ing the bridges grow rapidly with increased traffic and age.
3.1 The age of the bridges
In the second half of the past century, the road network throughout the world was developed/expanded and the number of bridges increased correspondingly. This growth has reached its peak around the ‘70s in many countries, but there is still a limited request of new constructions although the maintenance costs for the more mature bridges (especially if built in the 50s and ‘60s) grow with an increasing speed.
Distribution of bridges
40 30 20
<1900 1901-29 1930-49 1950-59 1960-69 1970-79 1980-89
Former West Germany
Fig. 8. Distribution of the age of road bridges /OECD, 1992/, /Di Mascio et al, 1998/. Note (1) indicates that data are only for the bridges under Autostrade.
In general the limited availability of economic resources has made necessary a care- ful analysis of the conditions of the existing bridges with the aim of foreseeing and planning the interventions of repair not only for the existing population, but also for the bridges to be built by formulating new methodologies of design, able to optimize the type of structure and the choice of materials to minimize the totals cost of the structure (construction + maintenance)
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